Hz Mixer

Local session
Settings stay on this device

Ready
30:00

Monitor

RMS-- dBFS
Ready

Generator

Generator mode
Frequency program
Hz
0.1120 Hz
Hz
15000 Hz
Left 196.000 Hz · Right 204.000 Hz
Stereo headphones

Environment

0 layers

Noise

Bells

Independent audio layers
Hz MixerMixer

Hz Mixer Guide

Hz Mixer combines binaural beats, monaural beats or isochronic pulses with field recordings and generated noise. This guide covers the mixer, frequency programs, saved mixes, audio export and offline use.

Listening Safety

Use Hz Mixer only while sitting or lying down in a safe place. Do not use it while driving, operating machinery, or where reduced alertness or altered awareness could cause injury.

Start with low device and mixer volumes, then adjust to a comfortable level. Pause and remove your headphones if the sound is uncomfortable or you feel unwell. Do not raise the volume just because a very low carrier is difficult to hear.

Hearing risk depends on sound level, listening duration and repeated exposure. The Monitor measures digital audio in dBFS, not sound pressure at your ears. A mixer percentage or meter reading cannot establish a safe headphone volume. For general hearing guidance, see the World Health Organization's safe-listening advice.

Use stereo headphones for binaural playback. Monaural, isochronic and environment-only mixes do not require separate signals at each ear.

Quick Start

  1. Sit or lie down, lower your device volume, and connect stereo headphones if using binaural mode.
  2. Choose a preset from Mix library, or set a generator mode, beat rate and carrier pitch.
  3. Enable the environment tracks or noise you want and set their levels.
  4. Select a session timer or No timer, then press Play. Hz Mixer never starts restored audio automatically.
  5. Adjust Tone level, individual layer levels and Master gradually. Pause preserves progress; Stop returns the program to its beginning.

The information button in the header opens a short reference and the full guide. The guide opens inside the current mixer without changing playback or settings; select Mixer to return. The website also provides a dedicated guide.html page for direct links.

Reset mixer is the larger circular-arrow button in the playback controls. It restores a tone-only default with every recording, noise channel and bell off, without deleting saved mixes or changing interface/theme preferences. Fresh sessions use the same default; restored and imported mixes retain their saved channel selections.

Generator Modes

Mode Signal Listening setup
Binaural One tone at carrier minus half the beat rate in the left channel, and one at carrier plus half the beat rate in the right. Stereo headphones.
Monaural Those two tones mixed into both channels. Headphones or speakers.
Isochronic One carrier whose amplitude repeats at the beat rate. Headphones or speakers.
Off No generator tone; enabled recordings and noise remain available. Headphones or speakers.

For example, a 200 Hz carrier and 8 Hz binaural beat use 196 Hz on the left and 204 Hz on the right. Monaural mode mixes those frequencies together; isochronic mode pulses a 200 Hz carrier eight times per second.

Generator mute silences only the tone. Generator solo isolates it from other enabled layers, unless another layer is also soloed. Turning the generator Off clears its solo state.

Frequencies and Presets

Type a value directly or use its slider:

  • Beat rate: 0.10-120.00 Hz, in 0.01 Hz steps.
  • Carrier pitch: 1-5000 Hz, in whole-hertz steps.
  • Tone level: generator level, independent of the environment and Master.

The two-tone modes require carrier pitch to be greater than half the highest beat rate in the program. Invalid combinations show an error because the lower tone would reach zero or a negative frequency. For sweeps and sessions, this check covers their rates too.

The carrier range includes infrasonic frequencies below 20 Hz; a generated signal is not a guarantee that the playback system reproduces its fundamental. Modulation can introduce audible higher-frequency components. The selectable range describes signal settings, not whether a binaural beat will be perceptible at every combination. High pulse rates can sound like a buzz or rough texture instead of separate pulses.

Live playback checks the audio context's sample rate against the generator's frequency budget. If a device uses a lower sample rate that cannot accommodate the settings, the generator shows an error rather than silently changing the frequencies. WAV and MP3 exports use their selected 44.1 or 48 kHz rate.

The library has 61 presets, grouped by band. Search matches names, bands, enabled methods, programs and active sound layers, including saved mixes. Multiple words (such as theta isochronic sweep) and Favorites narrow the results. The band ranges are:

Band Range
Delta 0.10 Hz to below 4 Hz
Theta 4 Hz to below 8 Hz
Alpha 8 Hz to below 13 Hz
Beta 13 Hz to below 30 Hz
Gamma 30-120 Hz

Environment-only presets appear under Environment only. Selecting a preset loads its generator, program, layer and level settings and resets the frequency-program clock. It does not start playback. Editing settings makes the selection Custom; saving creates your own named mix. Reset restores the starting mix without deleting your library.

The readout lists enabled tones, methods and fixed/sweep/Session rates. Independent programs show separate rates. Muted or solo-excluded tones remain in this configuration summary.

The dice button beside Reset generates a new random mix rather than selecting a random preset. It varies the generator method, rates, carrier, pulse shape and a limited selection of environment, noise and bowl layers. Master level, master mute, fades, timer and the current Fixed/Sweep/Session selection are retained. Sweep timing and repeat behavior, or session stage types, durations and transitions, are also retained while their rates change. Session parameter changes are cleared. Applying a roll restarts the program clock but does not start stopped or paused playback, change your theme, or alter saved mixes and favorites. Save mix keeps a roll you like.

The permanent Restore previous mix arrow beside Dice restores the settings from immediately before the last Reset or Dice action. It is disabled until one of those actions creates a restore point. Another Reset or Dice replaces that point; editing or loading a mix, restoring it, or reloading the page clears it. This is one-step restoration, not redo or audio rewind. Playback remains playing or paused, with the restored program clock starting at zero. Saved mixes and favorites are not changed. A previously selected preset or saved mix is reselected only if that entry still matches the restored settings; otherwise the restored mix is Custom.

Simple mode generates a single tone layer without source effects. Advanced mode can add up to two following tone layers, waveform changes, AM, slow panning, gentle pitch modulation and filtering. Randomization uses moderate channel levels and checks the known audio sample-rate budget; it does not randomly raise the master or remove a master mute. The existing playback and export validation still applies.

The library includes fixed-rate mixes, five sweeps and three staged sessions. A moving program is grouped by its starting beat rate, even if it later crosses into another band. Examples include:

Preset Mix
Three carriers / 7.83 Hz Three binaural pairs at 174, 348 and 522 Hz, with light pitch modulation, pink noise and surf.
Binaural + AM / 10 Hz A binaural pair with sine-wave amplitude modulation over sea waves.
Pink AM / 40 Hz Monaural tones and pink noise with opposite-phase left/right amplitude modulation.
Rain dual sweep / 7.83 to 4.5 Hz Binaural and isochronic tones follow the same 15-minute sweep in each direction, over window rain and pink noise.
Current dual sweep / 22 to 14 Hz Binaural and isochronic tones descend together over ten minutes, then hold for the rest of the 20-minute session.
Current to embers / 18 to 6 Hz A 20-minute staged program that crossfades a stream into a campfire as the rate descends.
Stream & Singing Bowl I Environment-only stream with a bowl every three minutes.
Filtered white drift Environment-only low-pass-filtered white noise with slow stereo movement.

Simple mode plays the complete preset; an Advanced settings in mix indicator appears when it includes extra tones, effects or parameter changes. Switch to Advanced to edit those settings. Selecting a preset does not change your interface mode.

Isochronic Pulse Shape

Pulse controls appear only in Isochronic mode:

  • Width, 10-90%: the portion of each beat cycle occupied by the pulse, including its softened edges. A wider pulse lasts longer; a narrower one is shorter. The beat rate itself stays unchanged.
  • Softness, 0-100%: the amount of smoothing at the start and end of each pulse. Higher values use longer, gentler transitions. Low values make the pulse more abrupt.
  • Depth, 0-100%: how far the amplitude falls between pulses. At 100%, the intended envelope falls to silence; at 0%, the carrier is continuous. Intermediate depths keep a background level of the carrier.

Pulse shape changes both timbre and average signal energy. At the same Tone level and full depth, wider pulses carry more average energy than narrower pulses. Width is not automatically loudness-normalized. Lower the tone first when experimenting with a wider or more abrupt pulse.

Pulse shaping applies only to the generator. Recordings and noise have independent level controls.

Frequency Programs

Fixed holds the manual beat rate. The Beat rate number and slider appear only in Fixed. Sweep and Session use their own rate controls, while Carrier pitch remains available in every program. Returning to Fixed restores its last manual rate.

Sweep moves between Start Hz and End Hz over 5-7200 seconds. Linear changes at a constant rate; Smooth eases the transition at the ends. Once, then hold keeps the end rate after the sweep finishes. Ping-pong alternates forward and return sweeps. The selected session timer still determines when playback ends; No timer permits continuing playback.

Session opens the stage editor inside Generator, beside the environmental mixer rather than beneath all its tracks. A Hold shows one Rate Hz. A Sweep shows Start Hz, End Hz and a Linear or Smooth transition. Enter each duration as minutes and seconds. Add, remove or move stages with the stage buttons. A session contains 1-16 stages, each 5 seconds to 60 minutes, with a combined maximum of two hours. Its timer comes from the stage total and cannot be selected separately.

The program monitor shows the rate path, current position and current stage. Editing sweep settings, editing/reordering stages or changing program type resets the program clock. Ordinary level, mute and balance changes do not reset it. Pause preserves the current clock position.

Playback and Fades

Play starts a stopped mix, or resumes a paused one. Pause holds the program position and suspends playback. Selecting a different mix resets its frequency-program clock.

Stop uses the selected fade-out and resets the position. Press Stop again during that fade to end immediately. A finite timer stops automatically at its endpoint. No timer keeps playback running until you stop it.

Fade in and Fade out accept 0-30 seconds. They apply to the whole mix. For short timed sessions, fades are limited to fit within half the session length. A zero-second fade-out holds the level until the endpoint instead of gradually fading across the session.

Master changes the whole mix; Master mute silences all channels without changing their individual levels. Output processing includes a shared compressor to manage peaks, so very loud combined layers can change the mix's dynamics. Neither the compressor nor Master measures the listening volume produced by your headphones or speakers.

Environment and Noise

The environmental recordings are Waterfall, Stream, Thunderstorm, Sea waves, Campfire and Window rain. Waterfall is mono; the others are stereo. Window rain is rain against glass, separate from the rain-and-thunder recording. The displayed duration is the source recording length, rounded to seconds. Playback uses a derived, crossfaded loop, so the repeat interval is slightly shorter. The four original MP3 recordings are unchanged; Campfire and Window rain are converted from source WAV files.

White, pink and brown noise are generated locally. White has a broad spectrum; pink and brown place progressively more emphasis on lower frequencies. They use the same channel controls as recordings.

Each layer has:

  • Enable: include or remove the channel.
  • Level: adjust its contribution to the mix.
  • Mute: silence it without changing its level or enable state.
  • Solo: hear only enabled, soloed channels. Selecting Solo also enables that channel.
  • Balance: move its signal left or right. Select the balance readout to reset it to Center.

Every level slider has a percentage box. Type 0-100, then press Enter or leave the field to apply. Invalid or empty entries revert; Escape discards an edit. Main/master and environment levels use whole percentages; extra tones can retain fractions. Editing does not enable, unmute or solo a source.

Mute wins over solo. Disabling a channel clears its solo flag. Clear solo removes all solo flags while leaving enabled layers on. A Loading state means the recording is being fetched or decoded; Unavailable indicates a load failure. Website recordings are loaded only when needed. The portable HTML already contains them.

Interval Bells

Singing Bowl I and Singing Bowl II are two Tibetan bowl recordings. Each is off by default and has its own level, mute, solo, balance and Repeat every field in minutes. Enter 1 for every minute, 5 for every five minutes, or another interval from 0.25 to 120 minutes. The adjacent arrows, or the Up and Down keys while editing the field, adjust the interval by 15 seconds. For example, 0.75, 0.5 and 0.25 minutes are 45, 30 and 15 seconds. Typed intervals are stored to the nearest second.

An enabled bell strikes at the beginning of the session and at each interval multiple. It plays its recorded decay once, followed by silence, rather than looping the bell continuously. There is no automatic final bell. Normal master level, mute, session fades and timer apply, so a session's fade-in can soften the initial strike and its end can cut off a decay.

On initial loading, the first strike starts from the beginning of its recording as soon as it is available; later strikes retain their session-clock positions. If loading takes an entire interval, missed strikes are skipped instead of replayed in a burst.

The interval follows elapsed session time, not wall-clock time. Pause freezes that clock; Resume continues the current decay or the remaining interval without an extra strike. Stop resets the clock. Applying a preset or saved mix also restarts the program clock. Enabling a bell or changing its interval during playback aligns it to the current session clock, including any decay already in progress. Hidden-tab delays do not create a burst of missed strikes.

Bells remain independent of the generator's beat rate and pulse envelope. They use the same mute/solo rules as environment and noise channels. Saved mixes and JSON backups retain both intervals, and WAV/MP3 exports include the same scheduled strikes, with no extra strike exactly at the export endpoint. The lossless PCM WAV files preserve the supplied AIFF samples without crossfading or resampling the source files.

Monitor

The Monitor above Generator displays the combined output as a waveform or a spectrum. Select the view using its two buttons. The RMS readout and bar show a digital signal level in dBFS; they are not a calibrated measurement of headphone volume.

The session clock shows the time remaining, or a placeholder when no timer is selected. The generator readout shows the two intended tone frequencies or the current isochronic pulse rate. For active programs, the rate changes as the program advances.

Saved Mixes and Favorites

Save mix stores a named snapshot in this browser. Up to 30 named mixes are supported, with names up to 40 characters. Saving an existing name updates that entry; the dialog tells you when this will happen. Built-in presets are not overwritten.

Choose a saved entry from Mix library to load it. Delete removes the selected saved entry but retains the settings currently in the mixer. Favorites apply to built-in presets and are included in library backups.

Current settings, saved mixes, favorites, theme and Matrix pause state use local browser storage. Private browsing, clearing site data, changing browsers or moving the portable file can affect what is available. A saved mix in one browser or file location is not automatically shared with another.

Import and Backup

Export has separate Mix JSON and Library backup tabs. Mix JSON contains the current mix and program settings. Library backup includes named mixes, the current mix and built-in preset favorites. Neither includes theme or Matrix motion preferences.

To transfer your library, export a backup from the old location, then import it in the new one. Audio exports cannot restore editable mixer settings; use JSON for that.

Import accepts version 2-6 Hz Mixer JSON files smaller than 4 MB. It validates and previews entries before making changes. Merge keeps existing saved mixes and adds imported entries; Replace replaces the saved library with the previewed entries. Conflicting names receive an import suffix instead of silently overwriting an unrelated entry.

Exports that contain beat rates outside 0.50-40.00 Hz or carriers outside 20-2000 Hz use version 3, including expanded values in inactive sweeps/stages. Older builds reject these files instead of silently clamping their frequencies. Mixes that fit the older limits still export as version 2.

Mixes with non-default Campfire or bell settings use version 4 instead, including changed settings on disabled channels. Older builds reject version 4 rather than silently discarding those layers. Versions 2 and 3 import with the new channels off by default.

Non-default Window rain settings use version 5, including changed settings while the channel is disabled. This prevents older builds from dropping the channel silently. Version 2-4 files import with Window rain off by default.

Non-default effects, tone-layer settings or stage parameter changes use version 6, including configured but disabled effects and tone layers. Version 2-5 files restore with effects off, the original sine carrier and no additional tones. Unchanged mixes keep the previous export-version rules.

The preview shows the resulting count against the 30-mix limit. A library backup's current mix can optionally become a saved entry. That option is initially unchecked if including it would exceed capacity while the saved library itself fits. An overflowing or invalid import cannot be applied.

Import does not start playback or load the imported settings into the current audio automatically. Select the imported entry from Mix library afterward. If a replaced entry no longer matches the current settings, the current selection becomes Custom rather than silently changing the sound.

Audio Export

Choose Export, then Audio, and select a format:

Setting Options
WAV Stereo 16-bit PCM, uncompressed
MP3 Stereo, lossy, 128/192/256/320 kbps; default 256 kbps
Sample rate 44.1 or 48 kHz
Duration 1 second to two hours

Exports render a snapshot of the current settings from the beginning of the program, not a recording of past live edits or the current playhead. Live changes after export starts do not alter that snapshot. The render includes mute/solo, balance, levels, pulse shape, sweeps/stages, fades and output processing.

Session exports use the stage total. Other programs let you edit export duration. The suggested length follows the current program or timer; a one-way sweep initially suggests its sweep duration. Export rejects a silent mix or invalid two-tone frequency combination.

WAV is the uncompressed reference and has an exact PCM sample count. MP3 is smaller but adds codec delay/padding, so decoded duration can be slightly longer. Both preserve left/right channels. Converting a binaural export to mono elsewhere removes its separate-ear routing.

Generator exports use a short matching-time overlap at render-block boundaries to smooth small native oscillator restart differences. This does not add or remove samples or change the pulse-shape settings.

The progress indicator shows loading, rendering and encoding. Cancel detaches from pending recording or encoder downloads without cancelling a load shared with playback. An already-running native render finishes its current block; MP3 encoding yields between smaller batches. Shared downloads may finish for cache reuse.

Ordinary downloads keep encoded chunks in browser memory. Long exports can still use substantial memory. Save directly to file appears only where the browser supports that API and uses its native file picker. Before finalization, a cancelled direct writer is aborted instead of committed. Once writing is complete, Finalizing commits the file; Cancel is disabled and Escape does not dismiss the dialog until this finishes. A commit error is shown in the dialog and the controls become available again. Inspect the destination if a browser or operating system reports an error.

The MP3 encoder loads only when needed on the website. It is embedded in the portable HTML. An audio export is not a JSON settings backup.

Mixer Workspace

Simple is the default interface. It keeps Generator and all Environment tracks together below the Monitor, side by side on desktop and stacked on smaller screens. Fades remain in Generator. Choosing Session as the frequency program shows its stage editor inline in Generator.

Advanced keeps that same arrangement and reveals additional tone layers, carrier shaping, source effects and stage parameter changes. The Simple/Advanced selection is remembered on this browser, separately from saved mixes. Switching interfaces does not change the sound, clear hidden settings, reset playback or alter exports. Simple displays Advanced settings in mix when a mix contains extended settings.

Tone Layers

Advanced adds Tone 1, Tone 2 and Tone 3 tabs to Generator. Tone 1 has the original Generator controls, carrier bookmarks, waveform and balance. Tone 2 and Tone 3 each have an enable switch, method, program, carrier, beat rate, waveform, level, mute, solo and balance. Additional tones and effects are off by default. Solo and Clear solo operate across all tones, environment, noise and bells. Settings are included in saved mixes, JSON backups and audio exports unless explicitly described as monitor-only.

Follow Tone 1 uses the main frequency program. Fixed shows the selected tone's own Beat Hz. Sweep uses its own start/end rates, duration, curve and Hold end or Ping-pong repeat behavior. The manual Beat Hz field is hidden for Follow and Sweep. All tones use the same transport clock and overall session timer; Pause/Resume preserves progress and Stop resets it.

Carrier bookmarks include 174, 200, 250, 285, 300, 396, 400, 417, 432, 528, 639, 741, 852 and 963 Hz. These select a numeric carrier; they do not retune recordings. In binaural/monaural methods, carrier remains the center of the two component frequencies.

Sine uses the original carrier. Triangle, Square and Sawtooth are finite-harmonic versions with up to eight partials. Harmonic blend exposes H2/H3/H4 amplitudes relative to a fixed fundamental. Combined absolute partial amplitudes are normalized for headroom. Waveforms and modulation settings must fit the actual audio sample rate; invalid combinations show an error rather than silently changing the controls.

Generator trim is 1/N for N enabled tones included by mute/solo. Its decibel value appears as Tone headroom next to the tone tabs. Enabled zero-level tones still count, keeping trim stable during crossfades. Environmental/noise/bell levels are not included in that trim.

Effects

In Advanced, the sliders icon beside each tone, recording or noise source opens its effects popup. The button is highlighted when that source has effects enabled. Effects for can switch directly to another source. Each retains its own settings, grouped into AM, Movement, Pitch and Filter. The reset button resets only that source's effects, not its level, waveform or program. Close or Escape returns to the source button. Bells keep their independent interval playback and are not included in the effects selector.

Amplitude modulation uses a nonnegative volume envelope. Depth is the dip from the unmodulated peak: 0% leaves amplitude unchanged and 100% applies the full envelope. Shape selects Sine, Triangle, Square or Rounded pulse. Width changes square/pulse duty cycle; Softness controls rounded-pulse edges. Sharp shapes use a 64-harmonic smoothed reconstruction, so their transitions are band-limited rather than mathematically instantaneous.

Timing can follow the source's beat program or use an independent 0.10-120.00 Hz rate. Generator sources follow their own Follow/Fixed/Sweep selection; recordings and noise follow the main program. Phase is in degrees. Linked channels use the same envelope. Phase offset adds Right phase to the right channel. Independent channels also use Right rate; the left channel can still follow its selected timing. Mono noise/recordings are duplicated to stereo before separate envelopes are applied.

Combining a binaural generator with AM keeps the carrier tones in separate ears. Square or Rounded pulse provides a binaural-plus-pulse combination. Isochronic mode retains its original Width/Softness/Depth shaping; its optional AM block adds another envelope after that shaping.

Auto pan / balance has a rate, depth and phase. Environmental/noise sources use stereo panning. Generated sources use separate left/right gains without crossfeeding the carrier channels. Static and automated balance remain available; movement is clamped at the channel extremes.

Pitch modulation is available on generators. FM uses deviation in Hz; PM uses phase depth in degrees. Both have their own rate and are applied equally to both carrier channels, preserving their fundamental frequency difference. FM/PM depth, carrier harmonics and amplitude modulation contribute to the frequency-budget check.

Filter selects Off, Low-pass, High-pass, Band-pass or Notch, with Frequency Hz and the native Web Audio Q parameter. Filtering occurs before AM and is a general sound-shaping control. Filters retain stereo channels. Resonant settings can increase peaks; layer and Master controls still determine the mix level.

The AM envelope preview shows the selected source's current shape/depth and channel relationship over two left-channel cycles. Monitor A/B switches between processed AM and dry amplitude for listening only. Match level attenuates the dry signal using the envelope's RMS factor; it is disabled when depth is automated. Closing the popup, switching source or leaving AM ends the dry audition. A/B never changes saved settings or exports: audio exports always use the configured processed mix, even while B: Dry is selected.

Session Changes

Choosing Session in Generator's frequency program activates its inline stage editor. Hold stages show a single rate and duration; Sweep stages also show an end rate and transition. Duration has separate minutes and seconds inputs. In Advanced, the editor stays in the Generator area when switching tone tabs. Fade-in/out remain in Generator.

In Advanced, expand Parameter changes on a stage to reveal Add change and its configured changes. The count remains visible while collapsed; collapsing does not disable or remove anything. Choose a Setting, enter From and To values, then select a Linear or Smooth transition. Each stage supports up to 16 unique settings: source Level, Balance, AM depth, Filter Hz and tone Carrier Hz. Bell levels are available, but strike intervals remain independent.

For a layer crossfade, enable both sources and add opposing Level changes in the same stage, for example one from 40 to 0 and the other from 0 to 40. A source or effect must be enabled separately: a stage change does not enable a disabled channel, AM block or filter. Changes configured while session stages are off remain inactive.

Parameters hold their last endpoint until another stage changes them. Transitions between different stage endpoints include a 20 ms dezipper. Source levels, carrier phase, modulation phase and filter scheduling use the same timeline in live playback and chunked exports. Editing active stages or their changes resets the session clock. Moving/removing a stage moves/removes its changes with it.

Themes and Motion

The header offers System, Dark, Light, Green, Blue and Matrix. Green is the original dark-green palette. Dark uses near-black with purple accents; Blue uses cyan/yellow/magenta accents. Matrix uses a black/green palette and falling background code, mixing kanji, katakana, letters/numbers and vertical mixer vocabulary such as BINAURAL, BEAT and MIXER. Monitor colors follow the selected theme.

System follows the device's light/dark preference.

Matrix has its own pause/resume button. Reduced-motion preferences disable the rain, and hidden tabs or other themes stop its animation. This preference is separate from mix backups. The rain is decorative and is not synchronized to the beat.

Privacy and Offline Use

Generation, mixing, audio export, encoding and JSON import happen in the browser. Hz Mixer has no account system, analytics, microphone capture or upload endpoint. It does not upload your settings, imported JSON or exported audio.

The website requests static app files, enabled recordings and the MP3 encoder from its host. Hosting still receives those normal requests; GitHub Pages records visitor IP addresses for security. There is no service worker or automatic offline installation.

The portable Hz Mixer.html embeds the application, recordings, icons, guide, encoder, notices and corresponding encoder source. It needs no companion files or local server and makes no automatic runtime network requests. Links to outside websites open only when selected. Play is still required before audio starts.

Website and portable-file storage are separate. Moving or renaming a portable file may also create separate storage. Export a Library backup before changing locations, and import it afterward. Browser/operating-system background and lock-screen behavior varies; verify listening on the device you intend to use.

Troubleshooting

  • No sound: press Play, check device output and volume, then inspect Master mute, generator/layer mute, enable switches and solo flags. In Off mode, at least one environment/noise channel must be enabled and raised.
  • Only one part of the mix is audible: check Solo first. Clear solo restores all otherwise-enabled, unmuted layers.
  • Two-tone error: raise carrier pitch above half the program's highest beat rate or lower that rate.
  • A pulse sounds too abrupt or dominates the recording: lower Tone level, increase Softness, or reduce Depth. Width also changes average tone energy. Adjust one control at a time.
  • Recording unavailable on the website: check the connection, then disable/re-enable that channel to retry. The portable build includes recordings locally.
  • Saved mixes appear missing: return to the same browser and website/file location, or import a previously exported Library backup.
  • Import is disabled: review the error, preview and effective count. Deselect the optional current entry or change the library action if appropriate.
  • Export fails: check for a silent mix, invalid frequencies, unavailable recordings or memory pressure. Try a shorter export and use WAV to separate rendering from MP3 encoding issues.
  • Audio pauses in the background: check the browser/device's media and power behavior. Layout testing does not establish uninterrupted listening on every mobile or desktop platform.

Credits and Licenses

The four original environmental recordings by Joseph Sardin / BigSoundBank, Campfire by Nox_Sound, Window rain by alxl, and Singing Bowl I / Singing Bowl II by ganapataye retain their CC0 terms. White, pink and brown noise are synthesized. Original Hz Mixer code and artwork use MIT; Lucide utility icons retain their separate notices. The lamejs MP3 encoder remains LGPL-3.0 and is independently replaceable.

Credits in the mixer footer contains full notices, recording provenance, encoder replacement instructions and an exact upstream encoder-source download. Those notices and the source download are embedded in the portable file as well as supplied with the release package. The original-code MIT license does not replace component or recording terms.

About Hz Mixer

Mix rhythmic tones with environmental recordings and generated noise. Audio generation, saved mixes and exports stay in your browser.

Binaural
One tone per ear. Stereo headphones are required.
Monaural
Two tones mixed into both channels, for headphones or speakers.
Isochronic
A pulsed carrier, shaped with Width, Softness and Depth.

Use Fixed, Sweep or Session for the frequency program. Recordings and noise have independent level, mute, solo and balance controls. Export audio as WAV or MP3, and back up editable mixes as JSON.

Full guide

Save your mix

Stored in this browser.

Export

Import mixes

Select a mix or library backup.

Privacy

Audio generation, exports and JSON imports run in this browser. Hz Mixer has no accounts, analytics or upload endpoint.

Settings, favorites and saved mixes use this browser's local storage. Clearing site data removes them. Download a library backup before changing browsers, moving the portable file or switching between the website and offline app.

The website requests app files, enabled recordings and the MP3 encoder from its host. GitHub Pages records visitor IP addresses for security. No mix settings or imported JSON are sent by Hz Mixer. Exported files are stored wherever your browser saves downloads.

The standalone HTML contains its assets and makes no runtime network requests. No microphone permission is requested.

Credits and licences

Hz Mixer 0.1.0

Original source: MIT
MIT License

Copyright (c) 2026 Hz Mixer contributors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
Recordings: CC0
# Audio sources

Downloaded on 2026-10-05 from the creator's BigSoundBank pages. Joseph Sardin identifies each recording as CC0 and explicitly permits editing, redistribution, and commercial use without required attribution. Source pages and the [site license](https://bigsoundbank.com/licenses.html) were checked before bundling. Credit is included here even though it is optional.

| Local file | Recording | Creator | Source page | Direct file | License | SHA-256 |
| --- | --- | --- | --- | --- | --- | --- |
| `cascade.mp3` | Small Cascade | Joseph Sardin | https://bigsoundbank.com/small-cascade-s0507.html | https://bigsoundbank.com/UPLOAD/mp3/0507.mp3 | CC0 1.0 | `3e6fbaa07e8ef92ba2905f90105f959fba0362b69d8695cafe59b77b5bbd3106` |
| `stream.mp3` | Small Stream #4 | Joseph Sardin | https://bigsoundbank.com/small-stream-4-s1354.html | https://bigsoundbank.com/UPLOAD/mp3/1354.mp3 | CC0 1.0 | `29c6c0498b18e24d00776d99f7be35d6e35f64c2f203dee6a1d0434f9f45a927` |
| `storm.mp3` | Rain and Thunder #2 | Joseph Sardin | https://bigsoundbank.com/rain-and-storm-2-s0740.html | https://bigsoundbank.com/UPLOAD/mp3/0740.mp3 | CC0 1.0 | `056c5296303887b650e62a6dc3282f327f8a8560c061acbf577c5e0734acdb6e` |
| `waves.mp3` | Sea Waves | Joseph Sardin | https://bigsoundbank.com/sea-waves-s0698.html | https://bigsoundbank.com/UPLOAD/mp3/0698.mp3 | CC0 1.0 | `caa64ec0ffd4319f016459b3295d3f8c6eaa5209d6e95c9c5cfd897c02797a22` |

License text: https://creativecommons.org/publicdomain/zero/1.0/

These four MP3 versions are unchanged from their downloaded originals. Playback and audio export decode environmental recordings into new buffers with a 1.5-second equal-power overlap at each loop join; this shortens each playback loop slightly. Audition these processed loop transitions before a public release.

## Freesound Additions

Originals downloaded by the maintainer on 2026-10-18. The exact original asset pages were checked on that date and each explicitly listed CC0 1.0. Singing Bowl I (original title `BELL_33`, bundled as `bell-33.wav`) and Singing Bowl II (original title `BELL 37`, bundled as `bell-37.wav`) are Tibetan bowl recordings by ganapataye. Campfire is a close field recording by Nox_Sound. Creator names and source IDs are retained even though attribution is optional under CC0.

| Bundled file | Recording | Creator | Original page | Original filename | Original SHA-256 | Bundled SHA-256 |
| --- | --- | --- | --- | --- | --- | --- |
| `campfire.mp3` | Ambiance_Campfire_Loop_Stereo.wav | Nox_Sound | https://freesound.org/people/Nox_Sound/sounds/558967/ | `558967__nox_sound__ambiance_campfire_loop_stereo.wav` | `ac533432f35aed4e4a1375c42f1dad505cfc4026d67ae38f37720ba1f56801b6` | `160e2315cf0509b77cd757cce5e4441932e1a5477265de24b02c536f838e5fc4` |
| `bell-33.wav` | BELL_33 | ganapataye | https://freesound.org/people/ganapataye/sounds/837372/ | `837372__ganapataye__bell_33.aiff` | `5956c4e2ec2d24b9632614b27a5d0d8d975aff1605e525bb7858d76013127097` | `ef33b133713348ec9c2e385facc6bdf7adba06fe800dd41828b30083b4727da4` |
| `bell-37.wav` | BELL 37 | ganapataye | https://freesound.org/people/ganapataye/sounds/837376/ | `837376__ganapataye__bell-37.aiff` | `a59503282f37586e390c9125e4a6af4355b3db49d87cb75a0d566936b7a34223` | `ba3ff1ee80bd3e4eff2ae643a94df2ee6de7501b654bae47c3565cda7f5a4743` |

Conversions use FFmpeg: `-map_metadata -1 -codec:a libmp3lame -b:a 192k` for Campfire (48 kHz stereo, 12.725542 seconds before encoding), and `-map_metadata -1 -codec:a pcm_s16le` for both bells (44.1 kHz, 16-bit stereo). No gain, trimming, filtering, resampling, or added reverb was applied. The AIFF-to-WAV conversions change the container and PCM byte order without reducing audio precision. Originals remain outside the public repository; hashes identify the supplied sources.

Campfire uses the same runtime crossfade as the other environmental layers. Bells retain their full one-shot recordings, with silence between scheduled strikes rather than a crossfaded or padded looping buffer. Playback and export use the same source files and interval clock.

## Window Rain

Rain on Window Loop by alxl: https://opengameart.org/content/rain-on-window-loop. The maintainer supplied `rain_on_window_loop.wav` on 2026-10-18. The original page was checked that day: CC0 is explicitly offered as one of several alternative licences, and the creator confirms that users may choose one. This project uses the CC0 option; attribution is optional, with credit retained here for provenance.

- Original WAV: 10.866259 seconds, stereo, 44.1 kHz, 16-bit PCM.
- Original SHA-256: `97b9405025e5ed7ed8a58d24dd7146d06e925519b1f718efda94bb85dcd1a61a`.
- Bundled file: `window-rain.mp3`, stereo 44.1 kHz, 192 kbps.
- Bundled SHA-256: `04a97826e2d94eb544f81ecb481a40accf9c527b03f2b9687552a934870aa605`.
- Conversion: FFmpeg 8.0.1, `-map_metadata -1 -codec:a libmp3lame -b:a 192k`. No gain, trimming, filtering, added reverb, or source resampling. The original remains unchanged outside the repository.
- Playback/export use the same runtime 1.5-second crossfade as the other environmental recordings; the processed repeat interval is approximately 9.366 seconds.
Icons and artwork
# Icons and Artwork

Utility/control SVGs are from the official [Lucide repository](https://github.com/lucide-icons/lucide), retrieved 2026-10-05 and 2026-10-10. Original ISC and inherited Feather MIT notices are preserved in [LICENSE](LICENSE). Files are served locally, without an icon CDN.

`info.svg`, `triangle-alert.svg`, `book-open.svg` and `arrow-left.svg` were retrieved from the same official repository on 2026-10-17. Only SVG whitespace was compacted; paths and attributes are unchanged. They use the existing Lucide licence notices.

`bell.svg` was retrieved from the official repository on 2026-10-18 for the interval-bell channels. Only SVG whitespace was compacted; paths and attributes are unchanged. It uses the existing Lucide licence notices.

`noise-pink.svg` and `noise-brown.svg` are recolored versions of Lucide's `audio-lines.svg`, made 2026-10-15. They retain the same paths and original licence notices, with pink and brown strokes respectively. Theme styling preserves these colors instead of inverting them in dark mode.

`waterfall.svg`, `stream-flow.svg`, `thunderstorm.svg` and `sea-waves.svg` are original Hz Mixer artwork drawn 2026-10-14 under the project's MIT licence. They depict a cascade, flowing stream, rain/lightning cloud and breaking sea wave. They are not modified Lucide icons.

`window-rain.svg`, drawn 2026-10-18 under MIT, is original Hz Mixer artwork depicting rain on a four-pane window. It is not a modified Lucide icon.

`campfire.svg`, drawn 2026-10-19 under MIT, is original Hz Mixer artwork depicting flames above crossed logs with small sparks. It replaces the generic flame symbol and is not a modified Lucide icon.

`mixer-waves.svg`, drawn 2026-10-15 under MIT, is the active header/favicon: a sloped three-channel console over a full-tile wave pattern. The opaque console masks the waves beneath it.

Only active icons are shipped. Unused design trials are not included in the source release or generated distributions.

`sliders-horizontal.svg` is from Lucide tag 0.468.0, retrieved from the official
repository on 2026-10-19 for source effects controls. Only whitespace was
compacted; paths and attributes are unchanged. It uses the existing Lucide notices.

`dices.svg` is from Lucide tag 0.468.0, retrieved 2026-10-19 from
https://raw.githubusercontent.com/lucide-icons/lucide/0.468.0/icons/dices.svg
for Randomize mix. Only whitespace was compacted; paths and attributes are
unchanged. It uses the existing Lucide notices.
Icon licences
ISC License

Copyright (c) 2026 Lucide Icons and Contributors

Permission to use, copy, modify, and/or distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

---

The following Lucide icons are derived from the Feather project:

airplay, alert-circle, alert-octagon, alert-triangle, aperture, arrow-down-circle, arrow-down-left, arrow-down-right, arrow-down, arrow-left-circle, arrow-left, arrow-right-circle, arrow-right, arrow-up-circle, arrow-up-left, arrow-up-right, arrow-up, at-sign, calendar, cast, check, chevron-down, chevron-left, chevron-right, chevron-up, chevrons-down, chevrons-left, chevrons-right, chevrons-up, circle, clipboard, clock, code, columns, command, compass, corner-down-left, corner-down-right, corner-left-down, corner-left-up, corner-right-down, corner-right-up, corner-up-left, corner-up-right, crosshair, database, divide-circle, divide-square, dollar-sign, download, external-link, feather, frown, hash, headphones, help-circle, info, italic, key, layout, life-buoy, link-2, link, loader, lock, log-in, log-out, maximize, meh, minimize, minimize-2, minus-circle, minus-square, minus, monitor, moon, more-horizontal, more-vertical, move, music, navigation-2, navigation, octagon, pause-circle, percent, plus-circle, plus-square, plus, power, radio, rss, search, server, share, shopping-bag, sidebar, smartphone, smile, square, table-2, tablet, target, terminal, trash-2, trash, triangle, tv, type, upload, x-circle, x-octagon, x-square, x, zoom-in, zoom-out

The MIT License (MIT) (for the icons listed above)

Copyright (c) 2013-present Cole Bemis

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

MP3 encoder: lamejs 1.2.7 / LGPL-3.0

Unmodified LAME JavaScript port by Alex Zhukov and contributors. LAME project. You may modify and replace the encoder; its separate script is not part of the MIT licence.

Download exact upstream encoder source

Encoder notice and replacement instructions
# MP3 Encoder Redistribution

Hz Mixer uses **@breezystack/lamejs 1.2.7**, Alex Zhukov and contributors' JavaScript port of LAME, under **LGPL-3.0**. It is unmodified. This component is not covered by Hz Mixer's MIT licence. No restriction on reverse engineering for debugging modifications to this library is imposed.

- [LAME project](https://lame.sourceforge.net/)
- [Upstream repository](https://github.com/gideonstele/lamejs)
- Published npm revision: `1fb0ef5fa177413107e2e107d054a9b994e3f79c`.
- [Exact corresponding upstream source, including build files](source.tar.gz), also available from [the upstream archive](https://github.com/gideonstele/lamejs/archive/1fb0ef5fa177413107e2e107d054a9b994e3f79c.tar.gz).
- [Upstream notice](LICENSE), [LGPL-3.0](COPYING.LESSER) and [GPL-3.0](COPYING) accompany every distribution.

The web build serves `lamejs.iife.js` as a separate script, loaded only for MP3 export. Replace it with a compatible `lamejs.Mp3Encoder` implementation to use your own modified encoder. The portable HTML has the exact same unmodified JavaScript in a separate `mp3-encoder` script block. You may replace that block directly in a text editor. It includes an encoder-source download in Credits. Hz Mixer's own unminified JavaScript is editable in that HTML; rebuilding is not required to replace the encoder there.

To rebuild from source, extract `source.tar.gz`, review its `package.json`, install the upstream build dependencies, and use its `npm run build` command. Replace `vendor/lamejs/lamejs.iife.js` with the resulting compatible build, and update the accompanying corresponding-source archive and notices when redistributing modifications. In Hz Mixer's source checkout, `npm run build` then produces both web and portable outputs from the substituted script. `npm ci` does not overwrite the vendored encoder. The locked npm dependency is used only to verify the pristine distribution, not to prevent replacement.

SHA-256 of the unmodified `lamejs.iife.js`: `0be202ec162aa3042d5c5c4e6288ad326cff8cec7312c2894a0a91ad2f9aeda1`.

SHA-256 of the exact upstream `source.tar.gz`: `af8f08f0ff9a13777f2ffff737b48e40019b53a4b21db270dd62e829574e2b83`.

The two complete GNU licence texts were retrieved from SPDX's official `license-list-data` text copies. The npm integrity hash is locked in Hz Mixer's `package-lock.json`. The unmodified encoder explicitly selects stereo mode and accepts separate left and right PCM arrays. MP3 remains lossy and adds codec delay/padding; WAV is the uncompressed reference.
Original LAME notice
Can I use LAME in my commercial program?  

Yes, you can, under the restrictions of the LGPL.  The easiest
way to do this is to:

1. Link to LAME as separate jar (lame.min.js or lame.all.js)

2. Fully acknowledge that you are using LAME, and give a link
   to our web site, lame.sourceforge.net

3. If you make modifications to LAME, you *must* release these
   these modifications back to the LAME project, under the LGPL.
GNU LGPL version 3
GNU LESSER GENERAL PUBLIC LICENSE
Version 3, 29 June 2007

Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

This version of the GNU Lesser General Public License incorporates the terms and conditions of version 3 of the GNU General Public License, supplemented by the additional permissions listed below.

0. Additional Definitions.

As used herein, "this License" refers to version 3 of the GNU Lesser General Public License, and the "GNU GPL" refers to version 3 of the GNU General Public License.

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An "Application" is any work that makes use of an interface provided by the Library, but which is not otherwise based on the Library. Defining a subclass of a class defined by the Library is deemed a mode of using an interface provided by the Library.

A "Combined Work" is a work produced by combining or linking an Application with the Library.  The particular version of the Library with which the Combined Work was made is also called the "Linked Version".

The "Minimal Corresponding Source" for a Combined Work means the Corresponding Source for the Combined Work, excluding any source code for portions of the Combined Work that, considered in isolation, are based on the Application, and not on the Linked Version.

The "Corresponding Application Code" for a Combined Work means the object code and/or source code for the Application, including any data and utility programs needed for reproducing the Combined Work from the Application, but excluding the System Libraries of the Combined Work.

1. Exception to Section 3 of the GNU GPL.
You may convey a covered work under sections 3 and 4 of this License without being bound by section 3 of the GNU GPL.

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The object code form of an Application may incorporate material from a header file that is part of the Library.  You may convey such object code under terms of your choice, provided that, if the incorporated material is not limited to numerical parameters, data structure layouts and accessors, or small macros, inline functions and templates (ten or fewer lines in length), you do both of the following:

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If the Library as you received it specifies that a proxy can decide whether future versions of the GNU Lesser General Public License shall
apply, that proxy's public statement of acceptance of any version is permanent authorization for you to choose that version for the Library.

GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007

Copyright © 2007 Free Software Foundation, Inc. <http://fsf.org/>

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Preamble

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     c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.

     d) If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so.

A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.

6. Conveying Non-Source Forms.
You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:

     a) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.

     b) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge.

     c) Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b.

     d) Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements.

     e) Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d.

A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work.

A “User Product” is either (1) a “consumer product”, which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, “normally used” refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product.

“Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.

If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).

The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.

Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.

7. Additional Terms.
“Additional permissions” are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions.

When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission.

Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms:

     a) Disclaiming warranty or limiting liability differently from the terms of sections 15 and 16 of this License; or

     b) Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or

     c) Prohibiting misrepresentation of the origin of that material, or requiring that modified versions of such material be marked in reasonable ways as different from the original version; or

     d) Limiting the use for publicity purposes of names of licensors or authors of the material; or

     e) Declining to grant rights under trademark law for use of some trade names, trademarks, or service marks; or

     f) Requiring indemnification of licensors and authors of that material by anyone who conveys the material (or modified versions of it) with contractual assumptions of liability to the recipient, for any liability that these contractual assumptions directly impose on those licensors and authors.

All other non-permissive additional terms are considered “further restrictions” within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying.

If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms.

Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way.

8. Termination.
You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11).

However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10.

9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.

10. Automatic Licensing of Downstream Recipients.
Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License.

An “entity transaction” is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party's predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts.

You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it.

11. Patents.
A “contributor” is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor's “contributor version”.

A contributor's “essential patent claims” are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, “control” includes the right to grant patent sublicenses in a manner consistent with the requirements of this License.

Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor's essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version.

In the following three paragraphs, a “patent license” is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To “grant” such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party.

If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. “Knowingly relying” means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient's use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid.

If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it.

A patent license is “discriminatory” if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007.

Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law.

12. No Surrender of Others' Freedom.
If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program.

13. Use with the GNU Affero General Public License.
Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such.

14. Revised Versions of this License.
The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.

Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License “or any later version” applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation.

If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Program.

Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version.

15. Disclaimer of Warranty.
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

16. Limitation of Liability.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

17. Interpretation of Sections 15 and 16.
If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee.

END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Programs

If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.

To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.

     <one line to give the program's name and a brief idea of what it does.>
     Copyright (C) <year>  <name of author>

     This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

     This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

     You should have received a copy of the GNU General Public License along with this program.  If not, see <http://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode:

     <program>  Copyright (C) <year>  <name of author>
     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
     This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, your program's commands might be different; for a GUI interface, you would use an “about box”.

You should also get your employer (if you work as a programmer) or school, if any, to sign a “copyright disclaimer” for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see <http://www.gnu.org/licenses/>.

The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read <http://www.gnu.org/philosophy/why-not-lgpl.html>.
GNU GPL version 3
GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007

Copyright © 2007 Free Software Foundation, Inc. <https://fsf.org/>

Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

Preamble

The GNU General Public License is a free, copyleft license for software and other kinds of works.

The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program--to make sure it remains free software for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other work released this way by its authors. You can apply it to your programs, too.

When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things.

To protect your rights, we need to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others.

For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.

Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it.

For the developers' and authors' protection, the GPL clearly explains that there is no warranty for this free software. For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.

Some devices are designed to deny users access to install or run modified versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting users' freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions of the GPL, as needed to protect the freedom of users.

Finally, every program is threatened constantly by software patents. States should not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents cannot be used to render the program non-free.

The precise terms and conditions for copying, distribution and modification follow.

TERMS AND CONDITIONS

0. Definitions.

“This License” refers to version 3 of the GNU General Public License.

“Copyright” also means copyright-like laws that apply to other kinds of works, such as semiconductor masks.

“The Program” refers to any copyrightable work licensed under this License. Each licensee is addressed as “you”. “Licensees” and “recipients” may be individuals or organizations.

To “modify” a work means to copy from or adapt all or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a “modified version” of the earlier work or a work “based on” the earlier work.

A “covered work” means either the unmodified Program or a work based on the Program.

To “propagate” a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well.

To “convey” a work means any kind of propagation that enables other parties to make or receive copies. Mere interaction with a user through a computer network, with no transfer of a copy, is not conveying.

An interactive user interface displays “Appropriate Legal Notices” to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion.

1. Source Code.
The “source code” for a work means the preferred form of the work for making modifications to it. “Object code” means any non-source form of a work.

A “Standard Interface” means an interface that either is an official standard defined by a recognized standards body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working in that language.

The “System Libraries” of an executable work include anything, other than the work as a whole, that (a) is included in the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use of the work with that Major Component, or to implement a Standard Interface for which an implementation is available to the public in source code form. A “Major Component”, in this context, means a major essential component (kernel, window system, and so on) of the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code interpreter used to run it.

The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However, it does not include the work's System Libraries, or general-purpose tools or generally available free programs which are used unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work.

The Corresponding Source need not include anything that users can regenerate automatically from other parts of the Corresponding Source.

The Corresponding Source for a work in source code form is that same work.

2. Basic Permissions.
All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges your rights of fair use or other equivalent, as provided by copyright law.

You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them from making any copies of your copyrighted material outside their relationship with you.

Conveying under any other circumstances is permitted solely under the conditions stated below. Sublicensing is not allowed; section 10 makes it unnecessary.

3. Protecting Users' Legal Rights From Anti-Circumvention Law.
No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling obligations under article 11 of the WIPO copyright treaty adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention of such measures.

When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work's users, your or third parties' legal rights to forbid circumvention of technological measures.

4. Conveying Verbatim Copies.
You may convey verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program.

You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee.

5. Conveying Modified Source Versions.
You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions:

     a) The work must carry prominent notices stating that you modified it, and giving a relevant date.

     b) The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to “keep intact all notices”.

     c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.

     d) If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so.

A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.

6. Conveying Non-Source Forms.
You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:

     a) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.

     b) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge.

     c) Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b.

     d) Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements.

     e) Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d.

A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work.

A “User Product” is either (1) a “consumer product”, which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, “normally used” refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product.

“Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.

If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).

The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.

Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.

7. Additional Terms.
“Additional permissions” are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions.

When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission.

Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms:

     a) Disclaiming warranty or limiting liability differently from the terms of sections 15 and 16 of this License; or

     b) Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or

     c) Prohibiting misrepresentation of the origin of that material, or requiring that modified versions of such material be marked in reasonable ways as different from the original version; or

     d) Limiting the use for publicity purposes of names of licensors or authors of the material; or

     e) Declining to grant rights under trademark law for use of some trade names, trademarks, or service marks; or

     f) Requiring indemnification of licensors and authors of that material by anyone who conveys the material (or modified versions of it) with contractual assumptions of liability to the recipient, for any liability that these contractual assumptions directly impose on those licensors and authors.

All other non-permissive additional terms are considered “further restrictions” within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying.

If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms.

Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way.

8. Termination.
You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11).

However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10.

9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.

10. Automatic Licensing of Downstream Recipients.
Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License.

An “entity transaction” is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party's predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts.

You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it.

11. Patents.
A “contributor” is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor's “contributor version”.

A contributor's “essential patent claims” are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, “control” includes the right to grant patent sublicenses in a manner consistent with the requirements of this License.

Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor's essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version.

In the following three paragraphs, a “patent license” is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To “grant” such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party.

If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. “Knowingly relying” means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient's use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid.

If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it.

A patent license is “discriminatory” if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007.

Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law.

12. No Surrender of Others' Freedom.
If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program.

13. Use with the GNU Affero General Public License.
Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such.

14. Revised Versions of this License.
The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.

Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License “or any later version” applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation.

If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Program.

Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version.

15. Disclaimer of Warranty.
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

16. Limitation of Liability.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

17. Interpretation of Sections 15 and 16.
If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee.

END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Programs

If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.

To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.

     <one line to give the program's name and a brief idea of what it does.>
     Copyright (C) <year>  <name of author>

     This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

     This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

     You should have received a copy of the GNU General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode:

     <program>  Copyright (C) <year>  <name of author>
     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
     This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, your program's commands might be different; for a GUI interface, you would use an “about box”.

You should also get your employer (if you work as a programmer) or school, if any, to sign a “copyright disclaimer” for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see <https://www.gnu.org/licenses/>.

The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read <https://www.gnu.org/philosophy/why-not-lgpl.html>.