<!doctype html>
<html lang="en-us">

<head>
    <title>whisper.cpp : WASM example</title>

    <style>
        body {
            background-color: white;
        }

        #output {
            width: 100%;
            height: 100%;
            margin: 0 auto;
            margin-top: 10px;
            border-left: 0px;
            border-right: 0px;
            padding-left: 0px;
            padding-right: 0px;
            display: block;
            background-color: black;
            color: white;
            font-size: 10px;
            font-family: 'Lucida Console', Monaco, monospace;
            outline: none;
            white-space: pre;
            overflow-wrap: normal;
            overflow-x: scroll;
        }
    </style>
</head>

<body>
    <div id="main-container">
        <div id="warning" style="display: none; padding: 1rem;">
            <b style="color: red ; font-size: large;">Warning: your browser does not support SharedArrayBuffer please
                try open the page in a new tab.
            </b> <a href="https://radames-whisper-wasm.hf.space"
                target="_blank">https://radames-whisper-wasm.hf.space</a>
        </div>
        <b>Minimal <a target="_blank" href="https://github.com/ggerganov/whisper.cpp">whisper.cpp</a> example running
            fully in the browser</b>

        <br><br>

        Usage instructions:<br>
        <ul>
            <li>Load a ggml model file (you can obtain one from <a target="_blank"
                    href="https://ggml.ggerganov.com/">here</a>, recommended: <b>tiny</b> or <b>base</b>)</li>
            <li>Select audio file to transcribe or record audio from the microphone (sample: <a target="_blank"
                    href="https://whisper.ggerganov.com/jfk.wav">jfk.wav</a>)</li>
            <li>Click on the "Transcribe" button to start the transcription</li>
        </ul>

        Note that the computation is quite heavy and may take a few seconds to complete.<br>
        The transcription results will be displayed in the text area below.<br><br>
        <b>Important: your browser must support WASM SIMD instructions for this to work.</b>

        <br><br>
        <hr>

        <div id="model">
            Whisper model: <span id="model-whisper-status"></span>
            <button id="fetch-whisper-tiny-en" onclick="loadWhisper('tiny.en')">tiny.en (75 MB)</button>
            <button id="fetch-whisper-tiny" onclick="loadWhisper('tiny')">tiny (75 MB)</button>
            <button id="fetch-whisper-base-en" onclick="loadWhisper('base.en')">base.en (142 MB)</button>
            <button id="fetch-whisper-base" onclick="loadWhisper('base')">base (142 MB)</button>
            <span id="fetch-whisper-progress"></span>

            <input type="file" id="whisper-file" name="file" onchange="loadFile(event, 'whisper.bin')" />
        </div>

        <br>

        <!-- radio button to select between file upload or microphone -->
        <div id="input">
            Input:
            <input type="radio" id="file" name="input" value="file" checked="checked" onchange="changeInput('file')" />
            File
            <input type="radio" id="mic" name="input" value="mic" onchange="changeInput('mic')" /> Microphone
        </div>

        <br>

        <div id="input_file">
            Audio file:
            <input type="file" id="file" name="file" onchange="loadAudio(event)" />
        </div>

        <div id="input_mic" style="display: none;">
            Microphone:
            <button id="start" onclick="startRecording()">Start</button>
            <button id="stop" onclick="stopRecording()" disabled>Stop</button>

            <!-- progress bar to show recording progress -->
            <br><br>
            <div id="progress" style="display: none;">
                <div id="progress-bar" style="width: 0%; height: 10px; background-color: #4CAF50;"></div>
                <div id="progress-text">0%</div>
            </div>
        </div>

        <audio controls="controls" id="audio" loop hidden>
            Your browser does not support the &lt;audio&gt; tag.
            <source id="source" src="" type="audio/wav" />
        </audio>

        <hr><br>

        <table>
            <tr>
                <td>
                    Language:
                    <select id="language" name="language">
                        <option value="en">English</option>
                        <option value="ar">Arabic</option>
                        <option value="hy">Armenian</option>
                        <option value="az">Azerbaijani</option>
                        <option value="eu">Basque</option>
                        <option value="be">Belarusian</option>
                        <option value="bn">Bengali</option>
                        <option value="bg">Bulgarian</option>
                        <option value="ca">Catalan</option>
                        <option value="zh">Chinese</option>
                        <option value="hr">Croatian</option>
                        <option value="cs">Czech</option>
                        <option value="da">Danish</option>
                        <option value="nl">Dutch</option>
                        <option value="en">English</option>
                        <option value="et">Estonian</option>
                        <option value="tl">Filipino</option>
                        <option value="fi">Finnish</option>
                        <option value="fr">French</option>
                        <option value="gl">Galician</option>
                        <option value="ka">Georgian</option>
                        <option value="de">German</option>
                        <option value="el">Greek</option>
                        <option value="gu">Gujarati</option>
                        <option value="iw">Hebrew</option>
                        <option value="hi">Hindi</option>
                        <option value="hu">Hungarian</option>
                        <option value="is">Icelandic</option>
                        <option value="id">Indonesian</option>
                        <option value="ga">Irish</option>
                        <option value="it">Italian</option>
                        <option value="ja">Japanese</option>
                        <option value="kn">Kannada</option>
                        <option value="ko">Korean</option>
                        <option value="la">Latin</option>
                        <option value="lv">Latvian</option>
                        <option value="lt">Lithuanian</option>
                        <option value="mk">Macedonian</option>
                        <option value="ms">Malay</option>
                        <option value="mt">Maltese</option>
                        <option value="no">Norwegian</option>
                        <option value="fa">Persian</option>
                        <option value="pl">Polish</option>
                        <option value="pt">Portuguese</option>
                        <option value="ro">Romanian</option>
                        <option value="ru">Russian</option>
                        <option value="sr">Serbian</option>
                        <option value="sk">Slovak</option>
                        <option value="sl">Slovenian</option>
                        <option value="es">Spanish</option>
                        <option value="sw">Swahili</option>
                        <option value="sv">Swedish</option>
                        <option value="ta">Tamil</option>
                        <option value="te">Telugu</option>
                        <option value="th">Thai</option>
                        <option value="tr">Turkish</option>
                        <option value="uk">Ukrainian</option>
                        <option value="ur">Urdu</option>
                        <option value="vi">Vietnamese</option>
                        <option value="cy">Welsh</option>
                        <option value="yi">Yiddish</option>
                    </select>
                </td>
                <td>
                    <button onclick="onProcess(false);">Transcribe</button>
                </td>
                <td>
                    <button onclick="onProcess(true);">Translate</button>
                </td>
            </tr>
        </table>

        <br>

        <!-- textarea with height filling the rest of the page -->
        <textarea id="output" rows="20"></textarea>

        <br><br>

        <div class="cell-version">
            <span>
                |
                Build time: <span class="nav-link">Mon Jan 16 11:57:35 2023</span> |
                Commit hash: <a class="nav-link" target="_blank"
                    href="https://github.com/ggerganov/whisper.cpp/commit/49b529ba">49b529ba</a> |
                Commit subject: <span class="nav-link">whisper.android : add support for loading directly from asset in
                    C (#415)</span> |
                <a class="nav-link" target="_blank"
                    href="https://github.com/ggerganov/whisper.cpp/tree/master/examples/whisper.wasm">Source Code</a> |
            </span>
        </div>
    </div>

    <script type="text/javascript" src="helpers.js"></script>
    <script type='text/javascript'>
        document.addEventListener("DOMContentLoaded", () => {
            //check is shared array buffer is supported
            if (!window.SharedArrayBuffer) {
                document.querySelector("#warning").style.display = "block";
            }
        })
        // TODO: convert audio buffer to WAV
        function setAudio(audio) {
            //if (audio) {
            //    // convert to 16-bit PCM
            //    var blob = new Blob([audio], { type: 'audio/wav' });
            //    var url = URL.createObjectURL(blob);
            //    document.getElementById('source').src = url;
            //    document.getElementById('audio').hidden = false;
            //    document.getElementById('audio').loop = false;
            //    document.getElementById('audio').load();
            //} else {
            //    document.getElementById('audio').hidden = true;
            //}
        }

        function changeInput(input) {
            if (input == 'file') {
                document.getElementById('input_file').style.display = 'block';
                document.getElementById('input_mic').style.display = 'none';
                document.getElementById('progress').style.display = 'none';
            } else {
                document.getElementById('input_file').style.display = 'none';
                document.getElementById('input_mic').style.display = 'block';
                document.getElementById('progress').style.display = 'block';
            }
        }

        var Module = {
            print: printTextarea,
            printErr: printTextarea,
            setStatus: function (text) {
                printTextarea('js: ' + text);
            },
            monitorRunDependencies: function (left) {
            }
        };

        // web audio context
        var context = null;

        // audio data
        var audio = null;

        // the whisper instance
        var instance = null;
        var model_whisper = '';

        // helper function
        function convertTypedArray(src, type) {
            var buffer = new ArrayBuffer(src.byteLength);
            var baseView = new src.constructor(buffer).set(src);
            return new type(buffer);
        }

        //
        // load model
        //

        let dbVersion = 1
        let dbName = 'whisper.ggerganov.com';
        let indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB

        function storeFS(fname, buf) {
            // write to WASM file using FS_createDataFile
            // if the file exists, delete it
            try {
                Module.FS_unlink(fname);
            } catch (e) {
                // ignore
            }

            Module.FS_createDataFile("/", fname, buf, true, true);

            model_whisper = fname;

            document.getElementById('model-whisper-status').innerHTML = 'loaded "' + model_whisper + '"!';

            printTextarea('storeFS: stored model: ' + fname + ' size: ' + buf.length);
        }

        function loadFile(event, fname) {
            var file = event.target.files[0] || null;
            if (file == null) {
                return;
            }

            printTextarea("loadFile: loading model: " + file.name + ", size: " + file.size + " bytes");
            printTextarea('loadFile: please wait ...');

            var reader = new FileReader();
            reader.onload = function (event) {
                var buf = new Uint8Array(reader.result);
                storeFS(fname, buf);
            }
            reader.readAsArrayBuffer(file);

            document.getElementById('fetch-whisper-tiny-en').style.display = 'none';
            document.getElementById('fetch-whisper-base-en').style.display = 'none';
            document.getElementById('fetch-whisper-tiny').style.display = 'none';
            document.getElementById('fetch-whisper-base').style.display = 'none';
            document.getElementById('whisper-file').style.display = 'none';
            document.getElementById('model-whisper-status').innerHTML = 'loaded model: ' + file.name;
        }

        function loadWhisper(model) {
            let urls = {
                'tiny.en': 'models/ggml-tiny.en.bin',
                'tiny': 'models/ggml-tiny.bin',
                'base.en': 'models/ggml-base.en.bin',
                'base': 'models/ggml-base.bin',
            };

            let sizes = {
                'tiny.en': 75,
                'tiny': 75,
                'base.en': 142,
                'base': 142,
            };

            let url = urls[model];
            let dst = 'whisper.bin';
            let size_mb = sizes[model];

            model_whisper = model;

            document.getElementById('fetch-whisper-tiny-en').style.display = 'none';
            document.getElementById('fetch-whisper-base-en').style.display = 'none';
            document.getElementById('fetch-whisper-tiny').style.display = 'none';
            document.getElementById('fetch-whisper-base').style.display = 'none';
            document.getElementById('whisper-file').style.display = 'none';
            document.getElementById('model-whisper-status').innerHTML = 'loading model: ' + model;

            cbProgress = function (p) {
                let el = document.getElementById('fetch-whisper-progress');
                el.innerHTML = Math.round(100 * p) + '%';
            };

            cbCancel = function () {
                var el;
                el = document.getElementById('fetch-whisper-tiny-en'); if (el) el.style.display = 'inline-block';
                el = document.getElementById('fetch-whisper-base-en'); if (el) el.style.display = 'inline-block';
                el = document.getElementById('fetch-whisper-tiny'); if (el) el.style.display = 'inline-block';
                el = document.getElementById('fetch-whisper-base'); if (el) el.style.display = 'inline-block';
                el = document.getElementById('whisper-file'); if (el) el.style.display = 'inline-block';
                el = document.getElementById('model-whisper-status'); if (el) el.innerHTML = '';
            };

            loadRemote(url, dst, size_mb, cbProgress, storeFS, cbCancel, printTextarea);
        }

        //
        // audio file
        //

        const kMaxAudio_s = 120;
        const kSampleRate = 16000;

        window.AudioContext = window.AudioContext || window.webkitAudioContext;
        window.OfflineAudioContext = window.OfflineAudioContext || window.webkitOfflineAudioContext;

        function loadAudio(event) {
            if (!context) {
                context = new AudioContext({
                    sampleRate: kSampleRate,
                    channelCount: 1,
                    echoCancellation: false,
                    autoGainControl: true,
                    noiseSuppression: true,
                });
            }

            var file = event.target.files[0] || null;
            if (file == null) {
                return;
            }

            printTextarea('js: loading audio: ' + file.name + ', size: ' + file.size + ' bytes');
            printTextarea('js: please wait ...');

            var reader = new FileReader();
            reader.onload = function (event) {
                var buf = new Uint8Array(reader.result);

                context.decodeAudioData(buf.buffer, function (audioBuffer) {
                    var offlineContext = new OfflineAudioContext(audioBuffer.numberOfChannels, audioBuffer.length, audioBuffer.sampleRate);
                    var source = offlineContext.createBufferSource();
                    source.buffer = audioBuffer;
                    source.connect(offlineContext.destination);
                    source.start(0);

                    offlineContext.startRendering().then(function (renderedBuffer) {
                        audio = renderedBuffer.getChannelData(0);
                        printTextarea('js: audio loaded, size: ' + audio.length);

                        // truncate to first 30 seconds
                        if (audio.length > kMaxAudio_s * kSampleRate) {
                            audio = audio.slice(0, kMaxAudio_s * kSampleRate);
                            printTextarea('js: truncated audio to first ' + kMaxAudio_s + ' seconds');
                        }

                        setAudio(audio);
                    });
                }, function (e) {
                    printTextarea('js: error decoding audio: ' + e);
                    audio = null;
                    setAudio(audio);
                });
            }
            reader.readAsArrayBuffer(file);
        }

        //
        // microphone
        //

        var mediaRecorder = null;
        var doRecording = false;
        var startTime = 0;

        function stopRecording() {
            doRecording = false;
        }

        // record up to kMaxAudio_s seconds of audio from the microphone
        // check if doRecording is false every 1000 ms and stop recording if so
        // update progress information
        function startRecording() {
            if (!context) {
                context = new AudioContext({
                    sampleRate: kSampleRate,
                    channelCount: 1,
                    echoCancellation: false,
                    autoGainControl: true,
                    noiseSuppression: true,
                });
            }

            document.getElementById('start').disabled = true;
            document.getElementById('stop').disabled = false;

            document.getElementById('progress-bar').style.width = '0%';
            document.getElementById('progress-text').innerHTML = '0%';

            doRecording = true;
            startTime = Date.now();

            var chunks = [];
            var stream = null;

            navigator.mediaDevices.getUserMedia({ audio: true, video: false })
                .then(function (s) {
                    stream = s;
                    mediaRecorder = new MediaRecorder(stream);
                    mediaRecorder.ondataavailable = function (e) {
                        chunks.push(e.data);
                    };
                    mediaRecorder.onstop = function (e) {
                        var blob = new Blob(chunks, { 'type': 'audio/ogg; codecs=opus' });
                        chunks = [];

                        document.getElementById('start').disabled = false;
                        document.getElementById('stop').disabled = true;

                        var reader = new FileReader();
                        reader.onload = function (event) {
                            var buf = new Uint8Array(reader.result);

                            context.decodeAudioData(buf.buffer, function (audioBuffer) {
                                var offlineContext = new OfflineAudioContext(audioBuffer.numberOfChannels, audioBuffer.length, audioBuffer.sampleRate);
                                var source = offlineContext.createBufferSource();
                                source.buffer = audioBuffer;
                                source.connect(offlineContext.destination);
                                source.start(0);

                                offlineContext.startRendering().then(function (renderedBuffer) {
                                    audio = renderedBuffer.getChannelData(0);
                                    printTextarea('js: audio recorded, size: ' + audio.length);

                                    // truncate to first 30 seconds
                                    if (audio.length > kMaxAudio_s * kSampleRate) {
                                        audio = audio.slice(0, kMaxAudio_s * kSampleRate);
                                        printTextarea('js: truncated audio to first ' + kMaxAudio_s + ' seconds');
                                    }
                                    setAudio(audio);
                                });
                            }, function (e) {
                                printTextarea('js: error decoding audio: ' + e);
                                audio = null;
                                setAudio(audio);
                            });
                        }

                        reader.readAsArrayBuffer(blob);
                    };
                    mediaRecorder.start();
                })
                .catch(function (err) {
                    printTextarea('js: error getting audio stream: ' + err);
                });

            var interval = setInterval(function () {
                if (!doRecording) {
                    clearInterval(interval);
                    mediaRecorder.stop();
                    stream.getTracks().forEach(function (track) {
                        track.stop();
                    });
                }

                document.getElementById('progress-bar').style.width = (100 * (Date.now() - startTime) / 1000 / kMaxAudio_s) + '%';
                document.getElementById('progress-text').innerHTML = (100 * (Date.now() - startTime) / 1000 / kMaxAudio_s).toFixed(0) + '%';
            }, 1000);

            printTextarea('js: recording ...');

            setTimeout(function () {
                if (doRecording) {
                    printTextarea('js: recording stopped after ' + kMaxAudio_s + ' seconds');
                    stopRecording();
                }
            }, kMaxAudio_s * 1000);
        }

        //
        // transcribe
        //

        function onProcess(translate) {
            if (!instance) {
                instance = Module.init('whisper.bin');

                if (instance) {
                    printTextarea("js: whisper initialized, instance: " + instance);
                    document.getElementById('model').innerHTML = 'Model loaded: ' + model_whisper;
                }
            }

            if (!instance) {
                printTextarea("js: failed to initialize whisper");
                return;
            }

            if (!audio) {
                printTextarea("js: no audio data");
                return;
            }

            if (instance) {
                printTextarea('');
                printTextarea('js: processing - this might take a while ...');
                printTextarea('');

                setTimeout(function () {
                    var ret = Module.full_default(instance, audio, document.getElementById('language').value, translate);
                    console.log('js: full_default returned: ' + ret);
                    if (ret) {
                        printTextarea("js: whisper returned: " + ret);
                    }
                }, 100);
            }
        }
    </script>
    <script type="text/javascript" src="main.js"></script>
</body>

</html>