@vikasietum_tecknology/record-rtc
Version:
record-rtc is a library based on recordrtc library. In this forked version of the original library we have optimized the memory management. The video recording is stored in IndexDB in chunks.
288 lines (248 loc) • 8.89 kB
JavaScript
// ______________________
// WebAssemblyRecorder.js
/**
* WebAssemblyRecorder lets you create webm videos in JavaScript via WebAssembly. The library consumes raw RGBA32 buffers (4 bytes per pixel) and turns them into a webm video with the given framerate and quality. This makes it compatible out-of-the-box with ImageData from a CANVAS. With realtime mode you can also use webm-wasm for streaming webm videos.
* @summary Video recording feature in Chrome, Firefox and maybe Edge.
* @license {@link https://github.com/muaz-khan/RecordRTC/blob/master/LICENSE|MIT}
* @author {@link https://MuazKhan.com|Muaz Khan}
* @typedef WebAssemblyRecorder
* @class
* @example
* var recorder = new WebAssemblyRecorder(mediaStream);
* recorder.record();
* recorder.stop(function(blob) {
* video.src = URL.createObjectURL(blob);
* });
* @see {@link https://github.com/muaz-khan/RecordRTC|RecordRTC Source Code}
* @param {MediaStream} mediaStream - MediaStream object fetched using getUserMedia API or generated using captureStreamUntilEnded or WebAudio API.
* @param {object} config - {webAssemblyPath:'webm-wasm.wasm',workerPath: 'webm-worker.js', frameRate: 30, width: 1920, height: 1080, bitrate: 1024, realtime: true}
*/
function WebAssemblyRecorder(stream, config) {
// based on: github.com/GoogleChromeLabs/webm-wasm
if (
typeof ReadableStream === "undefined" ||
typeof WritableStream === "undefined"
) {
// because it fixes readable/writable streams issues
console.error(
"Following polyfill is strongly recommended: https://unpkg.com/@mattiasbuelens/web-streams-polyfill/dist/polyfill.min.js"
);
}
config = config || {};
config.width = config.width || 640;
config.height = config.height || 480;
config.frameRate = config.frameRate || 30;
config.bitrate = config.bitrate || 1200;
config.realtime = config.realtime || true;
function createBufferURL(buffer, type) {
return URL.createObjectURL(
new Blob([buffer], {
type: type || "",
})
);
}
var finished;
function cameraStream() {
return new ReadableStream({
start: function(controller) {
var cvs = document.createElement("canvas");
var video = document.createElement("video");
var first = true;
video.srcObject = stream;
video.muted = true;
video.height = config.height;
video.width = config.width;
video.volume = 0;
video.onplaying = function() {
cvs.width = config.width;
cvs.height = config.height;
var ctx = cvs.getContext("2d");
var frameTimeout = 1000 / config.frameRate;
var cameraTimer = setInterval(function f() {
if (finished) {
clearInterval(cameraTimer);
controller.close();
}
if (first) {
first = false;
if (config.onVideoProcessStarted) {
config.onVideoProcessStarted();
}
}
ctx.drawImage(video, 0, 0);
if (controller._controlledReadableStream.state !== "closed") {
try {
controller.enqueue(
ctx.getImageData(0, 0, config.width, config.height)
);
} catch (e) {}
}
}, frameTimeout);
};
video.play();
},
});
}
var worker;
function startRecording(stream, buffer) {
if (!config.workerPath && !buffer) {
finished = false;
// is it safe to use @latest ?
fetch("https://unpkg.com/webm-wasm@latest/dist/webm-worker.js").then(
function(r) {
r.arrayBuffer().then(function(buffer) {
startRecording(stream, buffer);
});
}
);
return;
}
if (!config.workerPath && buffer instanceof ArrayBuffer) {
var blob = new Blob([buffer], {
type: "text/javascript",
});
config.workerPath = URL.createObjectURL(blob);
}
if (!config.workerPath) {
console.error("workerPath parameter is missing.");
}
worker = new Worker(config.workerPath);
worker.postMessage(
config.webAssemblyPath ||
"https://unpkg.com/webm-wasm@latest/dist/webm-wasm.wasm"
);
worker.addEventListener("message", function(event) {
if (event.data === "READY") {
worker.postMessage({
width: config.width,
height: config.height,
bitrate: config.bitrate || 1200,
timebaseDen: config.frameRate || 30,
realtime: config.realtime,
});
cameraStream().pipeTo(
new WritableStream({
write: function(image) {
if (finished) {
console.error("Got image, but recorder is finished!");
return;
}
worker.postMessage(image.data.buffer, [image.data.buffer]);
},
})
);
} else if (!!event.data) {
if (!isPaused) {
arrayOfBuffers.push(event.data);
}
}
});
}
/**
* This method records video.
* @method
* @memberof WebAssemblyRecorder
* @example
* recorder.record();
*/
this.record = function() {
arrayOfBuffers = [];
isPaused = false;
this.blob = null;
startRecording(stream);
if (typeof config.initCallback === "function") {
config.initCallback();
}
};
var isPaused;
/**
* This method pauses the recording process.
* @method
* @memberof WebAssemblyRecorder
* @example
* recorder.pause();
*/
this.pause = function() {
isPaused = true;
};
/**
* This method resumes the recording process.
* @method
* @memberof WebAssemblyRecorder
* @example
* recorder.resume();
*/
this.resume = function() {
isPaused = false;
};
function terminate(callback) {
if (!worker) {
if (callback) {
callback();
}
return;
}
// Wait for null event data to indicate that the encoding is complete
worker.addEventListener("message", function(event) {
if (event.data === null) {
worker.terminate();
worker = null;
if (callback) {
callback();
}
}
});
worker.postMessage(null);
}
var arrayOfBuffers = [];
/**
* This method stops recording video.
* @param {function} callback - Callback function, that is used to pass recorded blob back to the callee.
* @method
* @memberof WebAssemblyRecorder
* @example
* recorder.stop(function(blob) {
* video.src = URL.createObjectURL(blob);
* });
*/
this.stop = function(callback) {
finished = true;
var recorder = this;
terminate(function() {
recorder.blob = new Blob(arrayOfBuffers, {
type: "video/webm",
});
callback(recorder.blob);
});
};
// for debugging
this.name = "WebAssemblyRecorder";
this.toString = function() {
return this.name;
};
/**
* This method resets currently recorded data.
* @method
* @memberof WebAssemblyRecorder
* @example
* recorder.clearRecordedData();
*/
this.clearRecordedData = function() {
arrayOfBuffers = [];
isPaused = false;
this.blob = null;
// todo: if recording-ON then STOP it first
};
/**
* @property {Blob} blob - The recorded blob object.
* @memberof WebAssemblyRecorder
* @example
* recorder.stop(function(){
* var blob = recorder.blob;
* });
*/
this.blob = null;
}
if (typeof RecordRTC !== "undefined") {
RecordRTC.WebAssemblyRecorder = WebAssemblyRecorder;
}