First release

node_modules/mux.js/lib/aac/index.js

@@ -0,0 +1,131 @@
+/**
+ * mux.js
+ *
+ * Copyright (c) Brightcove
+ * Licensed Apache-2.0 https://github.com/videojs/mux.js/blob/master/LICENSE
+ *
+ * A stream-based aac to mp4 converter. This utility can be used to
+ * deliver mp4s to a SourceBuffer on platforms that support native
+ * Media Source Extensions.
+ */
+'use strict';
+var Stream = require('../utils/stream.js');
+var aacUtils = require('./utils');
+
+// Constants
+var AacStream;
+
+/**
+ * Splits an incoming stream of binary data into ADTS and ID3 Frames.
+ */
+
+AacStream = function() {
+  var
+    everything = new Uint8Array(),
+    timeStamp = 0;
+
+  AacStream.prototype.init.call(this);
+
+  this.setTimestamp = function(timestamp) {
+    timeStamp = timestamp;
+  };
+
+  this.push = function(bytes) {
+    var
+      frameSize = 0,
+      byteIndex = 0,
+      bytesLeft,
+      chunk,
+      packet,
+      tempLength;
+
+    // If there are bytes remaining from the last segment, prepend them to the
+    // bytes that were pushed in
+    if (everything.length) {
+      tempLength = everything.length;
+      everything = new Uint8Array(bytes.byteLength + tempLength);
+      everything.set(everything.subarray(0, tempLength));
+      everything.set(bytes, tempLength);
+    } else {
+      everything = bytes;
+    }
+
+    while (everything.length - byteIndex >= 3) {
+      if ((everything[byteIndex] === 'I'.charCodeAt(0)) &&
+          (everything[byteIndex + 1] === 'D'.charCodeAt(0)) &&
+          (everything[byteIndex + 2] === '3'.charCodeAt(0))) {
+
+        // Exit early because we don't have enough to parse
+        // the ID3 tag header
+        if (everything.length - byteIndex < 10) {
+          break;
+        }
+
+        // check framesize
+        frameSize = aacUtils.parseId3TagSize(everything, byteIndex);
+
+        // Exit early if we don't have enough in the buffer
+        // to emit a full packet
+        // Add to byteIndex to support multiple ID3 tags in sequence
+        if (byteIndex + frameSize > everything.length) {
+          break;
+        }
+        chunk = {
+          type: 'timed-metadata',
+          data: everything.subarray(byteIndex, byteIndex + frameSize)
+        };
+        this.trigger('data', chunk);
+        byteIndex += frameSize;
+        continue;
+      } else if (((everything[byteIndex] & 0xff) === 0xff) &&
+                 ((everything[byteIndex + 1] & 0xf0) === 0xf0)) {
+
+        // Exit early because we don't have enough to parse
+        // the ADTS frame header
+        if (everything.length - byteIndex < 7) {
+          break;
+        }
+
+        frameSize = aacUtils.parseAdtsSize(everything, byteIndex);
+
+        // Exit early if we don't have enough in the buffer
+        // to emit a full packet
+        if (byteIndex + frameSize > everything.length) {
+          break;
+        }
+
+        packet = {
+          type: 'audio',
+          data: everything.subarray(byteIndex, byteIndex + frameSize),
+          pts: timeStamp,
+          dts: timeStamp
+        };
+        this.trigger('data', packet);
+        byteIndex += frameSize;
+        continue;
+      }
+      byteIndex++;
+    }
+    bytesLeft = everything.length - byteIndex;
+
+    if (bytesLeft > 0) {
+      everything = everything.subarray(byteIndex);
+    } else {
+      everything = new Uint8Array();
+    }
+  };
+
+  this.reset = function() {
+    everything = new Uint8Array();
+    this.trigger('reset');
+  };
+
+  this.endTimeline = function() {
+    everything = new Uint8Array();
+    this.trigger('endedtimeline');
+  };
+};
+
+AacStream.prototype = new Stream();
+
+module.exports = AacStream;