Implement m4a

lib/id3/common.js

@@ -25,3 +25,75 @@ exports.getInt24 = function getInt24 (b, offset, big_endian) {
   if (int < 0) int += 16777216;
   return int;
 };
+
+var decodeString = exports.decodeString = function decodeString(b, charset, start, end) {
+  switch (charset) {
+    case 'ascii':
+      return {
+        text:   b.toString(charset, start, end),
+        length: end - start
+      };
+    case 'utf16':
+      var bytes = getBytes(b, start, end);
+      return {
+        text:   readUTF16String(bytes),
+        length: bytes.length
+      };
+    case 'utf8':
+      var text = b.toString(charset, start, end);
+      return {
+        text:   text,
+        length: Buffer.byteLength(text)
+      };
+  }
+};
+
+var getBytes = function getBytes (b, start, end) {
+  var i = start,
+      a = [];
+
+  while (i <= end) {
+    a.push(b[i]);
+    i++;
+  }
+
+  return a;
+};
+
+var readUTF16String = function readUTF16String (bytes) {
+  var ix      = 0,
+      offset1 = 1,
+      offset2 = 0,
+      maxBytes = Math.min(maxBytes || bytes.length, bytes.length);
+
+  if (bytes[0] === 0xFE && bytes[1] === 0xFF) {
+    bigEndian = true;
+    ix        = 2;
+    offset1   = 0;
+    offset2   = 1;
+  } else if (bytes[0] === 0xFF && bytes[1] === 0xFE) {
+    bigEndian = false;
+    ix = 2;
+  }
+
+  var arr = [];
+  for (var j = 0; ix < maxBytes; j++) {
+    var byte1 = bytes[ix + offset1],
+        byte2 = bytes[ix + offset2],
+        word1 = (byte1 << 8) + byte2;
+    ix += 2;
+
+    if (word1 === 0x0000) {
+      break;
+    } else if (byte1 < 0xD8 || byte1 >= 0xE0) {
+      arr[j] = String.fromCharCode(word1);
+    } else {
+      var byte3 = bytes[ix+offset1],
+          byte4 = bytes[ix+offset2],
+          word2 = (byte3 << 8) + byte4;
+      ix += 2;
+      arr[j] = String.fromCharCode(word1, word2);
+    }
+  }
+  return arr.join('');
+};

lib/id3/id3v2_frames.js

@@ -1,7 +1,8 @@
-var Buffer   = require('buffer').Buffer,
-    strtok   = require('strtok'),
-    common   = require('./common'),
-    findZero = common.findZero;
+var Buffer       = require('buffer').Buffer,
+    strtok       = require('strtok'),
+    common       = require('./common'),
+    findZero     = common.findZero,
+    decodeString = common.decodeString;
 
 exports.readData = function readData (b, type, offset, length, flags, major) {
   major || (major = 3);
@@ -120,28 +121,6 @@ var getTextEncoding = function getTextEncoding (byte) {
   return 'utf8';
 };
 
-var decodeString = function decodeString(b, charset, start, end) {
-  switch (charset) {
-    case 'ascii':
-      return {
-        text:   b.toString(charset, start, end),
-        length: end - start
-      };
-    case 'utf16':
-      var bytes = getBytes(b, start, end);
-      return {
-        text:   readUTF16String(bytes),
-        length: bytes.length
-      };
-    case 'utf8':
-      var text = b.toString(charset, start, end);
-      return {
-        text:   text,
-        length: Buffer.byteLength(text)
-      };
-  }
-};
-
 var PICTURE_TYPE = exports.PICTURE_TYPE = [
   "32x32 pixels 'file icon' (PNG only)",
   "Other file icon",
@@ -164,53 +143,3 @@ var PICTURE_TYPE = exports.PICTURE_TYPE = [
   "Band/artist logotype",
   "Publisher/Studio logotype"
 ];
-
-var getBytes = function getBytes (b, start, end) {
-  var i = start,
-      a = [];
-
-  while (i <= end) {
-    a.push(b[i]);
-    i++;
-  }
-
-  return a;
-};
-
-var readUTF16String = function readUTF16String (bytes) {
-  var ix      = 0,
-      offset1 = 1,
-      offset2 = 0,
-      maxBytes = Math.min(maxBytes || bytes.length, bytes.length);
-
-  if (bytes[0] === 0xFE && bytes[1] === 0xFF) {
-    bigEndian = true;
-    ix        = 2;
-    offset1   = 0;
-    offset2   = 1;
-  } else if (bytes[0] === 0xFF && bytes[1] === 0xFE) {
-    bigEndian = false;
-    ix = 2;
-  }
-
-  var arr = [];
-  for (var j = 0; ix < maxBytes; j++) {
-    var byte1 = bytes[ix + offset1],
-        byte2 = bytes[ix + offset2],
-        word1 = (byte1 << 8) + byte2;
-    ix += 2;
-
-    if (word1 === 0x0000) {
-      break;
-    } else if (byte1 < 0xD8 || byte1 >= 0xE0) {
-      arr[j] = String.fromCharCode(word1);
-    } else {
-      var byte3 = bytes[ix+offset1],
-          byte4 = bytes[ix+offset2],
-          word2 = (byte3 << 8) + byte4;
-      ix += 2;
-      arr[j] = String.fromCharCode(word1, word2);
-    }
-  }
-  return arr.join('');
-};

lib/id3/id4.js

@@ -1,4 +1,101 @@
+var strtok   = require('strtok'),
+    common   = require('./common'),
+    getInt24 = common.getInt24;
 
 exports.readTags = function readTags () {
-  var buffer = this.buffer;
+  var tag = {};
+  readAtom(this.buffer, tag, 0, this.buffer.length);
+  return tag;
+};
+
+var readAtom = function readAtom (b, tag, offset, length, indent) {
+  var seek   = offset,
+      atom_size,
+      atom_name;
+
+  indent = indent === undefined ? '' : indent + '  ';
+
+  while (seek < offset + length) {
+    atom_offset = seek;
+
+    atom_size = strtok.UINT32_BE.get(b, seek);
+    if (atom_size === 0) return;
+
+    if (b[seek + 4] === 169) {
+      atom_name = b.toString('ascii', seek + 5, seek + 5 + 3);
+    } else {
+      atom_name = b.toString('ascii', seek + 4, seek + 4 + 4);
+    }
+
+    if (~CONTAINER_ATOMS.indexOf(atom_name)) {
+      if (atom_name === 'meta') seek += 4;
+      return readAtom(b, tag, seek + 8, atom_size - 8, indent);
+    }
+
+    if (ATOMS[atom_name]) {
+      var klass = getInt24(b, seek + 16 + 1, true),
+          atom  = ATOMS[atom_name],
+          type  = TYPES[klass];
+
+      if (atom_name === 'trkn') {
+        tag[atom[0]] = b[seek + 16 + 11];
+        tag['count'] = b[seek + 16 + 13];
+      } else {
+        var data_start = seek + 16 + 4 + 4,
+            data_end   = atom_size - 16 - 4 - 4;
+
+        switch (type) {
+          case 'text':
+            tag[atom[0]] = b.toString('utf8', data_start, data_start + data_end);
+            break;
+          case 'uint8':
+            tag[atom[0]] = strtok.UINT16_BE.get(b, data_start);
+            break;
+          case 'jpeg':
+          case 'png':
+            tag[atom[0]] = {
+              format: 'image/' + type,
+              data:   b.slice(data_start, data_start + data_end)
+            };
+            break;
+        }
+      }
+    }
+
+    seek += atom_size;
+  }
+};
+
+var TYPES = exports.TYPES = {
+  '0'     : 'uint8',
+  '1'     : 'text',
+  '13'    : 'jpeg',
+  '14'    : 'png',
+  '21'    : 'uint8'
+};
+
+var CONTAINER_ATOMS = exports.CONTAINER_ATOMS = [
+  'moov',
+  'udta',
+  'meta',
+  'ilst'
+];
+
+var ATOMS = exports.ATOMS = {
+  'alb': ['album'],
+  'art': ['artist'],
+  'ART': ['artist'],
+  'aART': ['artist'],
+  'day': ['year'],
+  'nam': ['title'],
+  'gen': ['genre'],
+  'trkn': ['track'],
+  'wrt': ['composer'],
+  'too': ['encoder'],
+  'cprt': ['copyright'],
+  'covr': ['picture'],
+  'grp': ['grouping'],
+  'keyw': ['keyword'],
+  'lyr': ['lyrics'],
+  'gen': ['genre']
 };