Exemple #1
0
 /**
  * Decode an array of 4 bit element IDs, optionally interleaved with a stereo/mono switching bit.
  *
  * @throws IOException
  */
 private void decodeChannelMap(
     ChannelMapping layout_map[], int offset, ChannelPosition type, InBits in, int n)
     throws IOException {
   while (n-- > 0) {
     RawDataBlockType syn_ele = null;
     switch (type) {
       case AAC_CHANNEL_FRONT:
       case AAC_CHANNEL_BACK:
       case AAC_CHANNEL_SIDE:
         syn_ele = RawDataBlockType.fromOrdinal(in.read1Bit());
         break;
       case AAC_CHANNEL_CC:
         in.read1Bit();
         syn_ele = RawDataBlockType.TYPE_CCE;
         break;
       case AAC_CHANNEL_LFE:
         syn_ele = RawDataBlockType.TYPE_LFE;
         break;
     }
     layout_map[offset].syn_ele = syn_ele;
     layout_map[offset].someInt = (int) in.readNBit(4);
     layout_map[offset].position = type;
     offset++;
   }
 }
Exemple #2
0
  public void parse(InBits in) throws IOException {

    in.readNBit(2); // object_type

    int samplingIndex = (int) in.readNBit(4);

    int num_front = (int) in.readNBit(4);
    int num_side = (int) in.readNBit(4);
    int num_back = (int) in.readNBit(4);
    int num_lfe = (int) in.readNBit(2);
    int num_assoc_data = (int) in.readNBit(3);
    int num_cc = (int) in.readNBit(4);

    if (in.read1Bit() != 0) in.readNBit(4); // mono_mixdown_tag
    if (in.read1Bit() != 0) in.readNBit(4); // stereo_mixdown_tag

    if (in.read1Bit() != 0) in.readNBit(3); // mixdown_coeff_index and pseudo_surround

    //        if (!in.moreData(4 * (num_front + num_side + num_back + num_lfe + num_assoc_data +
    // num_cc))) {
    //            throw new RuntimeException("Overread");
    //        }
    ChannelMapping[] layout_map = new ChannelMapping[MAX_ELEM_ID * 4];

    int tags = 0;
    decodeChannelMap(layout_map, tags, ChannelPosition.AAC_CHANNEL_FRONT, in, num_front);
    tags = num_front;
    decodeChannelMap(layout_map, tags, ChannelPosition.AAC_CHANNEL_SIDE, in, num_side);
    tags += num_side;
    decodeChannelMap(layout_map, tags, ChannelPosition.AAC_CHANNEL_BACK, in, num_back);
    tags += num_back;
    decodeChannelMap(layout_map, tags, ChannelPosition.AAC_CHANNEL_LFE, in, num_lfe);
    tags += num_lfe;

    in.skip(4 * num_assoc_data);

    decodeChannelMap(layout_map, tags, ChannelPosition.AAC_CHANNEL_CC, in, num_cc);
    tags += num_cc;

    in.align();

    /* comment field, first byte is length */
    int comment_len = (int) in.readNBit(8) * 8;
    //        if (!in.moreData(comment_len)) {
    //            throw new RuntimeException("Overread");
    //        }
    in.skip(comment_len);
  }