Exemplo n.º 1
0
  private void setHeader() {
    // create the atoms needed to build the header.
    Atom a_ftyp = getFTYPAtom();
    Atom a_moov = getMOOVAtom();
    Atom a_mdat = new Atom("mdat"); // create an empty atom. The AAC stream data should follow
    // immediately after. The correct size will be set later.

    // set the correct chunk offset in the stco atom.
    Atom a_stco = a_moov.getChild("trak.mdia.minf.stbl.stco");
    if (a_stco == null) {
      mHeader = null;
      return;
    }
    byte[] data = a_stco.getData();
    int chunk_offset = a_ftyp.getSize() + a_moov.getSize() + a_mdat.getSize();
    int offset = data.length - 4; // here stco should contain only one chunk offset.
    data[offset++] = (byte) ((chunk_offset >> 24) & 0xFF);
    data[offset++] = (byte) ((chunk_offset >> 16) & 0xFF);
    data[offset++] = (byte) ((chunk_offset >> 8) & 0xFF);
    data[offset++] = (byte) (chunk_offset & 0xFF);

    // create the header byte array based on the previous atoms.
    byte[] header = new byte[chunk_offset]; // here chunk_offset is also the size of the header
    offset = 0;
    for (Atom atom : new Atom[] {a_ftyp, a_moov, a_mdat}) {
      byte[] atom_bytes = atom.getBytes();
      System.arraycopy(atom_bytes, 0, header, offset, atom_bytes.length);
      offset += atom_bytes.length;
    }

    // set the correct size of the mdat atom
    int size = 8 + mTotSize;
    offset -= 8;
    header[offset++] = (byte) ((size >> 24) & 0xFF);
    header[offset++] = (byte) ((size >> 16) & 0xFF);
    header[offset++] = (byte) ((size >> 8) & 0xFF);
    header[offset++] = (byte) (size & 0xFF);

    mHeader = header;
  }
Exemplo n.º 2
0
 // set the size field of the atom based on its content.
 private void setSize() {
   int size = 8; // type + size
   if (mVersion >= 0) {
     size += 4; // version + flags
   }
   if (mData != null) {
     size += mData.length;
   } else if (mChildren != null) {
     for (Atom child : mChildren) {
       size += child.getSize();
     }
   }
   mSize = size;
 }