| public com.coremedia.iso.boxes.Box | parseBox(java.nio.channels.ReadableByteChannel byteChannel, com.coremedia.iso.boxes.ContainerBox parent)Parses the next size and type, creates a box instance and parses the box's content.
ByteBuffer header = ChannelHelper.readFully(byteChannel, 8);
long size = IsoTypeReader.readUInt32(header);
// do plausibility check
if (size < 8 && size > 1) {
LOG.severe("Plausibility check failed: size < 8 (size = " + size + "). Stop parsing!");
return null;
}
String type = IsoTypeReader.read4cc(header);
//System.err.println(type);
byte[] usertype = null;
long contentSize;
if (size == 1) {
ByteBuffer bb = ByteBuffer.allocate(8);
byteChannel.read(bb);
bb.rewind();
size = IsoTypeReader.readUInt64(bb);
contentSize = size - 16;
} else if (size == 0) {
if (byteChannel instanceof FileChannel) {
size = ((FileChannel) byteChannel).size() - ((FileChannel) byteChannel).position() - 8;
} else {
throw new RuntimeException("Only FileChannel inputs may use size == 0 (box reaches to the end of file)");
}
contentSize = size - 8;
} else {
contentSize = size - 8;
}
if (UserBox.TYPE.equals(type)) {
ByteBuffer bb = ByteBuffer.allocate(16);
byteChannel.read(bb);
bb.rewind();
usertype = bb.array();
contentSize -= 16;
}
Box box = createBox(type, usertype, parent.getType());
box.setParent(parent);
LOG.finest("Parsing " + box.getType());
// System.out.println("parsing " + Arrays.toString(box.getType()) + " " + box.getClass().getName() + " size=" + size);
if (l2i(size - contentSize) == 8) {
// default - no large box - no uuid
// do nothing header's already correct
header.rewind();
} else if (l2i(size - contentSize) == 16) {
header = ByteBuffer.allocate(16);
IsoTypeWriter.writeUInt32(header, 1);
header.put(IsoFile.fourCCtoBytes(type));
IsoTypeWriter.writeUInt64(header, size);
} else if (l2i(size - contentSize) == 24) {
header = ByteBuffer.allocate(24);
IsoTypeWriter.writeUInt32(header, size);
header.put(IsoFile.fourCCtoBytes(type));
header.put(usertype);
} else if (l2i(size - contentSize) == 32) {
header = ByteBuffer.allocate(32);
IsoTypeWriter.writeUInt32(header, size);
header.put(IsoFile.fourCCtoBytes(type));
IsoTypeWriter.writeUInt64(header, size);
header.put(usertype);
} else {
throw new RuntimeException("I didn't expect that");
}
box.parse(byteChannel, header, contentSize, this);
// System.out.println("box = " + box);
assert size == box.getSize() :
"Reconstructed Size is not x to the number of parsed bytes! (" +
box.getType() + ")"
+ " Actual Box size: " + size + " Calculated size: " + box.getSize();
return box;
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