int numBlocks = dw.getYSize() / cm.getScanLinesPerBlock();
long blockPtrPos = out.getStreamPosition();
long blockPos = blockPtrPos + 8 * numBlocks;
int maximumBlockSize = computeMaximumTileSize(new V2i(dw.getXSize(),
Math.min(dw.getYSize(), cm.getScanLinesPerBlock())));
byte[] blockData = new byte[maximumBlockSize];
IIOByteBuffer buf = new IIOByteBuffer(null, 0, 0);
ByteBuffer bytes = ByteBuffer.wrap(blockData).order(ByteOrder.LITTLE_ENDIAN);