Arrays.fill(offsets, (short)-1);
        private void readOffsets() throws IOException {        	final int dlen = ph.getDataLength();		    for(short pos = 0; pos < dlen; ) {		    	short tid = ByteConversion.byteToShort(data, pos);		    	offsets[tid] = (short)(pos + 2);		    	pos += ByteConversion.byteToInt(data, pos + 2) + 6;		    }        }