public void checkCrc() {
int crcComputed = (int) crcengine.getValue();
int crcExpected = PngHelperInternal.readInt4fromBytes(crcval, 0);
if (crcComputed != crcExpected)
throw new PngjBadCrcException("chunk: " + this.toString() + " expected=" + crcExpected
+ " read=" + crcComputed);
}