dist/irisLib.js
function crc32(png, offs, size) {
					var crc = -1;
					for (var i = 4; i < size-4; i += 1) {
						crc = _crc32[(crc ^ png[offs+i].charCodeAt(0)) & 0xff] ^ ((crc >> 8) & 0x00ffffff);
					}
					write(png, offs+size-4, byte4(crc ^ -1));
				}
function crc32(png, offs, size) {
					var crc = -1;
					for (var i = 4; i < size-4; i += 1) {
						crc = _crc32[(crc ^ png[offs+i].charCodeAt(0)) & 0xff] ^ ((crc >> 8) & 0x00ffffff);
					}
					write(png, offs+size-4, byte4(crc ^ -1));
				}
function crc32 ( png , offs , size ) { var crc = - 1 ; for ( var i = 4 ; i < size - 4 ; i += 1 ) { crc = _crc32 [ ( crc ^ png [ offs + i ] . charCodeAt ( 0 ) ) & 0xff ] ^ ( ( crc >> 8 ) & 0x00ffffff ) ; } write ( png , offs + size - 4 , byte4 ( crc ^ - 1 ) ) ; }
compute crc32 of the PNG chunks
compute crc32 of the PNG chunks