1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 |
x3 x6 x6 x774 x774 x6918 x6918 x774 x774 x6 x3 x3 x230 x230 x7902 x7902 x230 x230 |
const CRC = function (): Uint32Array {
const array = new Uint32Array(256);
for (let i = 0; i < 256; ++i) {
let x = i;
for (let j = 0; j < 8; ++j) {
x = (x & 1) ? 0xEDB88320 ^ (x >>> 1) : x >>> 1;
}
array[i] = x;
}
return array;
}();
export function calcCRC(buffer: Uint8Array | Uint8ClampedArray): number {
let crc = 0xFFFFFFFF;
for (let i = 0; i < buffer.length; ++i) {
crc = CRC[(crc ^ buffer[i]) & 0xFF] ^ (crc >>> 8);
}
return ~crc >>> 0;
}
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