@gmod/cram
Version:
read CRAM files with pure Javascript
68 lines • 2.79 kB
JavaScript
// @ts-nocheck
import { CramMalformedError } from "../errors.js";
import { TF_SHIFT } from "./constants.js";
import Decoding from "./decoding.js";
export default function uncompress(
/* ByteBuffer */ input,
/* Decoding.AriDecoder */ D,
/* Decoding.Symbol[] */ syms,
/* ByteBuffer */ out) {
let rans0 = input.getInt();
let rans1 = input.getInt();
let rans2 = input.getInt();
let rans3 = input.getInt();
const /* int */ outputSize = out.remaining();
const /* int */ outputEnd = outputSize & ~3;
for (let i = 0; i < outputEnd; i += 4) {
const /* byte */ c0 = D.R[Decoding.get(rans0, TF_SHIFT)];
const /* byte */ c1 = D.R[Decoding.get(rans1, TF_SHIFT)];
const /* byte */ c2 = D.R[Decoding.get(rans2, TF_SHIFT)];
const /* byte */ c3 = D.R[Decoding.get(rans3, TF_SHIFT)];
out.putAt(i, c0);
out.putAt(i + 1, c1);
out.putAt(i + 2, c2);
out.putAt(i + 3, c3);
rans0 = Decoding.advanceSymbolStep(rans0, syms[0xff & c0], TF_SHIFT);
rans1 = Decoding.advanceSymbolStep(rans1, syms[0xff & c1], TF_SHIFT);
rans2 = Decoding.advanceSymbolStep(rans2, syms[0xff & c2], TF_SHIFT);
rans3 = Decoding.advanceSymbolStep(rans3, syms[0xff & c3], TF_SHIFT);
rans0 = Decoding.renormalize(rans0, input);
rans1 = Decoding.renormalize(rans1, input);
rans2 = Decoding.renormalize(rans2, input);
rans3 = Decoding.renormalize(rans3, input);
}
out.setPosition(outputEnd);
let /* byte */ c;
switch (outputSize & 3) {
case 0:
break;
case 1:
c = D.R[Decoding.get(rans0, TF_SHIFT)];
Decoding.advanceSymbol(rans0, input, syms[0xff & c], TF_SHIFT);
out.put(c);
break;
case 2:
c = D.R[Decoding.get(rans0, TF_SHIFT)];
Decoding.advanceSymbol(rans0, input, syms[0xff & c], TF_SHIFT);
out.put(c);
c = D.R[Decoding.get(rans1, TF_SHIFT)];
Decoding.advanceSymbol(rans1, input, syms[0xff & c], TF_SHIFT);
out.put(c);
break;
case 3:
c = D.R[Decoding.get(rans0, TF_SHIFT)];
Decoding.advanceSymbol(rans0, input, syms[0xff & c], TF_SHIFT);
out.put(c);
c = D.R[Decoding.get(rans1, TF_SHIFT)];
Decoding.advanceSymbol(rans1, input, syms[0xff & c], TF_SHIFT);
out.put(c);
c = D.R[Decoding.get(rans2, TF_SHIFT)];
Decoding.advanceSymbol(rans2, input, syms[0xff & c], TF_SHIFT);
out.put(c);
break;
default:
throw new CramMalformedError('invalid output size encountered during rANS decoding');
}
out.setPosition(0);
}
//# sourceMappingURL=d04.js.map