"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.applyPredictor = void 0; function decodeRowAcc(row, stride) { let length = row.length - stride; let offset = 0; do { for (let i = stride; i > 0; i--) { row[offset + stride] += row[offset]; offset++; } length -= stride; } while (length > 0); } function decodeRowFloatingPoint(row, stride, bytesPerSample) { let index = 0; let count = row.length; const wc = count / bytesPerSample; while (count > stride) { for (let i = stride; i > 0; --i) { row[index + stride] += row[index]; ++index; } count -= stride; } const copy = row.slice(); for (let i = 0; i < wc; ++i) { for (let b = 0; b < bytesPerSample; ++b) { row[(bytesPerSample * i) + b] = copy[((bytesPerSample - b - 1) * wc) + i]; } } } function applyPredictor(block, predictor, width, height, bitsPerSample, planarConfiguration) { if (!predictor || predictor === 1) { return block; } for (let i = 0; i < bitsPerSample.length; ++i) { if (bitsPerSample[i] % 8 !== 0) { throw new Error('When decoding with predictor, only multiple of 8 bits are supported.'); } if (bitsPerSample[i] !== bitsPerSample[0]) { throw new Error('When decoding with predictor, all samples must have the same size.'); } } const bytesPerSample = bitsPerSample[0] / 8; const stride = planarConfiguration === 2 ? 1 : bitsPerSample.length; for (let i = 0; i < height; ++i) { // Last strip will be truncated if height % stripHeight != 0 if (i * stride * width * bytesPerSample >= block.byteLength) { break; } let row; if (predictor === 2) { // horizontal prediction switch (bitsPerSample[0]) { case 8: row = new Uint8Array(block, i * stride * width * bytesPerSample, stride * width * bytesPerSample); break; case 16: row = new Uint16Array(block, i * stride * width * bytesPerSample, stride * width * bytesPerSample / 2); break; case 32: row = new Uint32Array(block, i * stride * width * bytesPerSample, stride * width * bytesPerSample / 4); break; default: throw new Error(`Predictor 2 not allowed with ${bitsPerSample[0]} bits per sample.`); } decodeRowAcc(row, stride, bytesPerSample); } else if (predictor === 3) { // horizontal floating point row = new Uint8Array(block, i * stride * width * bytesPerSample, stride * width * bytesPerSample); decodeRowFloatingPoint(row, stride, bytesPerSample); } } return block; } exports.applyPredictor = applyPredictor; //# sourceMappingURL=predictor.js.map