Adolfo Reyna
48 lines
2.0 KiB
JavaScript
48 lines
2.0 KiB
JavaScript
"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.getHvc1CodecString = void 0;
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const getHvc1CodecString = (data) => {
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const configurationVersion = data.getUint8();
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if (configurationVersion !== 1) {
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throw new Error(`Unsupported HVCC version ${configurationVersion}`);
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}
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const generalProfileSpaceTierFlagAndIdc = data.getUint8();
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let generalProfileCompatibility = data.getUint32();
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// unsigned int(2) general_profile_space;
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// unsigned int(1) general_tier_flag;
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// unsigned int(5) general_profile_idc;
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const generalProfileSpace = generalProfileSpaceTierFlagAndIdc >> 6;
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const generalTierFlag = (generalProfileSpaceTierFlagAndIdc & 0x20) >> 5;
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const generalProfileIdc = generalProfileSpaceTierFlagAndIdc & 0x1f;
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// general_constraint_indicator_flags(48)
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const generalConstraintIndicator = data.getSlice(6);
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const generalLevelIdc = data.getUint8();
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let profileId = 0;
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for (let i = 0; i < 32; i++) {
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profileId |= generalProfileCompatibility & 1;
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if (i === 31)
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break;
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profileId <<= 1;
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generalProfileCompatibility >>= 1;
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}
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const profileSpaceChar = generalProfileSpace === 0
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? ''
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: generalProfileSpace === 1
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? 'A'
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: generalProfileSpace === 2
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? 'B'
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: 'C';
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const generalTierChar = generalTierFlag === 0 ? 'L' : 'H';
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let hasByte = false;
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let generalConstraintString = '';
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for (let i = 5; i >= 0; i--) {
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if (generalConstraintIndicator[i] || hasByte) {
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generalConstraintString =
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generalConstraintIndicator[i].toString(16) + generalConstraintString;
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hasByte = true;
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}
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}
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return `${profileSpaceChar}${generalProfileIdc.toString(16)}.${profileId.toString(16)}.${generalTierChar}${generalLevelIdc}${generalConstraintString ? '.' : ''}${generalConstraintString}`;
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};
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exports.getHvc1CodecString = getHvc1CodecString;
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