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added hevc decoder configuration parser
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@fogarasyroland @robwalch
fogarasyroland authored and robwalch committed May 31, 2023
1 parent a94f703 commit 890fae3
Showing 1 changed file with 178 additions and 35 deletions.
213 changes: 178 additions & 35 deletions src/utils/mp4-tools.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -67,7 +67,6 @@ export function findBox(data: Uint8Array, path: string[]): Uint8Array[] {
const size = readUint32(data, i);
const type = bin2str(data.subarray(i + 4, i + 8));
const endbox = size > 1 ? i + size : end;

if (type === path[0]) {
if (path.length === 1) {
// this is the end of the path and we've found the box we were
Expand Down Expand Up @@ -264,44 +263,61 @@ export function parseInitSegment(initSegment: Uint8Array): InitData {
}

// Handle H265
else if (
(codec === 'hev1' || codec === 'hvc1') &&
stsd.length > 102 &&
bin2str(stsd.subarray(98, 102)) === 'hvcC'
) {
// Profile Space
const profileByte = stsd[103];
const profileSpace = { 0: '', 1: 'A', 2: 'B', 3: 'C' }[
profileByte >> 6
];
const generalProfileIdc = profileByte & 31;
codec += '.' + profileSpace + generalProfileIdc;

// Compatibility
let reversed = 0;
for (let i = 0; i < 4; ++i) {
// byte number
for (let j = 0; j < 8; ++j) {
// bit number
reversed |=
((stsd[i + 104] >> (7 - j)) & 1) << (31 - 8 * i - j);
else if (isHEVC(codec)) {
// @fogarasyroland's method https://github.com/video-dev/hls.js/pull/5024
let hvcC;
const codecBox = findBox(stsd.subarray(8), [codec])[0];
if (codecBox) {
const { end } = parseVisualSampleEntry(codecBox);
hvcC = findBox(codecBox.subarray(end), ['hvcC'])[0];
if (hvcC) {
codec = mimeTypeBuilderHEVC(
codec,
parseHvcConfigurationRecord(hvcC)
);
}
}
codec += '.' + toHex(reversed >>> 0);

// Tier Flag
codec += (profileByte & 32 ? '.H' : '.L') + stsd[114];

// Constraint String
let hasByte = false;
let constraintString = '';
for (let i = 113; i > 107; --i) {
if (stsd[i] || hasByte) {
constraintString = '.' + toHex(stsd[i]) + constraintString;
hasByte = true;
// @uvjustin's method https://github.com/video-dev/hls.js/pull/4996
if (
!hvcC &&
stsd.length > 102 &&
bin2str(stsd.subarray(98, 102)) === 'hvcC'
) {
// Profile Space
const profileByte = stsd[103];
const profileSpace = { 0: '', 1: 'A', 2: 'B', 3: 'C' }[
profileByte >> 6
];
const generalProfileIdc = profileByte & 31;
codec += '.' + profileSpace + generalProfileIdc;

// Compatibility
let reversed = 0;
for (let i = 0; i < 4; ++i) {
// byte number
for (let j = 0; j < 8; ++j) {
// bit number
reversed |=
((stsd[i + 104] >> (7 - j)) & 1) << (31 - 8 * i - j);
}
}
codec += '.' + toHex(reversed >>> 0);

// Tier Flag
codec += (profileByte & 32 ? '.H' : '.L') + stsd[114];

// Constraint String
let hasByte = false;
let constraintString = '';
for (let i = 113; i > 107; --i) {
if (stsd[i] || hasByte) {
constraintString =
'.' + toHex(stsd[i]) + constraintString;
hasByte = true;
}
}
codec += constraintString;
}
codec += constraintString;
}

// Handle Audio
Expand Down Expand Up @@ -1245,3 +1261,130 @@ export function parsePssh(initData: ArrayBuffer) {
}
return result;
}

function mimeTypeBuilderHEVC(
codecName: string,
codecDetails: hvcConfigurationRecord
): string {
const generalProfileSpaceMap = ['', 'A', 'B', 'C'];
let codecMimeType = codecName;
if (codecDetails) {
codecMimeType += '.';
codecMimeType += generalProfileSpaceMap[codecDetails.generalProfileSpace];
codecMimeType += codecDetails.generalProfileIdc;

codecMimeType += '.';
codecMimeType += codecDetails.generalProfileCompatibility.toString(16)[0];

codecMimeType += '.';
codecMimeType += codecDetails.generalTierFlag === 0 ? 'L' : 'H';
codecMimeType += codecDetails.generalLevelIdc;

let constraintString = '';
const lastByteIndex = (
codecDetails.generalConstraintIndicator as any
).findLastIndex((x: Number) => x !== 0);
if (lastByteIndex !== -1) {
constraintString =
'.' +
(
codecDetails.generalConstraintIndicator.slice(
0,
lastByteIndex + 1
) as any
)
.map((x: Number) => x.toString(16))
.join('.');
}

codecMimeType += constraintString;
}
return codecMimeType;
}

function parseDataReferenceIndex(data: Uint8Array) {
// UInt8[6] reserved
return readUint16(data, 6);
}

interface visualSampleEntry {
dataReferenceIndex: number;
width: number;
height: number;
horizResolution: number;
vertResolution: number;
frameCount: number;
compressorName: string;
depth: number;
end: number;
}

function parseVisualSampleEntry(data: Uint8Array): visualSampleEntry {
return {
dataReferenceIndex: parseDataReferenceIndex(data),

// UInt16 preDefined
// UInt16 reserved
// UInt32[3] preDefined

width: readUint16(data, 24),
height: readUint16(data, 26),

horizResolution: readUint32(data, 28), // 0x00480000 - 72 dpi
vertResolution: readUint32(data, 32), // 0x00480000 - 72 dpi

// UInt32 reserved

frameCount: readUint16(data, 40),
compressorName: bin2str(data.subarray(43, Math.min(data[42], 31))),
depth: readUint16(data, 74),

// UInt16 preDefined

end: 78,
};
}

interface hvcConfigurationRecord {
configurationVersion: number;
generalProfileSpace: number;
generalTierFlag: number;
generalProfileIdc: number;
generalProfileCompatibility: number;
generalConstraintIndicator: Uint8Array;
generalLevelIdc: number;
minSpatialSegmentationIdc: number;
parallelismType: number;
chromaFormatIdc: number;
bitDepthLumaMinus8: number;
bitDepthChromaMinus8: number;
avgFrameRate: number;
constantFrameRate: number;
numTemporalLayers: number;
temporalIdNested: number;
lengthSizeMinusOne: number;
naluArrays: Array<object>;
}

function parseHvcConfigurationRecord(data: Uint8Array): hvcConfigurationRecord {
return {
configurationVersion: data[0],
generalProfileSpace: data[1] >> 6,
generalTierFlag: (data[1] & 0x20) >> 5,
generalProfileIdc: data[1] & 0x1f,
generalProfileCompatibility: readUint32(data, 2),
generalConstraintIndicator: data.subarray(6, 12),
generalLevelIdc: data[12],
minSpatialSegmentationIdc: readUint16(data, 13) & 0xfff,
parallelismType: data[15] & 0x3,
chromaFormatIdc: data[16] & 0x3,
bitDepthLumaMinus8: data[17] & 0x7,
bitDepthChromaMinus8: data[18] & 0x7,
avgFrameRate: readUint16(data, 19),
constantFrameRate: data[21] >> 6,
numTemporalLayers: (data[21] & 0xd) >> 3,
temporalIdNested: (data[21] & 0x4) >> 2,
lengthSizeMinusOne: data[21] & 0x3,
naluArrays: [],
};
}

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