123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183 |
- import { toUint8, bytesMatch } from './byte-helpers.js';
- import { findBox } from './mp4-helpers.js';
- import { findEbml, EBML_TAGS } from './ebml-helpers.js';
- import { getId3Offset } from './id3-helpers.js';
- import { findH264Nal, findH265Nal } from './nal-helpers.js';
- var CONSTANTS = {
- // "webm" string literal in hex
- 'webm': toUint8([0x77, 0x65, 0x62, 0x6d]),
- // "matroska" string literal in hex
- 'matroska': toUint8([0x6d, 0x61, 0x74, 0x72, 0x6f, 0x73, 0x6b, 0x61]),
- // "fLaC" string literal in hex
- 'flac': toUint8([0x66, 0x4c, 0x61, 0x43]),
- // "OggS" string literal in hex
- 'ogg': toUint8([0x4f, 0x67, 0x67, 0x53]),
- // ac-3 sync byte, also works for ec-3 as that is simply a codec
- // of ac-3
- 'ac3': toUint8([0x0b, 0x77]),
- // "RIFF" string literal in hex used for wav and avi
- 'riff': toUint8([0x52, 0x49, 0x46, 0x46]),
- // "AVI" string literal in hex
- 'avi': toUint8([0x41, 0x56, 0x49]),
- // "WAVE" string literal in hex
- 'wav': toUint8([0x57, 0x41, 0x56, 0x45]),
- // "ftyp3g" string literal in hex
- '3gp': toUint8([0x66, 0x74, 0x79, 0x70, 0x33, 0x67]),
- // "ftyp" string literal in hex
- 'mp4': toUint8([0x66, 0x74, 0x79, 0x70]),
- // "styp" string literal in hex
- 'fmp4': toUint8([0x73, 0x74, 0x79, 0x70]),
- // "ftypqt" string literal in hex
- 'mov': toUint8([0x66, 0x74, 0x79, 0x70, 0x71, 0x74]),
- // moov string literal in hex
- 'moov': toUint8([0x6D, 0x6F, 0x6F, 0x76]),
- // moof string literal in hex
- 'moof': toUint8([0x6D, 0x6F, 0x6F, 0x66])
- };
- var _isLikely = {
- aac: function aac(bytes) {
- var offset = getId3Offset(bytes);
- return bytesMatch(bytes, [0xFF, 0x10], {
- offset: offset,
- mask: [0xFF, 0x16]
- });
- },
- mp3: function mp3(bytes) {
- var offset = getId3Offset(bytes);
- return bytesMatch(bytes, [0xFF, 0x02], {
- offset: offset,
- mask: [0xFF, 0x06]
- });
- },
- webm: function webm(bytes) {
- var docType = findEbml(bytes, [EBML_TAGS.EBML, EBML_TAGS.DocType])[0]; // check if DocType EBML tag is webm
- return bytesMatch(docType, CONSTANTS.webm);
- },
- mkv: function mkv(bytes) {
- var docType = findEbml(bytes, [EBML_TAGS.EBML, EBML_TAGS.DocType])[0]; // check if DocType EBML tag is matroska
- return bytesMatch(docType, CONSTANTS.matroska);
- },
- mp4: function mp4(bytes) {
- // if this file is another base media file format, it is not mp4
- if (_isLikely['3gp'](bytes) || _isLikely.mov(bytes)) {
- return false;
- } // if this file starts with a ftyp or styp box its mp4
- if (bytesMatch(bytes, CONSTANTS.mp4, {
- offset: 4
- }) || bytesMatch(bytes, CONSTANTS.fmp4, {
- offset: 4
- })) {
- return true;
- } // if this file starts with a moof/moov box its mp4
- if (bytesMatch(bytes, CONSTANTS.moof, {
- offset: 4
- }) || bytesMatch(bytes, CONSTANTS.moov, {
- offset: 4
- })) {
- return true;
- }
- },
- mov: function mov(bytes) {
- return bytesMatch(bytes, CONSTANTS.mov, {
- offset: 4
- });
- },
- '3gp': function gp(bytes) {
- return bytesMatch(bytes, CONSTANTS['3gp'], {
- offset: 4
- });
- },
- ac3: function ac3(bytes) {
- var offset = getId3Offset(bytes);
- return bytesMatch(bytes, CONSTANTS.ac3, {
- offset: offset
- });
- },
- ts: function ts(bytes) {
- if (bytes.length < 189 && bytes.length >= 1) {
- return bytes[0] === 0x47;
- }
- var i = 0; // check the first 376 bytes for two matching sync bytes
- while (i + 188 < bytes.length && i < 188) {
- if (bytes[i] === 0x47 && bytes[i + 188] === 0x47) {
- return true;
- }
- i += 1;
- }
- return false;
- },
- flac: function flac(bytes) {
- var offset = getId3Offset(bytes);
- return bytesMatch(bytes, CONSTANTS.flac, {
- offset: offset
- });
- },
- ogg: function ogg(bytes) {
- return bytesMatch(bytes, CONSTANTS.ogg);
- },
- avi: function avi(bytes) {
- return bytesMatch(bytes, CONSTANTS.riff) && bytesMatch(bytes, CONSTANTS.avi, {
- offset: 8
- });
- },
- wav: function wav(bytes) {
- return bytesMatch(bytes, CONSTANTS.riff) && bytesMatch(bytes, CONSTANTS.wav, {
- offset: 8
- });
- },
- 'h264': function h264(bytes) {
- // find seq_parameter_set_rbsp
- return findH264Nal(bytes, 7, 3).length;
- },
- 'h265': function h265(bytes) {
- // find video_parameter_set_rbsp or seq_parameter_set_rbsp
- return findH265Nal(bytes, [32, 33], 3).length;
- }
- }; // get all the isLikely functions
- // but make sure 'ts' is above h264 and h265
- // but below everything else as it is the least specific
- var isLikelyTypes = Object.keys(_isLikely) // remove ts, h264, h265
- .filter(function (t) {
- return t !== 'ts' && t !== 'h264' && t !== 'h265';
- }) // add it back to the bottom
- .concat(['ts', 'h264', 'h265']); // make sure we are dealing with uint8 data.
- isLikelyTypes.forEach(function (type) {
- var isLikelyFn = _isLikely[type];
- _isLikely[type] = function (bytes) {
- return isLikelyFn(toUint8(bytes));
- };
- }); // export after wrapping
- export var isLikely = _isLikely; // A useful list of file signatures can be found here
- // https://en.wikipedia.org/wiki/List_of_file_signatures
- export var detectContainerForBytes = function detectContainerForBytes(bytes) {
- bytes = toUint8(bytes);
- for (var i = 0; i < isLikelyTypes.length; i++) {
- var type = isLikelyTypes[i];
- if (isLikely[type](bytes)) {
- return type;
- }
- }
- return '';
- }; // fmp4 is not a container
- export var isLikelyFmp4MediaSegment = function isLikelyFmp4MediaSegment(bytes) {
- return findBox(bytes, ['moof']).length > 0;
- };
|