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rx-player

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"use strict"; var __values = (this && this.__values) || function(o) { var s = typeof Symbol === "function" && Symbol.iterator, m = s && o[s], i = 0; if (m) return m.call(o); if (o && typeof o.length === "number") return { next: function () { if (o && i >= o.length) o = void 0; return { value: o && o[i++], done: !o }; } }; throw new TypeError(s ? "Object is not iterable." : "Symbol.iterator is not defined."); }; Object.defineProperty(exports, "__esModule", { value: true }); exports.default = parseMp4EmbeddedWebVtt; var log_1 = require("../../../log"); var byte_parsing_1 = require("../../../utils/byte_parsing"); var string_parsing_1 = require("../../../utils/string_parsing"); var isobmff_1 = require("../../containers/isobmff"); var utils_1 = require("../../containers/isobmff/utils"); var parse_cue_block_1 = require("./parse_cue_block"); /** * WebVTT embedded in an MP4 file weirdly follow another format. * This function attempts to parse it. * @param {BufferSource|string} buffer * @param {number} timescale * @param {number} timeOffset * @param {Function} cueProducer * @returns {Array.<Object>} */ function parseMp4EmbeddedWebVtt(buffer, timescale, timeOffset, cueProducer) { var e_1, _a; var _b, _c; var cuesArray = []; var trackDecodeTime = (0, isobmff_1.getTrackFragmentDecodeTime)(buffer); if (trackDecodeTime === undefined) { return []; } var trunSamples = (0, utils_1.getTrunSamples)(buffer); var mdat = (0, isobmff_1.getMDAT)(buffer); if (mdat === null) { return []; } var mdatOffset = 0; var lastTime = trackDecodeTime; try { for (var trunSamples_1 = __values(trunSamples), trunSamples_1_1 = trunSamples_1.next(); !trunSamples_1_1.done; trunSamples_1_1 = trunSamples_1.next()) { var sample = trunSamples_1_1.value; var duration = (_b = sample.duration) !== null && _b !== void 0 ? _b : 0; var startTime = sample.compositionTimeOffset !== undefined ? lastTime + sample.compositionTimeOffset : lastTime; lastTime = startTime + duration; // Read samples until it adds up to the given size. var totalSize = 0; // No sample size == a single sample while (totalSize < ((_c = sample.size) !== null && _c !== void 0 ? _c : 0)) { // Read the payload size. var payloadSize = (0, byte_parsing_1.be4toi)(mdat, mdatOffset); mdatOffset += 4; totalSize += payloadSize; var currentBoxName = (0, string_parsing_1.utf8ToStr)(mdat.slice(mdatOffset, mdatOffset + 4)); mdatOffset += 4; var currentBoxData = null; if (currentBoxName === "vttc") { if (payloadSize > 8) { currentBoxData = mdat.slice(mdatOffset, mdatOffset + (payloadSize - 8)); mdatOffset += payloadSize - 8; } } else if (currentBoxName === "vtte") { if (payloadSize > 8) { mdatOffset += payloadSize - 8; } } else { log_1.default.error("vtt", "encountered unknown fragmented vtt box", { box: currentBoxName, }); mdatOffset += Math.min(payloadSize - 8, 1); } if (duration > 0) { if (currentBoxData !== null) { var cue = parseVttC(currentBoxData, timeOffset + startTime / timescale, timeOffset + lastTime / timescale, cueProducer); if (cue !== null) { cuesArray.push(cue); } } } else { log_1.default.error("vtt", "cue duration missing"); } } } } catch (e_1_1) { e_1 = { error: e_1_1 }; } finally { try { if (trunSamples_1_1 && !trunSamples_1_1.done && (_a = trunSamples_1.return)) _a.call(trunSamples_1); } finally { if (e_1) throw e_1.error; } } if (mdatOffset !== mdat.length) { log_1.default.error("vtt", "end offset is not equal to mdat length", { mdataOffset: mdatOffset, mdatLength: mdat.length, }); } return cuesArray; } /** * Parse VTT cue data as found in an "vttc" mp4 box. * @param {Uint8Array} data * @param {number} startTime * @param {number} endTime * @returns {Object|null} */ function parseVttC(data, startTime, endTime, cueProducer) { var payload = getPayl(data); var settings = getSttg(data); if (payload === null) { return null; } var cue = cueProducer({ start: startTime, end: endTime, settings: settings !== null ? (0, parse_cue_block_1.parseSettings)((0, string_parsing_1.utf8ToStr)(settings)) : {}, header: undefined, payload: [(0, string_parsing_1.utf8ToStr)(payload)], }, { classes: {}, global: undefined, }); return cue; } /** * Returns the content of the first "payl" box encountered in the given ISOBMFF * data. * Returns null if not found. * @param {Uint8Array} buf * @returns {Uint8Array|null} */ function getPayl(buf) { return (0, isobmff_1.getBoxContent)(buf, 0x7061796c /* "payl" */); } /** * Returns the content of the first "sttg" box encountered in the given ISOBMFF * data. * Returns null if not found. * @param {Uint8Array} buf * @returns {Uint8Array|null} */ function getSttg(buf) { return (0, isobmff_1.getBoxContent)(buf, 0x73747467 /* "sttg" */); }