61 lines
1.7 KiB
JavaScript
61 lines
1.7 KiB
JavaScript
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"use strict";
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/**
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* mux.js
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*
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* Copyright (c) Brightcove
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* Licensed Apache-2.0 https://github.com/videojs/mux.js/blob/master/LICENSE
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*/
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var ONE_SECOND_IN_TS = 90000,
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// 90kHz clock
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secondsToVideoTs,
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secondsToAudioTs,
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videoTsToSeconds,
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audioTsToSeconds,
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audioTsToVideoTs,
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videoTsToAudioTs,
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metadataTsToSeconds;
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secondsToVideoTs = function secondsToVideoTs(seconds) {
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return seconds * ONE_SECOND_IN_TS;
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};
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secondsToAudioTs = function secondsToAudioTs(seconds, sampleRate) {
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return seconds * sampleRate;
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};
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videoTsToSeconds = function videoTsToSeconds(timestamp) {
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return timestamp / ONE_SECOND_IN_TS;
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};
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audioTsToSeconds = function audioTsToSeconds(timestamp, sampleRate) {
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return timestamp / sampleRate;
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};
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audioTsToVideoTs = function audioTsToVideoTs(timestamp, sampleRate) {
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return secondsToVideoTs(audioTsToSeconds(timestamp, sampleRate));
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};
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videoTsToAudioTs = function videoTsToAudioTs(timestamp, sampleRate) {
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return secondsToAudioTs(videoTsToSeconds(timestamp), sampleRate);
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};
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/**
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* Adjust ID3 tag or caption timing information by the timeline pts values
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* (if keepOriginalTimestamps is false) and convert to seconds
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*/
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metadataTsToSeconds = function metadataTsToSeconds(timestamp, timelineStartPts, keepOriginalTimestamps) {
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return videoTsToSeconds(keepOriginalTimestamps ? timestamp : timestamp - timelineStartPts);
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};
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module.exports = {
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ONE_SECOND_IN_TS: ONE_SECOND_IN_TS,
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secondsToVideoTs: secondsToVideoTs,
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secondsToAudioTs: secondsToAudioTs,
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videoTsToSeconds: videoTsToSeconds,
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audioTsToSeconds: audioTsToSeconds,
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audioTsToVideoTs: audioTsToVideoTs,
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videoTsToAudioTs: videoTsToAudioTs,
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metadataTsToSeconds: metadataTsToSeconds
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};
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