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