+async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
+ command = command.loop(undefined)
+
+ command = await presetVideo(command, options.audioPath, options)
+
+ command.outputOption('-preset:v veryfast')
+
+ command = command.input(options.audioPath)
+ .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
+ .outputOption('-tune stillimage')
+ .outputOption('-shortest')
+
+ return command
+}
+
+function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
+ command = presetOnlyAudio(command)
+
+ return command
+}
+
+function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
+ command = presetCopy(command)
+
+ command = command.outputOption('-map_metadata -1') // strip all metadata
+ .outputOption('-movflags faststart')
+
+ return command
+}
+
+function addCommonHLSVODCommandOptions (command: ffmpeg.FfmpegCommand, outputPath: string) {
+ return command.outputOption('-hls_time 4')
+ .outputOption('-hls_list_size 0')
+ .outputOption('-hls_playlist_type vod')
+ .outputOption('-hls_segment_filename ' + outputPath)
+ .outputOption('-hls_segment_type fmp4')
+ .outputOption('-f hls')
+ .outputOption('-hls_flags single_file')
+}
+
+async function buildHLSVODCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
+ const videoPath = getHLSVideoPath(options)
+
+ if (options.copyCodecs) command = presetCopy(command)
+ else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
+ else command = await buildx264VODCommand(command, options)
+
+ addCommonHLSVODCommandOptions(command, videoPath)
+
+ return command
+}
+
+async function buildHLSVODFromTSCommand (command: ffmpeg.FfmpegCommand, options: HLSFromTSTranscodeOptions) {
+ const videoPath = getHLSVideoPath(options)
+
+ command.outputOption('-c copy')
+
+ if (options.isAAC) {
+ // Required for example when copying an AAC stream from an MPEG-TS
+ // Since it's a bitstream filter, we don't need to reencode the audio
+ command.outputOption('-bsf:a aac_adtstoasc')
+ }
+
+ addCommonHLSVODCommandOptions(command, videoPath)
+
+ return command
+}
+
+async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
+ if (options.type !== 'hls' && options.type !== 'hls-from-ts') return