server/helpers/ffmpeg/ffmpeg-vod.ts

   1 import { Job } from 'bull'
   2 import { FfmpegCommand } from 'fluent-ffmpeg'
   3 import { readFile, writeFile } from 'fs-extra'
   4 import { dirname } from 'path'
   5 import { pick } from '@shared/core-utils'
   6 import { AvailableEncoders, VideoResolution } from '@shared/models'
   7 import { logger, loggerTagsFactory } from '../logger'
   8 import { getFFmpeg, runCommand } from './ffmpeg-commons'
   9 import { presetCopy, presetOnlyAudio, presetVOD } from './ffmpeg-presets'
  10 import { computeFPS, getVideoStreamFPS } from './ffprobe-utils'
  11 import { VIDEO_TRANSCODING_FPS } from '@server/initializers/constants'
  12
  13 const lTags = loggerTagsFactory('ffmpeg')
  14
  15 // ---------------------------------------------------------------------------
  16
  17 type TranscodeVODOptionsType = 'hls' | 'hls-from-ts' | 'quick-transcode' | 'video' | 'merge-audio' | 'only-audio'
  18
  19 interface BaseTranscodeVODOptions {
  20   type: TranscodeVODOptionsType
  21
  22   inputPath: string
  23   outputPath: string
  24
  25   availableEncoders: AvailableEncoders
  26   profile: string
  27
  28   resolution: number
  29
  30   isPortraitMode?: boolean
  31
  32   job?: Job
  33 }
  34
  35 interface HLSTranscodeOptions extends BaseTranscodeVODOptions {
  36   type: 'hls'
  37   copyCodecs: boolean
  38   hlsPlaylist: {
  39     videoFilename: string
  40   }
  41 }
  42
  43 interface HLSFromTSTranscodeOptions extends BaseTranscodeVODOptions {
  44   type: 'hls-from-ts'
  45
  46   isAAC: boolean
  47
  48   hlsPlaylist: {
  49     videoFilename: string
  50   }
  51 }
  52
  53 interface QuickTranscodeOptions extends BaseTranscodeVODOptions {
  54   type: 'quick-transcode'
  55 }
  56
  57 interface VideoTranscodeOptions extends BaseTranscodeVODOptions {
  58   type: 'video'
  59 }
  60
  61 interface MergeAudioTranscodeOptions extends BaseTranscodeVODOptions {
  62   type: 'merge-audio'
  63   audioPath: string
  64 }
  65
  66 interface OnlyAudioTranscodeOptions extends BaseTranscodeVODOptions {
  67   type: 'only-audio'
  68 }
  69
  70 type TranscodeVODOptions =
  71   HLSTranscodeOptions
  72   | HLSFromTSTranscodeOptions
  73   | VideoTranscodeOptions
  74   | MergeAudioTranscodeOptions
  75   | OnlyAudioTranscodeOptions
  76   | QuickTranscodeOptions
  77
  78 // ---------------------------------------------------------------------------
  79
  80 const builders: {
  81   [ type in TranscodeVODOptionsType ]: (c: FfmpegCommand, o?: TranscodeVODOptions) => Promise<FfmpegCommand> | FfmpegCommand
  82 } = {
  83   'quick-transcode': buildQuickTranscodeCommand,
  84   'hls': buildHLSVODCommand,
  85   'hls-from-ts': buildHLSVODFromTSCommand,
  86   'merge-audio': buildAudioMergeCommand,
  87   'only-audio': buildOnlyAudioCommand,
  88   'video': buildVODCommand
  89 }
  90
  91 async function transcodeVOD (options: TranscodeVODOptions) {
  92   logger.debug('Will run transcode.', { options, ...lTags() })
  93
  94   let command = getFFmpeg(options.inputPath, 'vod')
  95     .output(options.outputPath)
  96
  97   command = await builders[options.type](command, options)
  98
  99   await runCommand({ command, job: options.job })
 100
 101   await fixHLSPlaylistIfNeeded(options)
 102 }
 103
 104 // ---------------------------------------------------------------------------
 105
 106 export {
 107   transcodeVOD,
 108
 109   buildVODCommand,
 110
 111   TranscodeVODOptions,
 112   TranscodeVODOptionsType
 113 }
 114
 115 // ---------------------------------------------------------------------------
 116
 117 async function buildVODCommand (command: FfmpegCommand, options: TranscodeVODOptions) {
 118   let fps = await getVideoStreamFPS(options.inputPath)
 119   fps = computeFPS(fps, options.resolution)
 120
 121   let scaleFilterValue: string
 122
 123   if (options.resolution !== undefined) {
 124     scaleFilterValue = options.isPortraitMode === true
 125       ? `w=${options.resolution}:h=-2`
 126       : `w=-2:h=${options.resolution}`
 127   }
 128
 129   command = await presetVOD({
 130     ...pick(options, [ 'resolution', 'availableEncoders', 'profile' ]),
 131
 132     command,
 133     input: options.inputPath,
 134     canCopyAudio: true,
 135     canCopyVideo: true,
 136     fps,
 137     scaleFilterValue
 138   })
 139
 140   return command
 141 }
 142
 143 function buildQuickTranscodeCommand (command: FfmpegCommand) {
 144   command = presetCopy(command)
 145
 146   command = command.outputOption('-map_metadata -1') // strip all metadata
 147                    .outputOption('-movflags faststart')
 148
 149   return command
 150 }
 151
 152 // ---------------------------------------------------------------------------
 153 // Audio transcoding
 154 // ---------------------------------------------------------------------------
 155
 156 async function buildAudioMergeCommand (command: FfmpegCommand, options: MergeAudioTranscodeOptions) {
 157   command = command.loop(undefined)
 158
 159   const scaleFilterValue = getMergeAudioScaleFilterValue()
 160   command = await presetVOD({
 161     ...pick(options, [ 'resolution', 'availableEncoders', 'profile' ]),
 162
 163     command,
 164     input: options.audioPath,
 165     canCopyAudio: true,
 166     canCopyVideo: true,
 167     fps: VIDEO_TRANSCODING_FPS.AUDIO_MERGE,
 168     scaleFilterValue
 169   })
 170
 171   command.outputOption('-preset:v veryfast')
 172
 173   command = command.input(options.audioPath)
 174                    .outputOption('-tune stillimage')
 175                    .outputOption('-shortest')
 176
 177   return command
 178 }
 179
 180 function buildOnlyAudioCommand (command: FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
 181   command = presetOnlyAudio(command)
 182
 183   return command
 184 }
 185
 186 // ---------------------------------------------------------------------------
 187 // HLS transcoding
 188 // ---------------------------------------------------------------------------
 189
 190 async function buildHLSVODCommand (command: FfmpegCommand, options: HLSTranscodeOptions) {
 191   const videoPath = getHLSVideoPath(options)
 192
 193   if (options.copyCodecs) command = presetCopy(command)
 194   else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
 195   else command = await buildVODCommand(command, options)
 196
 197   addCommonHLSVODCommandOptions(command, videoPath)
 198
 199   return command
 200 }
 201
 202 function buildHLSVODFromTSCommand (command: FfmpegCommand, options: HLSFromTSTranscodeOptions) {
 203   const videoPath = getHLSVideoPath(options)
 204
 205   command.outputOption('-c copy')
 206
 207   if (options.isAAC) {
 208     // Required for example when copying an AAC stream from an MPEG-TS
 209     // Since it's a bitstream filter, we don't need to reencode the audio
 210     command.outputOption('-bsf:a aac_adtstoasc')
 211   }
 212
 213   addCommonHLSVODCommandOptions(command, videoPath)
 214
 215   return command
 216 }
 217
 218 function addCommonHLSVODCommandOptions (command: FfmpegCommand, outputPath: string) {
 219   return command.outputOption('-hls_time 4')
 220                 .outputOption('-hls_list_size 0')
 221                 .outputOption('-hls_playlist_type vod')
 222                 .outputOption('-hls_segment_filename ' + outputPath)
 223                 .outputOption('-hls_segment_type fmp4')
 224                 .outputOption('-f hls')
 225                 .outputOption('-hls_flags single_file')
 226 }
 227
 228 async function fixHLSPlaylistIfNeeded (options: TranscodeVODOptions) {
 229   if (options.type !== 'hls' && options.type !== 'hls-from-ts') return
 230
 231   const fileContent = await readFile(options.outputPath)
 232
 233   const videoFileName = options.hlsPlaylist.videoFilename
 234   const videoFilePath = getHLSVideoPath(options)
 235
 236   // Fix wrong mapping with some ffmpeg versions
 237   const newContent = fileContent.toString()
 238                                 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
 239
 240   await writeFile(options.outputPath, newContent)
 241 }
 242
 243 // ---------------------------------------------------------------------------
 244 // Helpers
 245 // ---------------------------------------------------------------------------
 246
 247 function getHLSVideoPath (options: HLSTranscodeOptions | HLSFromTSTranscodeOptions) {
 248   return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
 249 }
 250
 251 // Avoid "height not divisible by 2" error
 252 function getMergeAudioScaleFilterValue () {
 253   return 'trunc(iw/2)*2:trunc(ih/2)*2'
 254 }