server/helpers/ffmpeg-utils.ts

   1 import { Job } from 'bull'
   2 import * as ffmpeg from 'fluent-ffmpeg'
   3 import { readFile, remove, writeFile } from 'fs-extra'
   4 import { dirname, join } from 'path'
   5 import { FFMPEG_NICE, VIDEO_LIVE } from '@server/initializers/constants'
   6 import { AvailableEncoders, EncoderOptionsBuilder, EncoderOptions, EncoderProfile, VideoResolution } from '../../shared/models/videos'
   7 import { CONFIG } from '../initializers/config'
   8 import { execPromise, promisify0 } from './core-utils'
   9 import { computeFPS, getAudioStream, getVideoFileFPS } from './ffprobe-utils'
  10 import { processImage } from './image-utils'
  11 import { logger } from './logger'
  12 import { FilterSpecification } from 'fluent-ffmpeg'
  13
  14 /**
  15  *
  16  * Functions that run transcoding/muxing ffmpeg processes
  17  * Mainly called by lib/video-transcoding.ts and lib/live-manager.ts
  18  *
  19  */
  20
  21 // ---------------------------------------------------------------------------
  22 // Encoder options
  23 // ---------------------------------------------------------------------------
  24
  25 type StreamType = 'audio' | 'video'
  26
  27 // ---------------------------------------------------------------------------
  28 // Encoders support
  29 // ---------------------------------------------------------------------------
  30
  31 // Detect supported encoders by ffmpeg
  32 let supportedEncoders: Map<string, boolean>
  33 async function checkFFmpegEncoders (peertubeAvailableEncoders: AvailableEncoders): Promise<Map<string, boolean>> {
  34   if (supportedEncoders !== undefined) {
  35     return supportedEncoders
  36   }
  37
  38   const getAvailableEncodersPromise = promisify0(ffmpeg.getAvailableEncoders)
  39   const availableFFmpegEncoders = await getAvailableEncodersPromise()
  40
  41   const searchEncoders = new Set<string>()
  42   for (const type of [ 'live', 'vod' ]) {
  43     for (const streamType of [ 'audio', 'video' ]) {
  44       for (const encoder of peertubeAvailableEncoders.encodersToTry[type][streamType]) {
  45         searchEncoders.add(encoder)
  46       }
  47     }
  48   }
  49
  50   supportedEncoders = new Map<string, boolean>()
  51
  52   for (const searchEncoder of searchEncoders) {
  53     supportedEncoders.set(searchEncoder, availableFFmpegEncoders[searchEncoder] !== undefined)
  54   }
  55
  56   logger.info('Built supported ffmpeg encoders.', { supportedEncoders, searchEncoders })
  57
  58   return supportedEncoders
  59 }
  60
  61 function resetSupportedEncoders () {
  62   supportedEncoders = undefined
  63 }
  64
  65 // ---------------------------------------------------------------------------
  66 // Image manipulation
  67 // ---------------------------------------------------------------------------
  68
  69 function convertWebPToJPG (path: string, destination: string): Promise<void> {
  70   const command = ffmpeg(path, { niceness: FFMPEG_NICE.THUMBNAIL })
  71     .output(destination)
  72
  73   return runCommand({ command, silent: true })
  74 }
  75
  76 function processGIF (
  77   path: string,
  78   destination: string,
  79   newSize: { width: number, height: number }
  80 ): Promise<void> {
  81   const command = ffmpeg(path, { niceness: FFMPEG_NICE.THUMBNAIL })
  82     .fps(20)
  83     .size(`${newSize.width}x${newSize.height}`)
  84     .output(destination)
  85
  86   return runCommand({ command })
  87 }
  88
  89 async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) {
  90   const pendingImageName = 'pending-' + imageName
  91
  92   const options = {
  93     filename: pendingImageName,
  94     count: 1,
  95     folder
  96   }
  97
  98   const pendingImagePath = join(folder, pendingImageName)
  99
 100   try {
 101     await new Promise<string>((res, rej) => {
 102       ffmpeg(fromPath, { niceness: FFMPEG_NICE.THUMBNAIL })
 103         .on('error', rej)
 104         .on('end', () => res(imageName))
 105         .thumbnail(options)
 106     })
 107
 108     const destination = join(folder, imageName)
 109     await processImage(pendingImagePath, destination, size)
 110   } catch (err) {
 111     logger.error('Cannot generate image from video %s.', fromPath, { err })
 112
 113     try {
 114       await remove(pendingImagePath)
 115     } catch (err) {
 116       logger.debug('Cannot remove pending image path after generation error.', { err })
 117     }
 118   }
 119 }
 120
 121 // ---------------------------------------------------------------------------
 122 // Transcode meta function
 123 // ---------------------------------------------------------------------------
 124
 125 type TranscodeOptionsType = 'hls' | 'hls-from-ts' | 'quick-transcode' | 'video' | 'merge-audio' | 'only-audio'
 126
 127 interface BaseTranscodeOptions {
 128   type: TranscodeOptionsType
 129
 130   inputPath: string
 131   outputPath: string
 132
 133   availableEncoders: AvailableEncoders
 134   profile: string
 135
 136   resolution: VideoResolution
 137
 138   isPortraitMode?: boolean
 139
 140   job?: Job
 141 }
 142
 143 interface HLSTranscodeOptions extends BaseTranscodeOptions {
 144   type: 'hls'
 145   copyCodecs: boolean
 146   hlsPlaylist: {
 147     videoFilename: string
 148   }
 149 }
 150
 151 interface HLSFromTSTranscodeOptions extends BaseTranscodeOptions {
 152   type: 'hls-from-ts'
 153
 154   isAAC: boolean
 155
 156   hlsPlaylist: {
 157     videoFilename: string
 158   }
 159 }
 160
 161 interface QuickTranscodeOptions extends BaseTranscodeOptions {
 162   type: 'quick-transcode'
 163 }
 164
 165 interface VideoTranscodeOptions extends BaseTranscodeOptions {
 166   type: 'video'
 167 }
 168
 169 interface MergeAudioTranscodeOptions extends BaseTranscodeOptions {
 170   type: 'merge-audio'
 171   audioPath: string
 172 }
 173
 174 interface OnlyAudioTranscodeOptions extends BaseTranscodeOptions {
 175   type: 'only-audio'
 176 }
 177
 178 type TranscodeOptions =
 179   HLSTranscodeOptions
 180   | HLSFromTSTranscodeOptions
 181   | VideoTranscodeOptions
 182   | MergeAudioTranscodeOptions
 183   | OnlyAudioTranscodeOptions
 184   | QuickTranscodeOptions
 185
 186 const builders: {
 187   [ type in TranscodeOptionsType ]: (c: ffmpeg.FfmpegCommand, o?: TranscodeOptions) => Promise<ffmpeg.FfmpegCommand> | ffmpeg.FfmpegCommand
 188 } = {
 189   'quick-transcode': buildQuickTranscodeCommand,
 190   'hls': buildHLSVODCommand,
 191   'hls-from-ts': buildHLSVODFromTSCommand,
 192   'merge-audio': buildAudioMergeCommand,
 193   'only-audio': buildOnlyAudioCommand,
 194   'video': buildx264VODCommand
 195 }
 196
 197 async function transcode (options: TranscodeOptions) {
 198   logger.debug('Will run transcode.', { options })
 199
 200   let command = getFFmpeg(options.inputPath, 'vod')
 201     .output(options.outputPath)
 202
 203   command = await builders[options.type](command, options)
 204
 205   await runCommand({ command, job: options.job })
 206
 207   await fixHLSPlaylistIfNeeded(options)
 208 }
 209
 210 // ---------------------------------------------------------------------------
 211 // Live muxing/transcoding functions
 212 // ---------------------------------------------------------------------------
 213
 214 async function getLiveTranscodingCommand (options: {
 215   rtmpUrl: string
 216   outPath: string
 217   resolutions: number[]
 218   fps: number
 219
 220   availableEncoders: AvailableEncoders
 221   profile: string
 222 }) {
 223   const { rtmpUrl, outPath, resolutions, fps, availableEncoders, profile } = options
 224   const input = rtmpUrl
 225
 226   const command = getFFmpeg(input, 'live')
 227
 228   const varStreamMap: string[] = []
 229
 230   const complexFilter: FilterSpecification[] = [
 231     {
 232       inputs: '[v:0]',
 233       filter: 'split',
 234       options: resolutions.length,
 235       outputs: resolutions.map(r => `vtemp${r}`)
 236     }
 237   ]
 238
 239   command.outputOption('-preset superfast')
 240   command.outputOption('-sc_threshold 0')
 241
 242   addDefaultEncoderGlobalParams({ command })
 243
 244   for (let i = 0; i < resolutions.length; i++) {
 245     const resolution = resolutions[i]
 246     const resolutionFPS = computeFPS(fps, resolution)
 247
 248     const baseEncoderBuilderParams = {
 249       input,
 250
 251       availableEncoders,
 252       profile,
 253
 254       fps: resolutionFPS,
 255       resolution,
 256       streamNum: i,
 257       videoType: 'live' as 'live'
 258     }
 259
 260     {
 261       const streamType: StreamType = 'video'
 262       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType }))
 263       if (!builderResult) {
 264         throw new Error('No available live video encoder found')
 265       }
 266
 267       command.outputOption(`-map [vout${resolution}]`)
 268
 269       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 270
 271       logger.debug('Apply ffmpeg live video params from %s using %s profile.', builderResult.encoder, profile, builderResult)
 272
 273       command.outputOption(`${buildStreamSuffix('-c:v', i)} ${builderResult.encoder}`)
 274       applyEncoderOptions(command, builderResult.result)
 275
 276       complexFilter.push({
 277         inputs: `vtemp${resolution}`,
 278         filter: getScaleFilter(builderResult.result),
 279         options: `w=-2:h=${resolution}`,
 280         outputs: `vout${resolution}`
 281       })
 282     }
 283
 284     {
 285       const streamType: StreamType = 'audio'
 286       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType }))
 287       if (!builderResult) {
 288         throw new Error('No available live audio encoder found')
 289       }
 290
 291       command.outputOption('-map a:0')
 292
 293       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 294
 295       logger.debug('Apply ffmpeg live audio params from %s using %s profile.', builderResult.encoder, profile, builderResult)
 296
 297       command.outputOption(`${buildStreamSuffix('-c:a', i)} ${builderResult.encoder}`)
 298       applyEncoderOptions(command, builderResult.result)
 299     }
 300
 301     varStreamMap.push(`v:${i},a:${i}`)
 302   }
 303
 304   command.complexFilter(complexFilter)
 305
 306   addDefaultLiveHLSParams(command, outPath)
 307
 308   command.outputOption('-var_stream_map', varStreamMap.join(' '))
 309
 310   return command
 311 }
 312
 313 function getLiveMuxingCommand (rtmpUrl: string, outPath: string) {
 314   const command = getFFmpeg(rtmpUrl, 'live')
 315
 316   command.outputOption('-c:v copy')
 317   command.outputOption('-c:a copy')
 318   command.outputOption('-map 0:a?')
 319   command.outputOption('-map 0:v?')
 320
 321   addDefaultLiveHLSParams(command, outPath)
 322
 323   return command
 324 }
 325
 326 function buildStreamSuffix (base: string, streamNum?: number) {
 327   if (streamNum !== undefined) {
 328     return `${base}:${streamNum}`
 329   }
 330
 331   return base
 332 }
 333
 334 // ---------------------------------------------------------------------------
 335 // Default options
 336 // ---------------------------------------------------------------------------
 337
 338 function addDefaultEncoderGlobalParams (options: {
 339   command: ffmpeg.FfmpegCommand
 340 }) {
 341   const { command } = options
 342
 343   // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375
 344   command.outputOption('-max_muxing_queue_size 1024')
 345          // strip all metadata
 346          .outputOption('-map_metadata -1')
 347          // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
 348          .outputOption('-b_strategy 1')
 349          // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
 350          .outputOption('-bf 16')
 351          // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
 352          .outputOption('-pix_fmt yuv420p')
 353 }
 354
 355 function addDefaultEncoderParams (options: {
 356   command: ffmpeg.FfmpegCommand
 357   encoder: 'libx264' | string
 358   streamNum?: number
 359   fps?: number
 360 }) {
 361   const { command, encoder, fps, streamNum } = options
 362
 363   if (encoder === 'libx264') {
 364     // 3.1 is the minimal resource allocation for our highest supported resolution
 365     command.outputOption(buildStreamSuffix('-level:v', streamNum) + ' 3.1')
 366
 367     if (fps) {
 368       // Keyframe interval of 2 seconds for faster seeking and resolution switching.
 369       // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
 370       // https://superuser.com/a/908325
 371       command.outputOption(buildStreamSuffix('-g:v', streamNum) + ' ' + (fps * 2))
 372     }
 373   }
 374 }
 375
 376 function addDefaultLiveHLSParams (command: ffmpeg.FfmpegCommand, outPath: string) {
 377   command.outputOption('-hls_time ' + VIDEO_LIVE.SEGMENT_TIME_SECONDS)
 378   command.outputOption('-hls_list_size ' + VIDEO_LIVE.SEGMENTS_LIST_SIZE)
 379   command.outputOption('-hls_flags delete_segments+independent_segments')
 380   command.outputOption(`-hls_segment_filename ${join(outPath, '%v-%06d.ts')}`)
 381   command.outputOption('-master_pl_name master.m3u8')
 382   command.outputOption(`-f hls`)
 383
 384   command.output(join(outPath, '%v.m3u8'))
 385 }
 386
 387 // ---------------------------------------------------------------------------
 388 // Transcode VOD command builders
 389 // ---------------------------------------------------------------------------
 390
 391 async function buildx264VODCommand (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
 392   let fps = await getVideoFileFPS(options.inputPath)
 393   fps = computeFPS(fps, options.resolution)
 394
 395   let scaleFilterValue: string
 396
 397   if (options.resolution !== undefined) {
 398     scaleFilterValue = options.isPortraitMode === true
 399       ? `w=${options.resolution}:h=-2`
 400       : `w=-2:h=${options.resolution}`
 401   }
 402
 403   command = await presetVideo({ command, input: options.inputPath, transcodeOptions: options, fps, scaleFilterValue })
 404
 405   return command
 406 }
 407
 408 async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
 409   command = command.loop(undefined)
 410
 411   // Avoid "height not divisible by 2" error
 412   const scaleFilterValue = 'trunc(iw/2)*2:trunc(ih/2)*2'
 413   command = await presetVideo({ command, input: options.audioPath, transcodeOptions: options, scaleFilterValue })
 414
 415   command.outputOption('-preset:v veryfast')
 416
 417   command = command.input(options.audioPath)
 418                    .outputOption('-tune stillimage')
 419                    .outputOption('-shortest')
 420
 421   return command
 422 }
 423
 424 function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
 425   command = presetOnlyAudio(command)
 426
 427   return command
 428 }
 429
 430 function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
 431   command = presetCopy(command)
 432
 433   command = command.outputOption('-map_metadata -1') // strip all metadata
 434                    .outputOption('-movflags faststart')
 435
 436   return command
 437 }
 438
 439 function addCommonHLSVODCommandOptions (command: ffmpeg.FfmpegCommand, outputPath: string) {
 440   return command.outputOption('-hls_time 4')
 441                 .outputOption('-hls_list_size 0')
 442                 .outputOption('-hls_playlist_type vod')
 443                 .outputOption('-hls_segment_filename ' + outputPath)
 444                 .outputOption('-hls_segment_type fmp4')
 445                 .outputOption('-f hls')
 446                 .outputOption('-hls_flags single_file')
 447 }
 448
 449 async function buildHLSVODCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
 450   const videoPath = getHLSVideoPath(options)
 451
 452   if (options.copyCodecs) command = presetCopy(command)
 453   else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
 454   else command = await buildx264VODCommand(command, options)
 455
 456   addCommonHLSVODCommandOptions(command, videoPath)
 457
 458   return command
 459 }
 460
 461 async function buildHLSVODFromTSCommand (command: ffmpeg.FfmpegCommand, options: HLSFromTSTranscodeOptions) {
 462   const videoPath = getHLSVideoPath(options)
 463
 464   command.outputOption('-c copy')
 465
 466   if (options.isAAC) {
 467     // Required for example when copying an AAC stream from an MPEG-TS
 468     // Since it's a bitstream filter, we don't need to reencode the audio
 469     command.outputOption('-bsf:a aac_adtstoasc')
 470   }
 471
 472   addCommonHLSVODCommandOptions(command, videoPath)
 473
 474   return command
 475 }
 476
 477 async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
 478   if (options.type !== 'hls' && options.type !== 'hls-from-ts') return
 479
 480   const fileContent = await readFile(options.outputPath)
 481
 482   const videoFileName = options.hlsPlaylist.videoFilename
 483   const videoFilePath = getHLSVideoPath(options)
 484
 485   // Fix wrong mapping with some ffmpeg versions
 486   const newContent = fileContent.toString()
 487                                 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
 488
 489   await writeFile(options.outputPath, newContent)
 490 }
 491
 492 function getHLSVideoPath (options: HLSTranscodeOptions | HLSFromTSTranscodeOptions) {
 493   return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
 494 }
 495
 496 // ---------------------------------------------------------------------------
 497 // Transcoding presets
 498 // ---------------------------------------------------------------------------
 499
 500 // Run encoder builder depending on available encoders
 501 // Try encoders by priority: if the encoder is available, run the chosen profile or fallback to the default one
 502 // If the default one does not exist, check the next encoder
 503 async function getEncoderBuilderResult (options: {
 504   streamType: 'video' | 'audio'
 505   input: string
 506
 507   availableEncoders: AvailableEncoders
 508   profile: string
 509
 510   videoType: 'vod' | 'live'
 511
 512   resolution: number
 513   fps?: number
 514   streamNum?: number
 515 }) {
 516   const { availableEncoders, input, profile, resolution, streamType, fps, streamNum, videoType } = options
 517
 518   const encodersToTry = availableEncoders.encodersToTry[videoType][streamType]
 519   const encoders = availableEncoders.available[videoType]
 520
 521   for (const encoder of encodersToTry) {
 522     if (!(await checkFFmpegEncoders(availableEncoders)).get(encoder)) {
 523       logger.debug('Encoder %s not available in ffmpeg, skipping.', encoder)
 524       continue
 525     }
 526
 527     if (!encoders[encoder]) {
 528       logger.debug('Encoder %s not available in peertube encoders, skipping.', encoder)
 529       continue
 530     }
 531
 532     // An object containing available profiles for this encoder
 533     const builderProfiles: EncoderProfile<EncoderOptionsBuilder> = encoders[encoder]
 534     let builder = builderProfiles[profile]
 535
 536     if (!builder) {
 537       logger.debug('Profile %s for encoder %s not available. Fallback to default.', profile, encoder)
 538       builder = builderProfiles.default
 539
 540       if (!builder) {
 541         logger.debug('Default profile for encoder %s not available. Try next available encoder.', encoder)
 542         continue
 543       }
 544     }
 545
 546     const result = await builder({ input, resolution: resolution, fps, streamNum })
 547
 548     return {
 549       result,
 550
 551       // If we don't have output options, then copy the input stream
 552       encoder: result.copy === true
 553         ? 'copy'
 554         : encoder
 555     }
 556   }
 557
 558   return null
 559 }
 560
 561 async function presetVideo (options: {
 562   command: ffmpeg.FfmpegCommand
 563   input: string
 564   transcodeOptions: TranscodeOptions
 565   fps?: number
 566   scaleFilterValue?: string
 567 }) {
 568   const { command, input, transcodeOptions, fps, scaleFilterValue } = options
 569
 570   let localCommand = command
 571     .format('mp4')
 572     .outputOption('-movflags faststart')
 573
 574   addDefaultEncoderGlobalParams({ command })
 575
 576   // Audio encoder
 577   const parsedAudio = await getAudioStream(input)
 578
 579   let streamsToProcess: StreamType[] = [ 'audio', 'video' ]
 580
 581   if (!parsedAudio.audioStream) {
 582     localCommand = localCommand.noAudio()
 583     streamsToProcess = [ 'video' ]
 584   }
 585
 586   for (const streamType of streamsToProcess) {
 587     const { profile, resolution, availableEncoders } = transcodeOptions
 588
 589     const builderResult = await getEncoderBuilderResult({
 590       streamType,
 591       input,
 592       resolution,
 593       availableEncoders,
 594       profile,
 595       fps,
 596       videoType: 'vod' as 'vod'
 597     })
 598
 599     if (!builderResult) {
 600       throw new Error('No available encoder found for stream ' + streamType)
 601     }
 602
 603     logger.debug(
 604       'Apply ffmpeg params from %s for %s stream of input %s using %s profile.',
 605       builderResult.encoder, streamType, input, profile, builderResult
 606     )
 607
 608     if (streamType === 'video') {
 609       localCommand.videoCodec(builderResult.encoder)
 610
 611       if (scaleFilterValue) {
 612         localCommand.outputOption(`-vf ${getScaleFilter(builderResult.result)}=${scaleFilterValue}`)
 613       }
 614     } else if (streamType === 'audio') {
 615       localCommand.audioCodec(builderResult.encoder)
 616     }
 617
 618     applyEncoderOptions(localCommand, builderResult.result)
 619     addDefaultEncoderParams({ command: localCommand, encoder: builderResult.encoder, fps })
 620   }
 621
 622   return localCommand
 623 }
 624
 625 function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 626   return command
 627     .format('mp4')
 628     .videoCodec('copy')
 629     .audioCodec('copy')
 630 }
 631
 632 function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 633   return command
 634     .format('mp4')
 635     .audioCodec('copy')
 636     .noVideo()
 637 }
 638
 639 function applyEncoderOptions (command: ffmpeg.FfmpegCommand, options: EncoderOptions): ffmpeg.FfmpegCommand {
 640   return command
 641     .inputOptions(options.inputOptions ?? [])
 642     .outputOptions(options.outputOptions ?? [])
 643 }
 644
 645 function getScaleFilter (options: EncoderOptions): string {
 646   if (options.scaleFilter) return options.scaleFilter.name
 647
 648   return 'scale'
 649 }
 650
 651 // ---------------------------------------------------------------------------
 652 // Utils
 653 // ---------------------------------------------------------------------------
 654
 655 function getFFmpeg (input: string, type: 'live' | 'vod') {
 656   // We set cwd explicitly because ffmpeg appears to create temporary files when trancoding which fails in read-only file systems
 657   const command = ffmpeg(input, {
 658     niceness: type === 'live' ? FFMPEG_NICE.LIVE : FFMPEG_NICE.VOD,
 659     cwd: CONFIG.STORAGE.TMP_DIR
 660   })
 661
 662   const threads = type === 'live'
 663     ? CONFIG.LIVE.TRANSCODING.THREADS
 664     : CONFIG.TRANSCODING.THREADS
 665
 666   if (threads > 0) {
 667     // If we don't set any threads ffmpeg will chose automatically
 668     command.outputOption('-threads ' + threads)
 669   }
 670
 671   return command
 672 }
 673
 674 function getFFmpegVersion () {
 675   return new Promise<string>((res, rej) => {
 676     (ffmpeg() as any)._getFfmpegPath((err, ffmpegPath) => {
 677       if (err) return rej(err)
 678       if (!ffmpegPath) return rej(new Error('Could not find ffmpeg path'))
 679
 680       return execPromise(`${ffmpegPath} -version`)
 681         .then(stdout => {
 682           const parsed = stdout.match(/ffmpeg version .?(\d+\.\d+\.\d+)/)
 683           if (!parsed || !parsed[1]) return rej(new Error(`Could not find ffmpeg version in ${stdout}`))
 684
 685           return res(parsed[1])
 686         })
 687         .catch(err => rej(err))
 688     })
 689   })
 690 }
 691
 692 async function runCommand (options: {
 693   command: ffmpeg.FfmpegCommand
 694   silent?: boolean // false
 695   job?: Job
 696 }) {
 697   const { command, silent = false, job } = options
 698
 699   return new Promise<void>((res, rej) => {
 700     command.on('error', (err, stdout, stderr) => {
 701       if (silent !== true) logger.error('Error in ffmpeg.', { stdout, stderr })
 702
 703       rej(err)
 704     })
 705
 706     command.on('end', (stdout, stderr) => {
 707       logger.debug('FFmpeg command ended.', { stdout, stderr })
 708
 709       res()
 710     })
 711
 712     if (job) {
 713       command.on('progress', progress => {
 714         if (!progress.percent) return
 715
 716         job.progress(Math.round(progress.percent))
 717           .catch(err => logger.warn('Cannot set ffmpeg job progress.', { err }))
 718       })
 719     }
 720
 721     command.run()
 722   })
 723 }
 724
 725 // ---------------------------------------------------------------------------
 726
 727 export {
 728   getLiveTranscodingCommand,
 729   getLiveMuxingCommand,
 730   buildStreamSuffix,
 731   convertWebPToJPG,
 732   processGIF,
 733   generateImageFromVideoFile,
 734   TranscodeOptions,
 735   TranscodeOptionsType,
 736   transcode,
 737   runCommand,
 738   getFFmpegVersion,
 739
 740   resetSupportedEncoders,
 741
 742   // builders
 743   buildx264VODCommand
 744 }