server/helpers/ffmpeg-utils.ts

   1 import * as ffmpeg from 'fluent-ffmpeg'
   2 import { readFile, remove, writeFile } from 'fs-extra'
   3 import { dirname, join } from 'path'
   4 import { FFMPEG_NICE, VIDEO_LIVE, VIDEO_TRANSCODING_ENCODERS } from '@server/initializers/constants'
   5 import { VideoResolution } from '../../shared/models/videos'
   6 import { checkFFmpegEncoders } from '../initializers/checker-before-init'
   7 import { CONFIG } from '../initializers/config'
   8 import { computeFPS, getAudioStream, getVideoFileFPS } from './ffprobe-utils'
   9 import { processImage } from './image-utils'
  10 import { logger } from './logger'
  11
  12 /**
  13  *
  14  * Functions that run transcoding/muxing ffmpeg processes
  15  * Mainly called by lib/video-transcoding.ts and lib/live-manager.ts
  16  *
  17  */
  18
  19 // ---------------------------------------------------------------------------
  20 // Encoder options
  21 // ---------------------------------------------------------------------------
  22
  23 // Options builders
  24
  25 export type EncoderOptionsBuilder = (params: {
  26   input: string
  27   resolution: VideoResolution
  28   fps?: number
  29   streamNum?: number
  30 }) => Promise<EncoderOptions> | EncoderOptions
  31
  32 // Options types
  33
  34 export interface EncoderOptions {
  35   copy?: boolean
  36   outputOptions: string[]
  37 }
  38
  39 // All our encoders
  40
  41 export interface EncoderProfile <T> {
  42   [ profile: string ]: T
  43
  44   default: T
  45 }
  46
  47 export type AvailableEncoders = {
  48   [ id in 'live' | 'vod' ]: {
  49     [ encoder in 'libx264' | 'aac' | 'libfdk_aac' ]?: EncoderProfile<EncoderOptionsBuilder>
  50   }
  51 }
  52
  53 // ---------------------------------------------------------------------------
  54 // Image manipulation
  55 // ---------------------------------------------------------------------------
  56
  57 function convertWebPToJPG (path: string, destination: string): Promise<void> {
  58   const command = ffmpeg(path)
  59     .output(destination)
  60
  61   return runCommand(command)
  62 }
  63
  64 function processGIF (
  65   path: string,
  66   destination: string,
  67   newSize: { width: number, height: number }
  68 ): Promise<void> {
  69   const command = ffmpeg(path)
  70     .fps(20)
  71     .size(`${newSize.width}x${newSize.height}`)
  72     .output(destination)
  73
  74   return runCommand(command)
  75 }
  76
  77 async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) {
  78   const pendingImageName = 'pending-' + imageName
  79
  80   const options = {
  81     filename: pendingImageName,
  82     count: 1,
  83     folder
  84   }
  85
  86   const pendingImagePath = join(folder, pendingImageName)
  87
  88   try {
  89     await new Promise<string>((res, rej) => {
  90       ffmpeg(fromPath, { niceness: FFMPEG_NICE.THUMBNAIL })
  91         .on('error', rej)
  92         .on('end', () => res(imageName))
  93         .thumbnail(options)
  94     })
  95
  96     const destination = join(folder, imageName)
  97     await processImage(pendingImagePath, destination, size)
  98   } catch (err) {
  99     logger.error('Cannot generate image from video %s.', fromPath, { err })
 100
 101     try {
 102       await remove(pendingImagePath)
 103     } catch (err) {
 104       logger.debug('Cannot remove pending image path after generation error.', { err })
 105     }
 106   }
 107 }
 108
 109 // ---------------------------------------------------------------------------
 110 // Transcode meta function
 111 // ---------------------------------------------------------------------------
 112
 113 type TranscodeOptionsType = 'hls' | 'quick-transcode' | 'video' | 'merge-audio' | 'only-audio'
 114
 115 interface BaseTranscodeOptions {
 116   type: TranscodeOptionsType
 117
 118   inputPath: string
 119   outputPath: string
 120
 121   availableEncoders: AvailableEncoders
 122   profile: string
 123
 124   resolution: VideoResolution
 125
 126   isPortraitMode?: boolean
 127 }
 128
 129 interface HLSTranscodeOptions extends BaseTranscodeOptions {
 130   type: 'hls'
 131   copyCodecs: boolean
 132   hlsPlaylist: {
 133     videoFilename: string
 134   }
 135 }
 136
 137 interface QuickTranscodeOptions extends BaseTranscodeOptions {
 138   type: 'quick-transcode'
 139 }
 140
 141 interface VideoTranscodeOptions extends BaseTranscodeOptions {
 142   type: 'video'
 143 }
 144
 145 interface MergeAudioTranscodeOptions extends BaseTranscodeOptions {
 146   type: 'merge-audio'
 147   audioPath: string
 148 }
 149
 150 interface OnlyAudioTranscodeOptions extends BaseTranscodeOptions {
 151   type: 'only-audio'
 152 }
 153
 154 type TranscodeOptions =
 155   HLSTranscodeOptions
 156   | VideoTranscodeOptions
 157   | MergeAudioTranscodeOptions
 158   | OnlyAudioTranscodeOptions
 159   | QuickTranscodeOptions
 160
 161 const builders: {
 162   [ type in TranscodeOptionsType ]: (c: ffmpeg.FfmpegCommand, o?: TranscodeOptions) => Promise<ffmpeg.FfmpegCommand> | ffmpeg.FfmpegCommand
 163 } = {
 164   'quick-transcode': buildQuickTranscodeCommand,
 165   'hls': buildHLSVODCommand,
 166   'merge-audio': buildAudioMergeCommand,
 167   'only-audio': buildOnlyAudioCommand,
 168   'video': buildx264VODCommand
 169 }
 170
 171 async function transcode (options: TranscodeOptions) {
 172   logger.debug('Will run transcode.', { options })
 173
 174   let command = getFFmpeg(options.inputPath)
 175     .output(options.outputPath)
 176
 177   command = await builders[options.type](command, options)
 178
 179   await runCommand(command)
 180
 181   await fixHLSPlaylistIfNeeded(options)
 182 }
 183
 184 // ---------------------------------------------------------------------------
 185 // Live muxing/transcoding functions
 186 // ---------------------------------------------------------------------------
 187
 188 async function getLiveTranscodingCommand (options: {
 189   rtmpUrl: string
 190   outPath: string
 191   resolutions: number[]
 192   fps: number
 193   deleteSegments: boolean
 194
 195   availableEncoders: AvailableEncoders
 196   profile: string
 197 }) {
 198   const { rtmpUrl, outPath, resolutions, fps, deleteSegments, availableEncoders, profile } = options
 199   const input = rtmpUrl
 200
 201   const command = getFFmpeg(input)
 202   command.inputOption('-fflags nobuffer')
 203
 204   const varStreamMap: string[] = []
 205
 206   command.complexFilter([
 207     {
 208       inputs: '[v:0]',
 209       filter: 'split',
 210       options: resolutions.length,
 211       outputs: resolutions.map(r => `vtemp${r}`)
 212     },
 213
 214     ...resolutions.map(r => ({
 215       inputs: `vtemp${r}`,
 216       filter: 'scale',
 217       options: `w=-2:h=${r}`,
 218       outputs: `vout${r}`
 219     }))
 220   ])
 221
 222   command.outputOption('-preset superfast')
 223
 224   for (let i = 0; i < resolutions.length; i++) {
 225     const resolution = resolutions[i]
 226     const resolutionFPS = computeFPS(fps, resolution)
 227
 228     const baseEncoderBuilderParams = {
 229       input,
 230       availableEncoders,
 231       profile,
 232       fps: resolutionFPS,
 233       resolution,
 234       streamNum: i,
 235       videoType: 'live' as 'live'
 236     }
 237
 238     {
 239       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'VIDEO' }))
 240       if (!builderResult) {
 241         throw new Error('No available live video encoder found')
 242       }
 243
 244       command.outputOption(`-map [vout${resolution}]`)
 245
 246       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 247
 248       logger.debug('Apply ffmpeg live video params from %s.', builderResult.encoder, builderResult)
 249
 250       command.outputOption(`${buildStreamSuffix('-c:v', i)} ${builderResult.encoder}`)
 251       command.addOutputOptions(builderResult.result.outputOptions)
 252     }
 253
 254     {
 255       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'AUDIO' }))
 256       if (!builderResult) {
 257         throw new Error('No available live audio encoder found')
 258       }
 259
 260       command.outputOption('-map a:0')
 261
 262       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 263
 264       logger.debug('Apply ffmpeg live audio params from %s.', builderResult.encoder, builderResult)
 265
 266       command.outputOption(`${buildStreamSuffix('-c:a', i)} ${builderResult.encoder}`)
 267       command.addOutputOptions(builderResult.result.outputOptions)
 268     }
 269
 270     varStreamMap.push(`v:${i},a:${i}`)
 271   }
 272
 273   addDefaultLiveHLSParams(command, outPath, deleteSegments)
 274
 275   command.outputOption('-var_stream_map', varStreamMap.join(' '))
 276
 277   return command
 278 }
 279
 280 function getLiveMuxingCommand (rtmpUrl: string, outPath: string, deleteSegments: boolean) {
 281   const command = getFFmpeg(rtmpUrl)
 282   command.inputOption('-fflags nobuffer')
 283
 284   command.outputOption('-c:v copy')
 285   command.outputOption('-c:a copy')
 286   command.outputOption('-map 0:a?')
 287   command.outputOption('-map 0:v?')
 288
 289   addDefaultLiveHLSParams(command, outPath, deleteSegments)
 290
 291   return command
 292 }
 293
 294 async function hlsPlaylistToFragmentedMP4 (hlsDirectory: string, segmentFiles: string[], outputPath: string) {
 295   const concatFilePath = join(hlsDirectory, 'concat.txt')
 296
 297   function cleaner () {
 298     remove(concatFilePath)
 299       .catch(err => logger.error('Cannot remove concat file in %s.', hlsDirectory, { err }))
 300   }
 301
 302   // First concat the ts files to a mp4 file
 303   const content = segmentFiles.map(f => 'file ' + f)
 304                               .join('\n')
 305
 306   await writeFile(concatFilePath, content + '\n')
 307
 308   const command = getFFmpeg(concatFilePath)
 309   command.inputOption('-safe 0')
 310   command.inputOption('-f concat')
 311
 312   command.outputOption('-c:v copy')
 313   command.audioFilter('aresample=async=1:first_pts=0')
 314   command.output(outputPath)
 315
 316   return runCommand(command, cleaner)
 317 }
 318
 319 function buildStreamSuffix (base: string, streamNum?: number) {
 320   if (streamNum !== undefined) {
 321     return `${base}:${streamNum}`
 322   }
 323
 324   return base
 325 }
 326
 327 // ---------------------------------------------------------------------------
 328
 329 export {
 330   getLiveTranscodingCommand,
 331   getLiveMuxingCommand,
 332   buildStreamSuffix,
 333   convertWebPToJPG,
 334   processGIF,
 335   generateImageFromVideoFile,
 336   TranscodeOptions,
 337   TranscodeOptionsType,
 338   transcode,
 339   hlsPlaylistToFragmentedMP4
 340 }
 341
 342 // ---------------------------------------------------------------------------
 343
 344 // ---------------------------------------------------------------------------
 345 // Default options
 346 // ---------------------------------------------------------------------------
 347
 348 function addDefaultEncoderParams (options: {
 349   command: ffmpeg.FfmpegCommand
 350   encoder: 'libx264' | string
 351   streamNum?: number
 352   fps?: number
 353 }) {
 354   const { command, encoder, fps, streamNum } = options
 355
 356   if (encoder === 'libx264') {
 357     // 3.1 is the minimal resource allocation for our highest supported resolution
 358     command.outputOption('-level 3.1')
 359         // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
 360         .outputOption('-b_strategy 1')
 361         // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
 362         .outputOption('-bf 16')
 363         // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
 364         .outputOption(buildStreamSuffix('-pix_fmt', streamNum) + ' yuv420p')
 365         // strip all metadata
 366         .outputOption('-map_metadata -1')
 367         // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375
 368         .outputOption(buildStreamSuffix('-max_muxing_queue_size', streamNum) + ' 1024')
 369
 370     if (fps) {
 371       // Keyframe interval of 2 seconds for faster seeking and resolution switching.
 372       // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
 373       // https://superuser.com/a/908325
 374       command.outputOption('-g ' + (fps * 2))
 375     }
 376   }
 377 }
 378
 379 function addDefaultLiveHLSParams (command: ffmpeg.FfmpegCommand, outPath: string, deleteSegments: boolean) {
 380   command.outputOption('-hls_time ' + VIDEO_LIVE.SEGMENT_TIME_SECONDS)
 381   command.outputOption('-hls_list_size ' + VIDEO_LIVE.SEGMENTS_LIST_SIZE)
 382
 383   if (deleteSegments === true) {
 384     command.outputOption('-hls_flags delete_segments')
 385   }
 386
 387   command.outputOption(`-hls_segment_filename ${join(outPath, '%v-%06d.ts')}`)
 388   command.outputOption('-master_pl_name master.m3u8')
 389   command.outputOption(`-f hls`)
 390
 391   command.output(join(outPath, '%v.m3u8'))
 392 }
 393
 394 // ---------------------------------------------------------------------------
 395 // Transcode VOD command builders
 396 // ---------------------------------------------------------------------------
 397
 398 async function buildx264VODCommand (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
 399   let fps = await getVideoFileFPS(options.inputPath)
 400   fps = computeFPS(fps, options.resolution)
 401
 402   command = await presetVideo(command, options.inputPath, options, fps)
 403
 404   if (options.resolution !== undefined) {
 405     // '?x720' or '720x?' for example
 406     const size = options.isPortraitMode === true
 407       ? `${options.resolution}x?`
 408       : `?x${options.resolution}`
 409
 410     command = command.size(size)
 411   }
 412
 413   return command
 414 }
 415
 416 async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
 417   command = command.loop(undefined)
 418
 419   command = await presetVideo(command, options.audioPath, options)
 420
 421   command.outputOption('-preset:v veryfast')
 422
 423   command = command.input(options.audioPath)
 424                    .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
 425                    .outputOption('-tune stillimage')
 426                    .outputOption('-shortest')
 427
 428   return command
 429 }
 430
 431 function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
 432   command = presetOnlyAudio(command)
 433
 434   return command
 435 }
 436
 437 function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
 438   command = presetCopy(command)
 439
 440   command = command.outputOption('-map_metadata -1') // strip all metadata
 441                    .outputOption('-movflags faststart')
 442
 443   return command
 444 }
 445
 446 async function buildHLSVODCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
 447   const videoPath = getHLSVideoPath(options)
 448
 449   if (options.copyCodecs) command = presetCopy(command)
 450   else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
 451   else command = await buildx264VODCommand(command, options)
 452
 453   command = command.outputOption('-hls_time 4')
 454                    .outputOption('-hls_list_size 0')
 455                    .outputOption('-hls_playlist_type vod')
 456                    .outputOption('-hls_segment_filename ' + videoPath)
 457                    .outputOption('-hls_segment_type fmp4')
 458                    .outputOption('-f hls')
 459                    .outputOption('-hls_flags single_file')
 460
 461   return command
 462 }
 463
 464 async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
 465   if (options.type !== 'hls') return
 466
 467   const fileContent = await readFile(options.outputPath)
 468
 469   const videoFileName = options.hlsPlaylist.videoFilename
 470   const videoFilePath = getHLSVideoPath(options)
 471
 472   // Fix wrong mapping with some ffmpeg versions
 473   const newContent = fileContent.toString()
 474                                 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
 475
 476   await writeFile(options.outputPath, newContent)
 477 }
 478
 479 function getHLSVideoPath (options: HLSTranscodeOptions) {
 480   return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
 481 }
 482
 483 // ---------------------------------------------------------------------------
 484 // Transcoding presets
 485 // ---------------------------------------------------------------------------
 486
 487 async function getEncoderBuilderResult (options: {
 488   streamType: string
 489   input: string
 490
 491   availableEncoders: AvailableEncoders
 492   profile: string
 493
 494   videoType: 'vod' | 'live'
 495
 496   resolution: number
 497   fps?: number
 498   streamNum?: number
 499 }) {
 500   const { availableEncoders, input, profile, resolution, streamType, fps, streamNum, videoType } = options
 501
 502   const encodersToTry: string[] = VIDEO_TRANSCODING_ENCODERS[streamType]
 503
 504   for (const encoder of encodersToTry) {
 505     if (!(await checkFFmpegEncoders()).get(encoder) || !availableEncoders[videoType][encoder]) continue
 506
 507     const builderProfiles: EncoderProfile<EncoderOptionsBuilder> = availableEncoders[videoType][encoder]
 508     let builder = builderProfiles[profile]
 509
 510     if (!builder) {
 511       logger.debug('Profile %s for encoder %s not available. Fallback to default.', profile, encoder)
 512       builder = builderProfiles.default
 513     }
 514
 515     const result = await builder({ input, resolution: resolution, fps, streamNum })
 516
 517     return {
 518       result,
 519
 520       // If we don't have output options, then copy the input stream
 521       encoder: result.copy === true
 522         ? 'copy'
 523         : encoder
 524     }
 525   }
 526
 527   return null
 528 }
 529
 530 async function presetVideo (
 531   command: ffmpeg.FfmpegCommand,
 532   input: string,
 533   transcodeOptions: TranscodeOptions,
 534   fps?: number
 535 ) {
 536   let localCommand = command
 537     .format('mp4')
 538     .outputOption('-movflags faststart')
 539
 540   // Audio encoder
 541   const parsedAudio = await getAudioStream(input)
 542
 543   let streamsToProcess = [ 'AUDIO', 'VIDEO' ]
 544
 545   if (!parsedAudio.audioStream) {
 546     localCommand = localCommand.noAudio()
 547     streamsToProcess = [ 'VIDEO' ]
 548   }
 549
 550   for (const streamType of streamsToProcess) {
 551     const { profile, resolution, availableEncoders } = transcodeOptions
 552
 553     const builderResult = await getEncoderBuilderResult({
 554       streamType,
 555       input,
 556       resolution,
 557       availableEncoders,
 558       profile,
 559       fps,
 560       videoType: 'vod' as 'vod'
 561     })
 562
 563     if (!builderResult) {
 564       throw new Error('No available encoder found for stream ' + streamType)
 565     }
 566
 567     logger.debug('Apply ffmpeg params from %s.', builderResult.encoder, builderResult)
 568
 569     if (streamType === 'VIDEO') {
 570       localCommand.videoCodec(builderResult.encoder)
 571     } else if (streamType === 'AUDIO') {
 572       localCommand.audioCodec(builderResult.encoder)
 573     }
 574
 575     command.addOutputOptions(builderResult.result.outputOptions)
 576     addDefaultEncoderParams({ command: localCommand, encoder: builderResult.encoder, fps })
 577   }
 578
 579   return localCommand
 580 }
 581
 582 function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 583   return command
 584     .format('mp4')
 585     .videoCodec('copy')
 586     .audioCodec('copy')
 587 }
 588
 589 function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 590   return command
 591     .format('mp4')
 592     .audioCodec('copy')
 593     .noVideo()
 594 }
 595
 596 // ---------------------------------------------------------------------------
 597 // Utils
 598 // ---------------------------------------------------------------------------
 599
 600 function getFFmpeg (input: string) {
 601   // We set cwd explicitly because ffmpeg appears to create temporary files when trancoding which fails in read-only file systems
 602   const command = ffmpeg(input, { niceness: FFMPEG_NICE.TRANSCODING, cwd: CONFIG.STORAGE.TMP_DIR })
 603
 604   if (CONFIG.TRANSCODING.THREADS > 0) {
 605     // If we don't set any threads ffmpeg will chose automatically
 606     command.outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
 607   }
 608
 609   return command
 610 }
 611
 612 async function runCommand (command: ffmpeg.FfmpegCommand, onEnd?: Function) {
 613   return new Promise<void>((res, rej) => {
 614     command.on('error', (err, stdout, stderr) => {
 615       if (onEnd) onEnd()
 616
 617       logger.error('Error in transcoding job.', { stdout, stderr })
 618       rej(err)
 619     })
 620
 621     command.on('end', () => {
 622       if (onEnd) onEnd()
 623
 624       res()
 625     })
 626
 627     command.run()
 628   })
 629 }