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' | 'hls-from-ts' | '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 HLSFromTSTranscodeOptions extends BaseTranscodeOptions {
 138   type: 'hls-from-ts'
 139
 140   isAAC: boolean
 141
 142   hlsPlaylist: {
 143     videoFilename: string
 144   }
 145 }
 146
 147 interface QuickTranscodeOptions extends BaseTranscodeOptions {
 148   type: 'quick-transcode'
 149 }
 150
 151 interface VideoTranscodeOptions extends BaseTranscodeOptions {
 152   type: 'video'
 153 }
 154
 155 interface MergeAudioTranscodeOptions extends BaseTranscodeOptions {
 156   type: 'merge-audio'
 157   audioPath: string
 158 }
 159
 160 interface OnlyAudioTranscodeOptions extends BaseTranscodeOptions {
 161   type: 'only-audio'
 162 }
 163
 164 type TranscodeOptions =
 165   HLSTranscodeOptions
 166   | HLSFromTSTranscodeOptions
 167   | VideoTranscodeOptions
 168   | MergeAudioTranscodeOptions
 169   | OnlyAudioTranscodeOptions
 170   | QuickTranscodeOptions
 171
 172 const builders: {
 173   [ type in TranscodeOptionsType ]: (c: ffmpeg.FfmpegCommand, o?: TranscodeOptions) => Promise<ffmpeg.FfmpegCommand> | ffmpeg.FfmpegCommand
 174 } = {
 175   'quick-transcode': buildQuickTranscodeCommand,
 176   'hls': buildHLSVODCommand,
 177   'hls-from-ts': buildHLSVODFromTSCommand,
 178   'merge-audio': buildAudioMergeCommand,
 179   'only-audio': buildOnlyAudioCommand,
 180   'video': buildx264VODCommand
 181 }
 182
 183 async function transcode (options: TranscodeOptions) {
 184   logger.debug('Will run transcode.', { options })
 185
 186   let command = getFFmpeg(options.inputPath, 'vod')
 187     .output(options.outputPath)
 188
 189   command = await builders[options.type](command, options)
 190
 191   await runCommand(command)
 192
 193   await fixHLSPlaylistIfNeeded(options)
 194 }
 195
 196 // ---------------------------------------------------------------------------
 197 // Live muxing/transcoding functions
 198 // ---------------------------------------------------------------------------
 199
 200 async function getLiveTranscodingCommand (options: {
 201   rtmpUrl: string
 202   outPath: string
 203   resolutions: number[]
 204   fps: number
 205
 206   availableEncoders: AvailableEncoders
 207   profile: string
 208 }) {
 209   const { rtmpUrl, outPath, resolutions, fps, availableEncoders, profile } = options
 210   const input = rtmpUrl
 211
 212   const command = getFFmpeg(input, 'live')
 213
 214   const varStreamMap: string[] = []
 215
 216   command.complexFilter([
 217     {
 218       inputs: '[v:0]',
 219       filter: 'split',
 220       options: resolutions.length,
 221       outputs: resolutions.map(r => `vtemp${r}`)
 222     },
 223
 224     ...resolutions.map(r => ({
 225       inputs: `vtemp${r}`,
 226       filter: 'scale',
 227       options: `w=-2:h=${r}`,
 228       outputs: `vout${r}`
 229     }))
 230   ])
 231
 232   command.outputOption('-preset superfast')
 233   command.outputOption('-sc_threshold 0')
 234
 235   addDefaultEncoderGlobalParams({ command })
 236
 237   for (let i = 0; i < resolutions.length; i++) {
 238     const resolution = resolutions[i]
 239     const resolutionFPS = computeFPS(fps, resolution)
 240
 241     const baseEncoderBuilderParams = {
 242       input,
 243       availableEncoders,
 244       profile,
 245       fps: resolutionFPS,
 246       resolution,
 247       streamNum: i,
 248       videoType: 'live' as 'live'
 249     }
 250
 251     {
 252       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'VIDEO' }))
 253       if (!builderResult) {
 254         throw new Error('No available live video encoder found')
 255       }
 256
 257       command.outputOption(`-map [vout${resolution}]`)
 258
 259       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 260
 261       logger.debug('Apply ffmpeg live video params from %s.', builderResult.encoder, builderResult)
 262
 263       command.outputOption(`${buildStreamSuffix('-c:v', i)} ${builderResult.encoder}`)
 264       command.addOutputOptions(builderResult.result.outputOptions)
 265     }
 266
 267     {
 268       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'AUDIO' }))
 269       if (!builderResult) {
 270         throw new Error('No available live audio encoder found')
 271       }
 272
 273       command.outputOption('-map a:0')
 274
 275       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 276
 277       logger.debug('Apply ffmpeg live audio params from %s.', builderResult.encoder, builderResult)
 278
 279       command.outputOption(`${buildStreamSuffix('-c:a', i)} ${builderResult.encoder}`)
 280       command.addOutputOptions(builderResult.result.outputOptions)
 281     }
 282
 283     varStreamMap.push(`v:${i},a:${i}`)
 284   }
 285
 286   addDefaultLiveHLSParams(command, outPath)
 287
 288   command.outputOption('-var_stream_map', varStreamMap.join(' '))
 289
 290   return command
 291 }
 292
 293 function getLiveMuxingCommand (rtmpUrl: string, outPath: string) {
 294   const command = getFFmpeg(rtmpUrl, 'live')
 295
 296   command.outputOption('-c:v copy')
 297   command.outputOption('-c:a copy')
 298   command.outputOption('-map 0:a?')
 299   command.outputOption('-map 0:v?')
 300
 301   addDefaultLiveHLSParams(command, outPath)
 302
 303   return command
 304 }
 305
 306 function buildStreamSuffix (base: string, streamNum?: number) {
 307   if (streamNum !== undefined) {
 308     return `${base}:${streamNum}`
 309   }
 310
 311   return base
 312 }
 313
 314 // ---------------------------------------------------------------------------
 315
 316 export {
 317   getLiveTranscodingCommand,
 318   getLiveMuxingCommand,
 319   buildStreamSuffix,
 320   convertWebPToJPG,
 321   processGIF,
 322   generateImageFromVideoFile,
 323   TranscodeOptions,
 324   TranscodeOptionsType,
 325   transcode
 326 }
 327
 328 // ---------------------------------------------------------------------------
 329
 330 // ---------------------------------------------------------------------------
 331 // Default options
 332 // ---------------------------------------------------------------------------
 333
 334 function addDefaultEncoderGlobalParams (options: {
 335   command: ffmpeg.FfmpegCommand
 336 }) {
 337   const { command } = options
 338
 339   // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375
 340   command.outputOption('-max_muxing_queue_size 1024')
 341          // strip all metadata
 342          .outputOption('-map_metadata -1')
 343          // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
 344          .outputOption('-b_strategy 1')
 345          // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
 346          .outputOption('-bf 16')
 347          // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
 348          .outputOption('-pix_fmt yuv420p')
 349 }
 350
 351 function addDefaultEncoderParams (options: {
 352   command: ffmpeg.FfmpegCommand
 353   encoder: 'libx264' | string
 354   streamNum?: number
 355   fps?: number
 356 }) {
 357   const { command, encoder, fps, streamNum } = options
 358
 359   if (encoder === 'libx264') {
 360     // 3.1 is the minimal resource allocation for our highest supported resolution
 361     command.outputOption(buildStreamSuffix('-level:v', streamNum) + ' 3.1')
 362
 363     if (fps) {
 364       // Keyframe interval of 2 seconds for faster seeking and resolution switching.
 365       // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
 366       // https://superuser.com/a/908325
 367       command.outputOption(buildStreamSuffix('-g:v', streamNum) + ' ' + (fps * 2))
 368     }
 369   }
 370 }
 371
 372 function addDefaultLiveHLSParams (command: ffmpeg.FfmpegCommand, outPath: string) {
 373   command.outputOption('-hls_time ' + VIDEO_LIVE.SEGMENT_TIME_SECONDS)
 374   command.outputOption('-hls_list_size ' + VIDEO_LIVE.SEGMENTS_LIST_SIZE)
 375   command.outputOption('-hls_flags delete_segments+independent_segments')
 376   command.outputOption(`-hls_segment_filename ${join(outPath, '%v-%06d.ts')}`)
 377   command.outputOption('-master_pl_name master.m3u8')
 378   command.outputOption(`-f hls`)
 379
 380   command.output(join(outPath, '%v.m3u8'))
 381 }
 382
 383 // ---------------------------------------------------------------------------
 384 // Transcode VOD command builders
 385 // ---------------------------------------------------------------------------
 386
 387 async function buildx264VODCommand (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
 388   let fps = await getVideoFileFPS(options.inputPath)
 389   fps = computeFPS(fps, options.resolution)
 390
 391   command = await presetVideo(command, options.inputPath, options, fps)
 392
 393   if (options.resolution !== undefined) {
 394     // '?x720' or '720x?' for example
 395     const size = options.isPortraitMode === true
 396       ? `${options.resolution}x?`
 397       : `?x${options.resolution}`
 398
 399     command = command.size(size)
 400   }
 401
 402   return command
 403 }
 404
 405 async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
 406   command = command.loop(undefined)
 407
 408   command = await presetVideo(command, options.audioPath, options)
 409
 410   command.outputOption('-preset:v veryfast')
 411
 412   command = command.input(options.audioPath)
 413                    .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
 414                    .outputOption('-tune stillimage')
 415                    .outputOption('-shortest')
 416
 417   return command
 418 }
 419
 420 function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
 421   command = presetOnlyAudio(command)
 422
 423   return command
 424 }
 425
 426 function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
 427   command = presetCopy(command)
 428
 429   command = command.outputOption('-map_metadata -1') // strip all metadata
 430                    .outputOption('-movflags faststart')
 431
 432   return command
 433 }
 434
 435 function addCommonHLSVODCommandOptions (command: ffmpeg.FfmpegCommand, outputPath: string) {
 436   return command.outputOption('-hls_time 4')
 437                 .outputOption('-hls_list_size 0')
 438                 .outputOption('-hls_playlist_type vod')
 439                 .outputOption('-hls_segment_filename ' + outputPath)
 440                 .outputOption('-hls_segment_type fmp4')
 441                 .outputOption('-f hls')
 442                 .outputOption('-hls_flags single_file')
 443 }
 444
 445 async function buildHLSVODCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
 446   const videoPath = getHLSVideoPath(options)
 447
 448   if (options.copyCodecs) command = presetCopy(command)
 449   else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
 450   else command = await buildx264VODCommand(command, options)
 451
 452   addCommonHLSVODCommandOptions(command, videoPath)
 453
 454   return command
 455 }
 456
 457 async function buildHLSVODFromTSCommand (command: ffmpeg.FfmpegCommand, options: HLSFromTSTranscodeOptions) {
 458   const videoPath = getHLSVideoPath(options)
 459
 460   command.outputOption('-c copy')
 461
 462   if (options.isAAC) {
 463     // Required for example when copying an AAC stream from an MPEG-TS
 464     // Since it's a bitstream filter, we don't need to reencode the audio
 465     command.outputOption('-bsf:a aac_adtstoasc')
 466   }
 467
 468   addCommonHLSVODCommandOptions(command, videoPath)
 469
 470   return command
 471 }
 472
 473 async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
 474   if (options.type !== 'hls' && options.type !== 'hls-from-ts') return
 475
 476   const fileContent = await readFile(options.outputPath)
 477
 478   const videoFileName = options.hlsPlaylist.videoFilename
 479   const videoFilePath = getHLSVideoPath(options)
 480
 481   // Fix wrong mapping with some ffmpeg versions
 482   const newContent = fileContent.toString()
 483                                 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
 484
 485   await writeFile(options.outputPath, newContent)
 486 }
 487
 488 function getHLSVideoPath (options: HLSTranscodeOptions | HLSFromTSTranscodeOptions) {
 489   return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
 490 }
 491
 492 // ---------------------------------------------------------------------------
 493 // Transcoding presets
 494 // ---------------------------------------------------------------------------
 495
 496 async function getEncoderBuilderResult (options: {
 497   streamType: string
 498   input: string
 499
 500   availableEncoders: AvailableEncoders
 501   profile: string
 502
 503   videoType: 'vod' | 'live'
 504
 505   resolution: number
 506   fps?: number
 507   streamNum?: number
 508 }) {
 509   const { availableEncoders, input, profile, resolution, streamType, fps, streamNum, videoType } = options
 510
 511   const encodersToTry: string[] = VIDEO_TRANSCODING_ENCODERS[streamType]
 512
 513   for (const encoder of encodersToTry) {
 514     if (!(await checkFFmpegEncoders()).get(encoder) || !availableEncoders[videoType][encoder]) continue
 515
 516     const builderProfiles: EncoderProfile<EncoderOptionsBuilder> = availableEncoders[videoType][encoder]
 517     let builder = builderProfiles[profile]
 518
 519     if (!builder) {
 520       logger.debug('Profile %s for encoder %s not available. Fallback to default.', profile, encoder)
 521       builder = builderProfiles.default
 522     }
 523
 524     const result = await builder({ input, resolution: resolution, fps, streamNum })
 525
 526     return {
 527       result,
 528
 529       // If we don't have output options, then copy the input stream
 530       encoder: result.copy === true
 531         ? 'copy'
 532         : encoder
 533     }
 534   }
 535
 536   return null
 537 }
 538
 539 async function presetVideo (
 540   command: ffmpeg.FfmpegCommand,
 541   input: string,
 542   transcodeOptions: TranscodeOptions,
 543   fps?: number
 544 ) {
 545   let localCommand = command
 546     .format('mp4')
 547     .outputOption('-movflags faststart')
 548
 549   addDefaultEncoderGlobalParams({ command })
 550
 551   // Audio encoder
 552   const parsedAudio = await getAudioStream(input)
 553
 554   let streamsToProcess = [ 'AUDIO', 'VIDEO' ]
 555
 556   if (!parsedAudio.audioStream) {
 557     localCommand = localCommand.noAudio()
 558     streamsToProcess = [ 'VIDEO' ]
 559   }
 560
 561   for (const streamType of streamsToProcess) {
 562     const { profile, resolution, availableEncoders } = transcodeOptions
 563
 564     const builderResult = await getEncoderBuilderResult({
 565       streamType,
 566       input,
 567       resolution,
 568       availableEncoders,
 569       profile,
 570       fps,
 571       videoType: 'vod' as 'vod'
 572     })
 573
 574     if (!builderResult) {
 575       throw new Error('No available encoder found for stream ' + streamType)
 576     }
 577
 578     logger.debug('Apply ffmpeg params from %s.', builderResult.encoder, builderResult)
 579
 580     if (streamType === 'VIDEO') {
 581       localCommand.videoCodec(builderResult.encoder)
 582     } else if (streamType === 'AUDIO') {
 583       localCommand.audioCodec(builderResult.encoder)
 584     }
 585
 586     command.addOutputOptions(builderResult.result.outputOptions)
 587     addDefaultEncoderParams({ command: localCommand, encoder: builderResult.encoder, fps })
 588   }
 589
 590   return localCommand
 591 }
 592
 593 function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 594   return command
 595     .format('mp4')
 596     .videoCodec('copy')
 597     .audioCodec('copy')
 598 }
 599
 600 function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 601   return command
 602     .format('mp4')
 603     .audioCodec('copy')
 604     .noVideo()
 605 }
 606
 607 // ---------------------------------------------------------------------------
 608 // Utils
 609 // ---------------------------------------------------------------------------
 610
 611 function getFFmpeg (input: string, type: 'live' | 'vod') {
 612   // We set cwd explicitly because ffmpeg appears to create temporary files when trancoding which fails in read-only file systems
 613   const command = ffmpeg(input, { niceness: FFMPEG_NICE.TRANSCODING, cwd: CONFIG.STORAGE.TMP_DIR })
 614
 615   const threads = type === 'live'
 616     ? CONFIG.LIVE.TRANSCODING.THREADS
 617     : CONFIG.TRANSCODING.THREADS
 618
 619   if (threads > 0) {
 620     // If we don't set any threads ffmpeg will chose automatically
 621     command.outputOption('-threads ' + threads)
 622   }
 623
 624   return command
 625 }
 626
 627 async function runCommand (command: ffmpeg.FfmpegCommand, onEnd?: Function) {
 628   return new Promise<void>((res, rej) => {
 629     command.on('error', (err, stdout, stderr) => {
 630       if (onEnd) onEnd()
 631
 632       logger.error('Error in transcoding job.', { stdout, stderr })
 633       rej(err)
 634     })
 635
 636     command.on('end', () => {
 637       if (onEnd) onEnd()
 638
 639       res()
 640     })
 641
 642     command.run()
 643   })
 644 }