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