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
 194   availableEncoders: AvailableEncoders
 195   profile: string
 196 }) {
 197   const { rtmpUrl, outPath, resolutions, fps, availableEncoders, profile } = options
 198   const input = rtmpUrl
 199
 200   const command = getFFmpeg(input)
 201   command.inputOption('-fflags nobuffer')
 202
 203   const varStreamMap: string[] = []
 204
 205   command.complexFilter([
 206     {
 207       inputs: '[v:0]',
 208       filter: 'split',
 209       options: resolutions.length,
 210       outputs: resolutions.map(r => `vtemp${r}`)
 211     },
 212
 213     ...resolutions.map(r => ({
 214       inputs: `vtemp${r}`,
 215       filter: 'scale',
 216       options: `w=-2:h=${r}`,
 217       outputs: `vout${r}`
 218     }))
 219   ])
 220
 221   command.outputOption('-preset superfast')
 222
 223   addDefaultEncoderGlobalParams({ command })
 224
 225   for (let i = 0; i < resolutions.length; i++) {
 226     const resolution = resolutions[i]
 227     const resolutionFPS = computeFPS(fps, resolution)
 228
 229     const baseEncoderBuilderParams = {
 230       input,
 231       availableEncoders,
 232       profile,
 233       fps: resolutionFPS,
 234       resolution,
 235       streamNum: i,
 236       videoType: 'live' as 'live'
 237     }
 238
 239     {
 240       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'VIDEO' }))
 241       if (!builderResult) {
 242         throw new Error('No available live video encoder found')
 243       }
 244
 245       command.outputOption(`-map [vout${resolution}]`)
 246
 247       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 248
 249       logger.debug('Apply ffmpeg live video params from %s.', builderResult.encoder, builderResult)
 250
 251       command.outputOption(`${buildStreamSuffix('-c:v', i)} ${builderResult.encoder}`)
 252       command.addOutputOptions(builderResult.result.outputOptions)
 253     }
 254
 255     {
 256       const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'AUDIO' }))
 257       if (!builderResult) {
 258         throw new Error('No available live audio encoder found')
 259       }
 260
 261       command.outputOption('-map a:0')
 262
 263       addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps: resolutionFPS, streamNum: i })
 264
 265       logger.debug('Apply ffmpeg live audio params from %s.', builderResult.encoder, builderResult)
 266
 267       command.outputOption(`${buildStreamSuffix('-c:a', i)} ${builderResult.encoder}`)
 268       command.addOutputOptions(builderResult.result.outputOptions)
 269     }
 270
 271     varStreamMap.push(`v:${i},a:${i}`)
 272   }
 273
 274   addDefaultLiveHLSParams(command, outPath)
 275
 276   command.outputOption('-var_stream_map', varStreamMap.join(' '))
 277
 278   return command
 279 }
 280
 281 function getLiveMuxingCommand (rtmpUrl: string, outPath: string) {
 282   const command = getFFmpeg(rtmpUrl)
 283   command.inputOption('-fflags nobuffer')
 284
 285   command.outputOption('-c:v copy')
 286   command.outputOption('-c:a copy')
 287   command.outputOption('-map 0:a?')
 288   command.outputOption('-map 0:v?')
 289
 290   addDefaultLiveHLSParams(command, outPath)
 291
 292   return command
 293 }
 294
 295 async function hlsPlaylistToFragmentedMP4 (replayDirectory: string, segmentFiles: string[], outputPath: string) {
 296   const concatFilePath = join(replayDirectory, 'concat.txt')
 297
 298   function cleaner () {
 299     remove(concatFilePath)
 300       .catch(err => logger.error('Cannot remove concat file in %s.', replayDirectory, { err }))
 301   }
 302
 303   // First concat the ts files to a mp4 file
 304   const content = segmentFiles.map(f => 'file ' + f)
 305                               .join('\n')
 306
 307   await writeFile(concatFilePath, content + '\n')
 308
 309   const command = getFFmpeg(concatFilePath)
 310   command.inputOption('-safe 0')
 311   command.inputOption('-f concat')
 312
 313   command.outputOption('-c:v copy')
 314   command.audioFilter('aresample=async=1:first_pts=0')
 315   command.output(outputPath)
 316
 317   return runCommand(command, cleaner)
 318 }
 319
 320 function buildStreamSuffix (base: string, streamNum?: number) {
 321   if (streamNum !== undefined) {
 322     return `${base}:${streamNum}`
 323   }
 324
 325   return base
 326 }
 327
 328 // ---------------------------------------------------------------------------
 329
 330 export {
 331   getLiveTranscodingCommand,
 332   getLiveMuxingCommand,
 333   buildStreamSuffix,
 334   convertWebPToJPG,
 335   processGIF,
 336   generateImageFromVideoFile,
 337   TranscodeOptions,
 338   TranscodeOptionsType,
 339   transcode,
 340   hlsPlaylistToFragmentedMP4
 341 }
 342
 343 // ---------------------------------------------------------------------------
 344
 345 // ---------------------------------------------------------------------------
 346 // Default options
 347 // ---------------------------------------------------------------------------
 348
 349 function addDefaultEncoderGlobalParams (options: {
 350   command: ffmpeg.FfmpegCommand
 351 }) {
 352   const { command } = options
 353
 354   // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375
 355   command.outputOption('-max_muxing_queue_size 1024')
 356          // strip all metadata
 357          .outputOption('-map_metadata -1')
 358          // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
 359          .outputOption('-b_strategy 1')
 360          // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
 361          .outputOption('-bf 16')
 362          // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
 363          .outputOption('-pix_fmt yuv420p')
 364 }
 365
 366 function addDefaultEncoderParams (options: {
 367   command: ffmpeg.FfmpegCommand
 368   encoder: 'libx264' | string
 369   streamNum?: number
 370   fps?: number
 371 }) {
 372   const { command, encoder, fps, streamNum } = options
 373
 374   if (encoder === 'libx264') {
 375     // 3.1 is the minimal resource allocation for our highest supported resolution
 376     command.outputOption(buildStreamSuffix('-level:v', streamNum) + ' 3.1')
 377
 378     if (fps) {
 379       // Keyframe interval of 2 seconds for faster seeking and resolution switching.
 380       // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
 381       // https://superuser.com/a/908325
 382       command.outputOption(buildStreamSuffix('-g:v', streamNum) + ' ' + (fps * 2))
 383     }
 384   }
 385 }
 386
 387 function addDefaultLiveHLSParams (command: ffmpeg.FfmpegCommand, outPath: string) {
 388   command.outputOption('-hls_time ' + VIDEO_LIVE.SEGMENT_TIME_SECONDS)
 389   command.outputOption('-hls_list_size ' + VIDEO_LIVE.SEGMENTS_LIST_SIZE)
 390   command.outputOption('-hls_flags delete_segments')
 391   command.outputOption(`-hls_segment_filename ${join(outPath, '%v-%06d.ts')}`)
 392   command.outputOption('-master_pl_name master.m3u8')
 393   command.outputOption(`-f hls`)
 394
 395   command.output(join(outPath, '%v.m3u8'))
 396 }
 397
 398 // ---------------------------------------------------------------------------
 399 // Transcode VOD command builders
 400 // ---------------------------------------------------------------------------
 401
 402 async function buildx264VODCommand (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
 403   let fps = await getVideoFileFPS(options.inputPath)
 404   fps = computeFPS(fps, options.resolution)
 405
 406   command = await presetVideo(command, options.inputPath, options, fps)
 407
 408   if (options.resolution !== undefined) {
 409     // '?x720' or '720x?' for example
 410     const size = options.isPortraitMode === true
 411       ? `${options.resolution}x?`
 412       : `?x${options.resolution}`
 413
 414     command = command.size(size)
 415   }
 416
 417   return command
 418 }
 419
 420 async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
 421   command = command.loop(undefined)
 422
 423   command = await presetVideo(command, options.audioPath, options)
 424
 425   command.outputOption('-preset:v veryfast')
 426
 427   command = command.input(options.audioPath)
 428                    .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
 429                    .outputOption('-tune stillimage')
 430                    .outputOption('-shortest')
 431
 432   return command
 433 }
 434
 435 function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
 436   command = presetOnlyAudio(command)
 437
 438   return command
 439 }
 440
 441 function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
 442   command = presetCopy(command)
 443
 444   command = command.outputOption('-map_metadata -1') // strip all metadata
 445                    .outputOption('-movflags faststart')
 446
 447   return command
 448 }
 449
 450 async function buildHLSVODCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
 451   const videoPath = getHLSVideoPath(options)
 452
 453   if (options.copyCodecs) command = presetCopy(command)
 454   else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
 455   else command = await buildx264VODCommand(command, options)
 456
 457   command = command.outputOption('-hls_time 4')
 458                    .outputOption('-hls_list_size 0')
 459                    .outputOption('-hls_playlist_type vod')
 460                    .outputOption('-hls_segment_filename ' + videoPath)
 461                    .outputOption('-hls_segment_type fmp4')
 462                    .outputOption('-f hls')
 463                    .outputOption('-hls_flags single_file')
 464
 465   return command
 466 }
 467
 468 async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
 469   if (options.type !== 'hls') return
 470
 471   const fileContent = await readFile(options.outputPath)
 472
 473   const videoFileName = options.hlsPlaylist.videoFilename
 474   const videoFilePath = getHLSVideoPath(options)
 475
 476   // Fix wrong mapping with some ffmpeg versions
 477   const newContent = fileContent.toString()
 478                                 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
 479
 480   await writeFile(options.outputPath, newContent)
 481 }
 482
 483 function getHLSVideoPath (options: HLSTranscodeOptions) {
 484   return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
 485 }
 486
 487 // ---------------------------------------------------------------------------
 488 // Transcoding presets
 489 // ---------------------------------------------------------------------------
 490
 491 async function getEncoderBuilderResult (options: {
 492   streamType: string
 493   input: string
 494
 495   availableEncoders: AvailableEncoders
 496   profile: string
 497
 498   videoType: 'vod' | 'live'
 499
 500   resolution: number
 501   fps?: number
 502   streamNum?: number
 503 }) {
 504   const { availableEncoders, input, profile, resolution, streamType, fps, streamNum, videoType } = options
 505
 506   const encodersToTry: string[] = VIDEO_TRANSCODING_ENCODERS[streamType]
 507
 508   for (const encoder of encodersToTry) {
 509     if (!(await checkFFmpegEncoders()).get(encoder) || !availableEncoders[videoType][encoder]) continue
 510
 511     const builderProfiles: EncoderProfile<EncoderOptionsBuilder> = availableEncoders[videoType][encoder]
 512     let builder = builderProfiles[profile]
 513
 514     if (!builder) {
 515       logger.debug('Profile %s for encoder %s not available. Fallback to default.', profile, encoder)
 516       builder = builderProfiles.default
 517     }
 518
 519     const result = await builder({ input, resolution: resolution, fps, streamNum })
 520
 521     return {
 522       result,
 523
 524       // If we don't have output options, then copy the input stream
 525       encoder: result.copy === true
 526         ? 'copy'
 527         : encoder
 528     }
 529   }
 530
 531   return null
 532 }
 533
 534 async function presetVideo (
 535   command: ffmpeg.FfmpegCommand,
 536   input: string,
 537   transcodeOptions: TranscodeOptions,
 538   fps?: number
 539 ) {
 540   let localCommand = command
 541     .format('mp4')
 542     .outputOption('-movflags faststart')
 543
 544   addDefaultEncoderGlobalParams({ command })
 545
 546   // Audio encoder
 547   const parsedAudio = await getAudioStream(input)
 548
 549   let streamsToProcess = [ 'AUDIO', 'VIDEO' ]
 550
 551   if (!parsedAudio.audioStream) {
 552     localCommand = localCommand.noAudio()
 553     streamsToProcess = [ 'VIDEO' ]
 554   }
 555
 556   for (const streamType of streamsToProcess) {
 557     const { profile, resolution, availableEncoders } = transcodeOptions
 558
 559     const builderResult = await getEncoderBuilderResult({
 560       streamType,
 561       input,
 562       resolution,
 563       availableEncoders,
 564       profile,
 565       fps,
 566       videoType: 'vod' as 'vod'
 567     })
 568
 569     if (!builderResult) {
 570       throw new Error('No available encoder found for stream ' + streamType)
 571     }
 572
 573     logger.debug('Apply ffmpeg params from %s.', builderResult.encoder, builderResult)
 574
 575     if (streamType === 'VIDEO') {
 576       localCommand.videoCodec(builderResult.encoder)
 577     } else if (streamType === 'AUDIO') {
 578       localCommand.audioCodec(builderResult.encoder)
 579     }
 580
 581     command.addOutputOptions(builderResult.result.outputOptions)
 582     addDefaultEncoderParams({ command: localCommand, encoder: builderResult.encoder, fps })
 583   }
 584
 585   return localCommand
 586 }
 587
 588 function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 589   return command
 590     .format('mp4')
 591     .videoCodec('copy')
 592     .audioCodec('copy')
 593 }
 594
 595 function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 596   return command
 597     .format('mp4')
 598     .audioCodec('copy')
 599     .noVideo()
 600 }
 601
 602 // ---------------------------------------------------------------------------
 603 // Utils
 604 // ---------------------------------------------------------------------------
 605
 606 function getFFmpeg (input: string) {
 607   // We set cwd explicitly because ffmpeg appears to create temporary files when trancoding which fails in read-only file systems
 608   const command = ffmpeg(input, { niceness: FFMPEG_NICE.TRANSCODING, cwd: CONFIG.STORAGE.TMP_DIR })
 609
 610   if (CONFIG.TRANSCODING.THREADS > 0) {
 611     // If we don't set any threads ffmpeg will chose automatically
 612     command.outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
 613   }
 614
 615   return command
 616 }
 617
 618 async function runCommand (command: ffmpeg.FfmpegCommand, onEnd?: Function) {
 619   return new Promise<void>((res, rej) => {
 620     command.on('error', (err, stdout, stderr) => {
 621       if (onEnd) onEnd()
 622
 623       logger.error('Error in transcoding job.', { stdout, stderr })
 624       rej(err)
 625     })
 626
 627     command.on('end', () => {
 628       if (onEnd) onEnd()
 629
 630       res()
 631     })
 632
 633     command.run()
 634   })
 635 }