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 // Default options
 316 // ---------------------------------------------------------------------------
 317
 318 function addDefaultEncoderGlobalParams (options: {
 319   command: ffmpeg.FfmpegCommand
 320 }) {
 321   const { command } = options
 322
 323   // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375
 324   command.outputOption('-max_muxing_queue_size 1024')
 325          // strip all metadata
 326          .outputOption('-map_metadata -1')
 327          // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
 328          .outputOption('-b_strategy 1')
 329          // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
 330          .outputOption('-bf 16')
 331          // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
 332          .outputOption('-pix_fmt yuv420p')
 333 }
 334
 335 function addDefaultEncoderParams (options: {
 336   command: ffmpeg.FfmpegCommand
 337   encoder: 'libx264' | string
 338   streamNum?: number
 339   fps?: number
 340 }) {
 341   const { command, encoder, fps, streamNum } = options
 342
 343   if (encoder === 'libx264') {
 344     // 3.1 is the minimal resource allocation for our highest supported resolution
 345     command.outputOption(buildStreamSuffix('-level:v', streamNum) + ' 3.1')
 346
 347     if (fps) {
 348       // Keyframe interval of 2 seconds for faster seeking and resolution switching.
 349       // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
 350       // https://superuser.com/a/908325
 351       command.outputOption(buildStreamSuffix('-g:v', streamNum) + ' ' + (fps * 2))
 352     }
 353   }
 354 }
 355
 356 function addDefaultLiveHLSParams (command: ffmpeg.FfmpegCommand, outPath: string) {
 357   command.outputOption('-hls_time ' + VIDEO_LIVE.SEGMENT_TIME_SECONDS)
 358   command.outputOption('-hls_list_size ' + VIDEO_LIVE.SEGMENTS_LIST_SIZE)
 359   command.outputOption('-hls_flags delete_segments+independent_segments')
 360   command.outputOption(`-hls_segment_filename ${join(outPath, '%v-%06d.ts')}`)
 361   command.outputOption('-master_pl_name master.m3u8')
 362   command.outputOption(`-f hls`)
 363
 364   command.output(join(outPath, '%v.m3u8'))
 365 }
 366
 367 // ---------------------------------------------------------------------------
 368 // Transcode VOD command builders
 369 // ---------------------------------------------------------------------------
 370
 371 async function buildx264VODCommand (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
 372   let fps = await getVideoFileFPS(options.inputPath)
 373   fps = computeFPS(fps, options.resolution)
 374
 375   command = await presetVideo(command, options.inputPath, options, fps)
 376
 377   if (options.resolution !== undefined) {
 378     // '?x720' or '720x?' for example
 379     const size = options.isPortraitMode === true
 380       ? `${options.resolution}x?`
 381       : `?x${options.resolution}`
 382
 383     command = command.size(size)
 384   }
 385
 386   return command
 387 }
 388
 389 async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
 390   command = command.loop(undefined)
 391
 392   command = await presetVideo(command, options.audioPath, options)
 393
 394   command.outputOption('-preset:v veryfast')
 395
 396   command = command.input(options.audioPath)
 397                    .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
 398                    .outputOption('-tune stillimage')
 399                    .outputOption('-shortest')
 400
 401   return command
 402 }
 403
 404 function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
 405   command = presetOnlyAudio(command)
 406
 407   return command
 408 }
 409
 410 function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
 411   command = presetCopy(command)
 412
 413   command = command.outputOption('-map_metadata -1') // strip all metadata
 414                    .outputOption('-movflags faststart')
 415
 416   return command
 417 }
 418
 419 function addCommonHLSVODCommandOptions (command: ffmpeg.FfmpegCommand, outputPath: string) {
 420   return command.outputOption('-hls_time 4')
 421                 .outputOption('-hls_list_size 0')
 422                 .outputOption('-hls_playlist_type vod')
 423                 .outputOption('-hls_segment_filename ' + outputPath)
 424                 .outputOption('-hls_segment_type fmp4')
 425                 .outputOption('-f hls')
 426                 .outputOption('-hls_flags single_file')
 427 }
 428
 429 async function buildHLSVODCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
 430   const videoPath = getHLSVideoPath(options)
 431
 432   if (options.copyCodecs) command = presetCopy(command)
 433   else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
 434   else command = await buildx264VODCommand(command, options)
 435
 436   addCommonHLSVODCommandOptions(command, videoPath)
 437
 438   return command
 439 }
 440
 441 async function buildHLSVODFromTSCommand (command: ffmpeg.FfmpegCommand, options: HLSFromTSTranscodeOptions) {
 442   const videoPath = getHLSVideoPath(options)
 443
 444   command.outputOption('-c copy')
 445
 446   if (options.isAAC) {
 447     // Required for example when copying an AAC stream from an MPEG-TS
 448     // Since it's a bitstream filter, we don't need to reencode the audio
 449     command.outputOption('-bsf:a aac_adtstoasc')
 450   }
 451
 452   addCommonHLSVODCommandOptions(command, videoPath)
 453
 454   return command
 455 }
 456
 457 async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
 458   if (options.type !== 'hls' && options.type !== 'hls-from-ts') return
 459
 460   const fileContent = await readFile(options.outputPath)
 461
 462   const videoFileName = options.hlsPlaylist.videoFilename
 463   const videoFilePath = getHLSVideoPath(options)
 464
 465   // Fix wrong mapping with some ffmpeg versions
 466   const newContent = fileContent.toString()
 467                                 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
 468
 469   await writeFile(options.outputPath, newContent)
 470 }
 471
 472 function getHLSVideoPath (options: HLSTranscodeOptions | HLSFromTSTranscodeOptions) {
 473   return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
 474 }
 475
 476 // ---------------------------------------------------------------------------
 477 // Transcoding presets
 478 // ---------------------------------------------------------------------------
 479
 480 async function getEncoderBuilderResult (options: {
 481   streamType: string
 482   input: string
 483
 484   availableEncoders: AvailableEncoders
 485   profile: string
 486
 487   videoType: 'vod' | 'live'
 488
 489   resolution: number
 490   fps?: number
 491   streamNum?: number
 492 }) {
 493   const { availableEncoders, input, profile, resolution, streamType, fps, streamNum, videoType } = options
 494
 495   const encodersToTry: string[] = VIDEO_TRANSCODING_ENCODERS[streamType]
 496
 497   for (const encoder of encodersToTry) {
 498     if (!(await checkFFmpegEncoders()).get(encoder) || !availableEncoders[videoType][encoder]) continue
 499
 500     const builderProfiles: EncoderProfile<EncoderOptionsBuilder> = availableEncoders[videoType][encoder]
 501     let builder = builderProfiles[profile]
 502
 503     if (!builder) {
 504       logger.debug('Profile %s for encoder %s not available. Fallback to default.', profile, encoder)
 505       builder = builderProfiles.default
 506     }
 507
 508     const result = await builder({ input, resolution: resolution, fps, streamNum })
 509
 510     return {
 511       result,
 512
 513       // If we don't have output options, then copy the input stream
 514       encoder: result.copy === true
 515         ? 'copy'
 516         : encoder
 517     }
 518   }
 519
 520   return null
 521 }
 522
 523 async function presetVideo (
 524   command: ffmpeg.FfmpegCommand,
 525   input: string,
 526   transcodeOptions: TranscodeOptions,
 527   fps?: number
 528 ) {
 529   let localCommand = command
 530     .format('mp4')
 531     .outputOption('-movflags faststart')
 532
 533   addDefaultEncoderGlobalParams({ command })
 534
 535   // Audio encoder
 536   const parsedAudio = await getAudioStream(input)
 537
 538   let streamsToProcess = [ 'AUDIO', 'VIDEO' ]
 539
 540   if (!parsedAudio.audioStream) {
 541     localCommand = localCommand.noAudio()
 542     streamsToProcess = [ 'VIDEO' ]
 543   }
 544
 545   for (const streamType of streamsToProcess) {
 546     const { profile, resolution, availableEncoders } = transcodeOptions
 547
 548     const builderResult = await getEncoderBuilderResult({
 549       streamType,
 550       input,
 551       resolution,
 552       availableEncoders,
 553       profile,
 554       fps,
 555       videoType: 'vod' as 'vod'
 556     })
 557
 558     if (!builderResult) {
 559       throw new Error('No available encoder found for stream ' + streamType)
 560     }
 561
 562     logger.debug('Apply ffmpeg params from %s.', builderResult.encoder, builderResult)
 563
 564     if (streamType === 'VIDEO') {
 565       localCommand.videoCodec(builderResult.encoder)
 566     } else if (streamType === 'AUDIO') {
 567       localCommand.audioCodec(builderResult.encoder)
 568     }
 569
 570     command.addOutputOptions(builderResult.result.outputOptions)
 571     addDefaultEncoderParams({ command: localCommand, encoder: builderResult.encoder, fps })
 572   }
 573
 574   return localCommand
 575 }
 576
 577 function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 578   return command
 579     .format('mp4')
 580     .videoCodec('copy')
 581     .audioCodec('copy')
 582 }
 583
 584 function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
 585   return command
 586     .format('mp4')
 587     .audioCodec('copy')
 588     .noVideo()
 589 }
 590
 591 // ---------------------------------------------------------------------------
 592 // Utils
 593 // ---------------------------------------------------------------------------
 594
 595 function getFFmpeg (input: string, type: 'live' | 'vod') {
 596   // We set cwd explicitly because ffmpeg appears to create temporary files when trancoding which fails in read-only file systems
 597   const command = ffmpeg(input, {
 598     niceness: type === 'live' ? FFMPEG_NICE.LIVE : FFMPEG_NICE.VOD,
 599     cwd: CONFIG.STORAGE.TMP_DIR
 600   })
 601
 602   const threads = type === 'live'
 603     ? CONFIG.LIVE.TRANSCODING.THREADS
 604     : CONFIG.TRANSCODING.THREADS
 605
 606   if (threads > 0) {
 607     // If we don't set any threads ffmpeg will chose automatically
 608     command.outputOption('-threads ' + threads)
 609   }
 610
 611   return command
 612 }
 613
 614 async function runCommand (command: ffmpeg.FfmpegCommand, onEnd?: Function) {
 615   return new Promise<void>((res, rej) => {
 616     command.on('error', (err, stdout, stderr) => {
 617       if (onEnd) onEnd()
 618
 619       logger.error('Error in transcoding job.', { stdout, stderr })
 620       rej(err)
 621     })
 622
 623     command.on('end', (stdout, stderr) => {
 624       logger.debug('FFmpeg command ended.', { stdout, stderr })
 625
 626       if (onEnd) onEnd()
 627
 628       res()
 629     })
 630
 631     command.run()
 632   })
 633 }
 634
 635 // ---------------------------------------------------------------------------
 636
 637 export {
 638   getLiveTranscodingCommand,
 639   getLiveMuxingCommand,
 640   buildStreamSuffix,
 641   convertWebPToJPG,
 642   processGIF,
 643   generateImageFromVideoFile,
 644   TranscodeOptions,
 645   TranscodeOptionsType,
 646   transcode,
 647   runCommand,
 648
 649   // builders
 650   buildx264VODCommand
 651 }