1 import * as ffmpeg from 'fluent-ffmpeg'
2 import { dirname, join } from 'path'
3 import { getTargetBitrate, getMaxBitrate, VideoResolution } from '../../shared/models/videos'
4 import { FFMPEG_NICE, VIDEO_TRANSCODING_FPS } from '../initializers/constants'
5 import { processImage } from './image-utils'
6 import { logger } from './logger'
7 import { checkFFmpegEncoders } from '../initializers/checker-before-init'
8 import { readFile, remove, writeFile } from 'fs-extra'
9 import { CONFIG } from '../initializers/config'
11 function computeResolutionsToTranscode (videoFileHeight: number) {
12 const resolutionsEnabled: number[] = []
13 const configResolutions = CONFIG.TRANSCODING.RESOLUTIONS
15 // Put in the order we want to proceed jobs
17 VideoResolution.H_NOVIDEO,
18 VideoResolution.H_480P,
19 VideoResolution.H_360P,
20 VideoResolution.H_720P,
21 VideoResolution.H_240P,
22 VideoResolution.H_1080P,
26 for (const resolution of resolutions) {
27 if (configResolutions[ resolution + 'p' ] === true && videoFileHeight > resolution) {
28 resolutionsEnabled.push(resolution)
32 return resolutionsEnabled
35 async function getVideoStreamSize (path: string) {
36 const videoStream = await getVideoStreamFromFile(path)
38 return videoStream === null
39 ? { width: 0, height: 0 }
40 : { width: videoStream.width, height: videoStream.height }
43 async function getVideoStreamCodec (path: string) {
44 const videoStream = await getVideoStreamFromFile(path)
46 if (!videoStream) return ''
48 const videoCodec = videoStream.codec_tag_string
50 const baseProfileMatrix = {
56 let baseProfile = baseProfileMatrix[videoStream.profile]
58 logger.warn('Cannot get video profile codec of %s.', path, { videoStream })
59 baseProfile = baseProfileMatrix['High'] // Fallback
62 const level = videoStream.level.toString(16)
64 return `${videoCodec}.${baseProfile}${level}`
67 async function getAudioStreamCodec (path: string) {
68 const { audioStream } = await audio.get(path)
70 if (!audioStream) return ''
72 const audioCodec = audioStream.codec_name
73 if (audioCodec === 'aac') return 'mp4a.40.2'
75 logger.warn('Cannot get audio codec of %s.', path, { audioStream })
77 return 'mp4a.40.2' // Fallback
80 async function getVideoFileResolution (path: string) {
81 const size = await getVideoStreamSize(path)
84 videoFileResolution: Math.min(size.height, size.width),
85 isPortraitMode: size.height > size.width
89 async function getVideoFileFPS (path: string) {
90 const videoStream = await getVideoStreamFromFile(path)
91 if (videoStream === null) return 0
93 for (const key of [ 'avg_frame_rate', 'r_frame_rate' ]) {
94 const valuesText: string = videoStream[ key ]
95 if (!valuesText) continue
97 const [ frames, seconds ] = valuesText.split('/')
98 if (!frames || !seconds) continue
100 const result = parseInt(frames, 10) / parseInt(seconds, 10)
101 if (result > 0) return Math.round(result)
107 async function getVideoFileBitrate (path: string) {
108 return new Promise<number>((res, rej) => {
109 ffmpeg.ffprobe(path, (err, metadata) => {
110 if (err) return rej(err)
112 return res(metadata.format.bit_rate)
117 function getDurationFromVideoFile (path: string) {
118 return new Promise<number>((res, rej) => {
119 ffmpeg.ffprobe(path, (err, metadata) => {
120 if (err) return rej(err)
122 return res(Math.floor(metadata.format.duration))
127 async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) {
128 const pendingImageName = 'pending-' + imageName
131 filename: pendingImageName,
136 const pendingImagePath = join(folder, pendingImageName)
139 await new Promise<string>((res, rej) => {
140 ffmpeg(fromPath, { niceness: FFMPEG_NICE.THUMBNAIL })
142 .on('end', () => res(imageName))
146 const destination = join(folder, imageName)
147 await processImage(pendingImagePath, destination, size)
149 logger.error('Cannot generate image from video %s.', fromPath, { err })
152 await remove(pendingImagePath)
154 logger.debug('Cannot remove pending image path after generation error.', { err })
159 type TranscodeOptionsType = 'hls' | 'quick-transcode' | 'video' | 'merge-audio' | 'only-audio'
161 interface BaseTranscodeOptions {
162 type: TranscodeOptionsType
165 resolution: VideoResolution
166 isPortraitMode?: boolean
169 interface HLSTranscodeOptions extends BaseTranscodeOptions {
173 videoFilename: string
177 interface QuickTranscodeOptions extends BaseTranscodeOptions {
178 type: 'quick-transcode'
181 interface VideoTranscodeOptions extends BaseTranscodeOptions {
185 interface MergeAudioTranscodeOptions extends BaseTranscodeOptions {
190 interface OnlyAudioTranscodeOptions extends BaseTranscodeOptions {
194 type TranscodeOptions = HLSTranscodeOptions
195 | VideoTranscodeOptions
196 | MergeAudioTranscodeOptions
197 | OnlyAudioTranscodeOptions
198 | QuickTranscodeOptions
200 function transcode (options: TranscodeOptions) {
201 return new Promise<void>(async (res, rej) => {
203 let command = ffmpeg(options.inputPath, { niceness: FFMPEG_NICE.TRANSCODING })
204 .output(options.outputPath)
206 if (options.type === 'quick-transcode') {
207 command = await buildQuickTranscodeCommand(command)
208 } else if (options.type === 'hls') {
209 command = await buildHLSCommand(command, options)
210 } else if (options.type === 'merge-audio') {
211 command = await buildAudioMergeCommand(command, options)
212 } else if (options.type === 'only-audio') {
213 command = await buildOnlyAudioCommand(command, options)
215 command = await buildx264Command(command, options)
218 if (CONFIG.TRANSCODING.THREADS > 0) {
219 // if we don't set any threads ffmpeg will chose automatically
220 command = command.outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
224 .on('error', (err, stdout, stderr) => {
225 logger.error('Error in transcoding job.', { stdout, stderr })
229 return fixHLSPlaylistIfNeeded(options)
231 .catch(err => rej(err))
240 async function canDoQuickTranscode (path: string): Promise<boolean> {
241 // NOTE: This could be optimized by running ffprobe only once (but it runs fast anyway)
242 const videoStream = await getVideoStreamFromFile(path)
243 const parsedAudio = await audio.get(path)
244 const fps = await getVideoFileFPS(path)
245 const bitRate = await getVideoFileBitrate(path)
246 const resolution = await getVideoFileResolution(path)
248 // check video params
249 if (videoStream == null) return false
250 if (videoStream[ 'codec_name' ] !== 'h264') return false
251 if (videoStream[ 'pix_fmt' ] !== 'yuv420p') return false
252 if (fps < VIDEO_TRANSCODING_FPS.MIN || fps > VIDEO_TRANSCODING_FPS.MAX) return false
253 if (bitRate > getMaxBitrate(resolution.videoFileResolution, fps, VIDEO_TRANSCODING_FPS)) return false
255 // check audio params (if audio stream exists)
256 if (parsedAudio.audioStream) {
257 if (parsedAudio.audioStream[ 'codec_name' ] !== 'aac') return false
259 const maxAudioBitrate = audio.bitrate[ 'aac' ](parsedAudio.audioStream[ 'bit_rate' ])
260 if (maxAudioBitrate !== -1 && parsedAudio.audioStream[ 'bit_rate' ] > maxAudioBitrate) return false
266 function getClosestFramerateStandard (fps: number, type: 'HD_STANDARD' | 'STANDARD'): number {
267 return VIDEO_TRANSCODING_FPS[type].slice(0)
268 .sort((a, b) => fps % a - fps % b)[0]
271 // ---------------------------------------------------------------------------
277 getVideoFileResolution,
278 getDurationFromVideoFile,
279 generateImageFromVideoFile,
281 TranscodeOptionsType,
284 computeResolutionsToTranscode,
290 // ---------------------------------------------------------------------------
292 async function buildx264Command (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
293 let fps = await getVideoFileFPS(options.inputPath)
295 // On small/medium resolutions, limit FPS
296 options.resolution !== undefined &&
297 options.resolution < VIDEO_TRANSCODING_FPS.KEEP_ORIGIN_FPS_RESOLUTION_MIN &&
298 fps > VIDEO_TRANSCODING_FPS.AVERAGE
300 // Get closest standard framerate by modulo: downsampling has to be done to a divisor of the nominal fps value
301 fps = getClosestFramerateStandard(fps, 'STANDARD')
304 command = await presetH264(command, options.inputPath, options.resolution, fps)
306 if (options.resolution !== undefined) {
307 // '?x720' or '720x?' for example
308 const size = options.isPortraitMode === true ? `${options.resolution}x?` : `?x${options.resolution}`
309 command = command.size(size)
314 if (fps > VIDEO_TRANSCODING_FPS.MAX) fps = getClosestFramerateStandard(fps, 'HD_STANDARD')
315 else if (fps < VIDEO_TRANSCODING_FPS.MIN) fps = VIDEO_TRANSCODING_FPS.MIN
317 command = command.withFPS(fps)
323 async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
324 command = command.loop(undefined)
326 command = await presetH264VeryFast(command, options.audioPath, options.resolution)
328 command = command.input(options.audioPath)
329 .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
330 .outputOption('-tune stillimage')
331 .outputOption('-shortest')
336 async function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, options: OnlyAudioTranscodeOptions) {
337 command = await presetOnlyAudio(command)
342 async function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
343 command = await presetCopy(command)
345 command = command.outputOption('-map_metadata -1') // strip all metadata
346 .outputOption('-movflags faststart')
351 async function buildHLSCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
352 const videoPath = getHLSVideoPath(options)
354 if (options.copyCodecs) command = await presetCopy(command)
355 else command = await buildx264Command(command, options)
357 command = command.outputOption('-hls_time 4')
358 .outputOption('-hls_list_size 0')
359 .outputOption('-hls_playlist_type vod')
360 .outputOption('-hls_segment_filename ' + videoPath)
361 .outputOption('-hls_segment_type fmp4')
362 .outputOption('-f hls')
363 .outputOption('-hls_flags single_file')
368 function getHLSVideoPath (options: HLSTranscodeOptions) {
369 return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
372 async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
373 if (options.type !== 'hls') return
375 const fileContent = await readFile(options.outputPath)
377 const videoFileName = options.hlsPlaylist.videoFilename
378 const videoFilePath = getHLSVideoPath(options)
380 // Fix wrong mapping with some ffmpeg versions
381 const newContent = fileContent.toString()
382 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
384 await writeFile(options.outputPath, newContent)
387 function getVideoStreamFromFile (path: string) {
388 return new Promise<any>((res, rej) => {
389 ffmpeg.ffprobe(path, (err, metadata) => {
390 if (err) return rej(err)
392 const videoStream = metadata.streams.find(s => s.codec_type === 'video')
393 return res(videoStream || null)
399 * A slightly customised version of the 'veryfast' x264 preset
401 * The veryfast preset is right in the sweet spot of performance
402 * and quality. Superfast and ultrafast will give you better
403 * performance, but then quality is noticeably worse.
405 async function presetH264VeryFast (command: ffmpeg.FfmpegCommand, input: string, resolution: VideoResolution, fps?: number) {
406 let localCommand = await presetH264(command, input, resolution, fps)
408 localCommand = localCommand.outputOption('-preset:v veryfast')
411 MAIN reference: https://slhck.info/video/2017/03/01/rate-control.html
412 Our target situation is closer to a livestream than a stream,
413 since we want to reduce as much a possible the encoding burden,
414 although not to the point of a livestream where there is a hard
415 constraint on the frames per second to be encoded.
422 * A toolbox to play with audio
425 export const get = (videoPath: string) => {
426 // without position, ffprobe considers the last input only
427 // we make it consider the first input only
428 // if you pass a file path to pos, then ffprobe acts on that file directly
429 return new Promise<{ absolutePath: string, audioStream?: any }>((res, rej) => {
431 function parseFfprobe (err: any, data: ffmpeg.FfprobeData) {
432 if (err) return rej(err)
434 if ('streams' in data) {
435 const audioStream = data.streams.find(stream => stream[ 'codec_type' ] === 'audio')
438 absolutePath: data.format.filename,
444 return res({ absolutePath: data.format.filename })
447 return ffmpeg.ffprobe(videoPath, parseFfprobe)
451 export namespace bitrate {
452 const baseKbitrate = 384
454 const toBits = (kbits: number) => kbits * 8000
456 export const aac = (bitrate: number): number => {
458 case bitrate > toBits(baseKbitrate):
462 return -1 // we interpret it as a signal to copy the audio stream as is
466 export const mp3 = (bitrate: number): number => {
468 a 192kbit/sec mp3 doesn't hold as much information as a 192kbit/sec aac.
469 That's why, when using aac, we can go to lower kbit/sec. The equivalences
470 made here are not made to be accurate, especially with good mp3 encoders.
473 case bitrate <= toBits(192):
476 case bitrate <= toBits(384):
487 * Standard profile, with variable bitrate audio and faststart.
489 * As for the audio, quality '5' is the highest and ensures 96-112kbps/channel
490 * See https://trac.ffmpeg.org/wiki/Encode/AAC#fdk_vbr
492 async function presetH264 (command: ffmpeg.FfmpegCommand, input: string, resolution: VideoResolution, fps?: number) {
493 let localCommand = command
495 .videoCodec('libx264')
496 .outputOption('-level 3.1') // 3.1 is the minimal resource allocation for our highest supported resolution
497 .outputOption('-b_strategy 1') // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
498 .outputOption('-bf 16') // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
499 .outputOption('-pix_fmt yuv420p') // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
500 .outputOption('-map_metadata -1') // strip all metadata
501 .outputOption('-movflags faststart')
503 const parsedAudio = await audio.get(input)
505 if (!parsedAudio.audioStream) {
506 localCommand = localCommand.noAudio()
507 } else if ((await checkFFmpegEncoders()).get('libfdk_aac')) { // we favor VBR, if a good AAC encoder is available
508 localCommand = localCommand
509 .audioCodec('libfdk_aac')
512 // we try to reduce the ceiling bitrate by making rough matches of bitrates
513 // of course this is far from perfect, but it might save some space in the end
514 localCommand = localCommand.audioCodec('aac')
516 const audioCodecName = parsedAudio.audioStream[ 'codec_name' ]
518 if (audio.bitrate[ audioCodecName ]) {
519 const bitrate = audio.bitrate[ audioCodecName ](parsedAudio.audioStream[ 'bit_rate' ])
520 if (bitrate !== undefined && bitrate !== -1) localCommand = localCommand.audioBitrate(bitrate)
525 // Constrained Encoding (VBV)
526 // https://slhck.info/video/2017/03/01/rate-control.html
527 // https://trac.ffmpeg.org/wiki/Limiting%20the%20output%20bitrate
528 const targetBitrate = getTargetBitrate(resolution, fps, VIDEO_TRANSCODING_FPS)
529 localCommand = localCommand.outputOptions([ `-maxrate ${targetBitrate}`, `-bufsize ${targetBitrate * 2}` ])
531 // Keyframe interval of 2 seconds for faster seeking and resolution switching.
532 // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
533 // https://superuser.com/a/908325
534 localCommand = localCommand.outputOption(`-g ${fps * 2}`)
540 async function presetCopy (command: ffmpeg.FfmpegCommand): Promise<ffmpeg.FfmpegCommand> {
547 async function presetOnlyAudio (command: ffmpeg.FfmpegCommand): Promise<ffmpeg.FfmpegCommand> {