1 import * as ffmpeg from 'fluent-ffmpeg'
2 import { dirname, join } from 'path'
3 import { getMaxBitrate, getTargetBitrate, 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'
10 import { VideoFileMetadata } from '@shared/models/videos/video-file-metadata'
13 * A toolbox to play with audio
16 export const get = (videoPath: string) => {
17 // without position, ffprobe considers the last input only
18 // we make it consider the first input only
19 // if you pass a file path to pos, then ffprobe acts on that file directly
20 return new Promise<{ absolutePath: string, audioStream?: any }>((res, rej) => {
22 function parseFfprobe (err: any, data: ffmpeg.FfprobeData) {
23 if (err) return rej(err)
25 if ('streams' in data) {
26 const audioStream = data.streams.find(stream => stream['codec_type'] === 'audio')
29 absolutePath: data.format.filename,
35 return res({ absolutePath: data.format.filename })
38 return ffmpeg.ffprobe(videoPath, parseFfprobe)
42 export namespace bitrate {
43 const baseKbitrate = 384
45 const toBits = (kbits: number) => kbits * 8000
47 export const aac = (bitrate: number): number => {
49 case bitrate > toBits(baseKbitrate):
53 return -1 // we interpret it as a signal to copy the audio stream as is
57 export const mp3 = (bitrate: number): number => {
59 a 192kbit/sec mp3 doesn't hold as much information as a 192kbit/sec aac.
60 That's why, when using aac, we can go to lower kbit/sec. The equivalences
61 made here are not made to be accurate, especially with good mp3 encoders.
64 case bitrate <= toBits(192):
67 case bitrate <= toBits(384):
77 function computeResolutionsToTranscode (videoFileResolution: number) {
78 const resolutionsEnabled: number[] = []
79 const configResolutions = CONFIG.TRANSCODING.RESOLUTIONS
81 // Put in the order we want to proceed jobs
83 VideoResolution.H_NOVIDEO,
84 VideoResolution.H_480P,
85 VideoResolution.H_360P,
86 VideoResolution.H_720P,
87 VideoResolution.H_240P,
88 VideoResolution.H_1080P,
92 for (const resolution of resolutions) {
93 if (configResolutions[resolution + 'p'] === true && videoFileResolution > resolution) {
94 resolutionsEnabled.push(resolution)
98 return resolutionsEnabled
101 async function getVideoStreamSize (path: string) {
102 const videoStream = await getVideoStreamFromFile(path)
104 return videoStream === null
105 ? { width: 0, height: 0 }
106 : { width: videoStream.width, height: videoStream.height }
109 async function getVideoStreamCodec (path: string) {
110 const videoStream = await getVideoStreamFromFile(path)
112 if (!videoStream) return ''
114 const videoCodec = videoStream.codec_tag_string
116 const baseProfileMatrix = {
122 let baseProfile = baseProfileMatrix[videoStream.profile]
124 logger.warn('Cannot get video profile codec of %s.', path, { videoStream })
125 baseProfile = baseProfileMatrix['High'] // Fallback
128 let level = videoStream.level.toString(16)
129 if (level.length === 1) level = `0${level}`
131 return `${videoCodec}.${baseProfile}${level}`
134 async function getAudioStreamCodec (path: string) {
135 const { audioStream } = await audio.get(path)
137 if (!audioStream) return ''
139 const audioCodec = audioStream.codec_name
140 if (audioCodec === 'aac') return 'mp4a.40.2'
142 logger.warn('Cannot get audio codec of %s.', path, { audioStream })
144 return 'mp4a.40.2' // Fallback
147 async function getVideoFileResolution (path: string) {
148 const size = await getVideoStreamSize(path)
151 videoFileResolution: Math.min(size.height, size.width),
152 isPortraitMode: size.height > size.width
156 async function getVideoFileFPS (path: string) {
157 const videoStream = await getVideoStreamFromFile(path)
158 if (videoStream === null) return 0
160 for (const key of [ 'avg_frame_rate', 'r_frame_rate' ]) {
161 const valuesText: string = videoStream[key]
162 if (!valuesText) continue
164 const [ frames, seconds ] = valuesText.split('/')
165 if (!frames || !seconds) continue
167 const result = parseInt(frames, 10) / parseInt(seconds, 10)
168 if (result > 0) return Math.round(result)
174 async function getMetadataFromFile <T> (path: string, cb = metadata => metadata) {
175 return new Promise<T>((res, rej) => {
176 ffmpeg.ffprobe(path, (err, metadata) => {
177 if (err) return rej(err)
179 return res(cb(new VideoFileMetadata(metadata)))
184 async function getVideoFileBitrate (path: string) {
185 return getMetadataFromFile<number>(path, metadata => metadata.format.bit_rate)
188 function getDurationFromVideoFile (path: string) {
189 return getMetadataFromFile<number>(path, metadata => Math.floor(metadata.format.duration))
192 function getVideoStreamFromFile (path: string) {
193 return getMetadataFromFile<any>(path, metadata => metadata.streams.find(s => s.codec_type === 'video') || null)
196 async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) {
197 const pendingImageName = 'pending-' + imageName
200 filename: pendingImageName,
205 const pendingImagePath = join(folder, pendingImageName)
208 await new Promise<string>((res, rej) => {
209 ffmpeg(fromPath, { niceness: FFMPEG_NICE.THUMBNAIL })
211 .on('end', () => res(imageName))
215 const destination = join(folder, imageName)
216 await processImage(pendingImagePath, destination, size)
218 logger.error('Cannot generate image from video %s.', fromPath, { err })
221 await remove(pendingImagePath)
223 logger.debug('Cannot remove pending image path after generation error.', { err })
228 type TranscodeOptionsType = 'hls' | 'quick-transcode' | 'video' | 'merge-audio' | 'only-audio'
230 interface BaseTranscodeOptions {
231 type: TranscodeOptionsType
234 resolution: VideoResolution
235 isPortraitMode?: boolean
238 interface HLSTranscodeOptions extends BaseTranscodeOptions {
242 videoFilename: string
246 interface QuickTranscodeOptions extends BaseTranscodeOptions {
247 type: 'quick-transcode'
250 interface VideoTranscodeOptions extends BaseTranscodeOptions {
254 interface MergeAudioTranscodeOptions extends BaseTranscodeOptions {
259 interface OnlyAudioTranscodeOptions extends BaseTranscodeOptions {
263 type TranscodeOptions =
265 | VideoTranscodeOptions
266 | MergeAudioTranscodeOptions
267 | OnlyAudioTranscodeOptions
268 | QuickTranscodeOptions
270 function transcode (options: TranscodeOptions) {
271 return new Promise<void>(async (res, rej) => {
273 let command = ffmpeg(options.inputPath, { niceness: FFMPEG_NICE.TRANSCODING })
274 .output(options.outputPath)
276 if (options.type === 'quick-transcode') {
277 command = buildQuickTranscodeCommand(command)
278 } else if (options.type === 'hls') {
279 command = await buildHLSCommand(command, options)
280 } else if (options.type === 'merge-audio') {
281 command = await buildAudioMergeCommand(command, options)
282 } else if (options.type === 'only-audio') {
283 command = buildOnlyAudioCommand(command, options)
285 command = await buildx264Command(command, options)
288 if (CONFIG.TRANSCODING.THREADS > 0) {
289 // if we don't set any threads ffmpeg will chose automatically
290 command = command.outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
294 .on('error', (err, stdout, stderr) => {
295 logger.error('Error in transcoding job.', { stdout, stderr })
299 return fixHLSPlaylistIfNeeded(options)
301 .catch(err => rej(err))
310 async function canDoQuickTranscode (path: string): Promise<boolean> {
311 // NOTE: This could be optimized by running ffprobe only once (but it runs fast anyway)
312 const videoStream = await getVideoStreamFromFile(path)
313 const parsedAudio = await audio.get(path)
314 const fps = await getVideoFileFPS(path)
315 const bitRate = await getVideoFileBitrate(path)
316 const resolution = await getVideoFileResolution(path)
318 // check video params
319 if (videoStream == null) return false
320 if (videoStream['codec_name'] !== 'h264') return false
321 if (videoStream['pix_fmt'] !== 'yuv420p') return false
322 if (fps < VIDEO_TRANSCODING_FPS.MIN || fps > VIDEO_TRANSCODING_FPS.MAX) return false
323 if (bitRate > getMaxBitrate(resolution.videoFileResolution, fps, VIDEO_TRANSCODING_FPS)) return false
325 // check audio params (if audio stream exists)
326 if (parsedAudio.audioStream) {
327 if (parsedAudio.audioStream['codec_name'] !== 'aac') return false
329 const maxAudioBitrate = audio.bitrate['aac'](parsedAudio.audioStream['bit_rate'])
330 if (maxAudioBitrate !== -1 && parsedAudio.audioStream['bit_rate'] > maxAudioBitrate) return false
336 function getClosestFramerateStandard (fps: number, type: 'HD_STANDARD' | 'STANDARD'): number {
337 return VIDEO_TRANSCODING_FPS[type].slice(0)
338 .sort((a, b) => fps % a - fps % b)[0]
341 function convertWebPToJPG (path: string, destination: string): Promise<void> {
342 return new Promise<void>(async (res, rej) => {
344 const command = ffmpeg(path).output(destination)
346 command.on('error', (err, stdout, stderr) => {
347 logger.error('Error in ffmpeg webp convert process.', { stdout, stderr })
350 .on('end', () => res())
358 // ---------------------------------------------------------------------------
365 getVideoFileResolution,
367 getDurationFromVideoFile,
368 generateImageFromVideoFile,
370 TranscodeOptionsType,
373 computeResolutionsToTranscode,
379 // ---------------------------------------------------------------------------
381 async function buildx264Command (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
382 let fps = await getVideoFileFPS(options.inputPath)
384 // On small/medium resolutions, limit FPS
385 options.resolution !== undefined &&
386 options.resolution < VIDEO_TRANSCODING_FPS.KEEP_ORIGIN_FPS_RESOLUTION_MIN &&
387 fps > VIDEO_TRANSCODING_FPS.AVERAGE
389 // Get closest standard framerate by modulo: downsampling has to be done to a divisor of the nominal fps value
390 fps = getClosestFramerateStandard(fps, 'STANDARD')
393 command = await presetH264(command, options.inputPath, options.resolution, fps)
395 if (options.resolution !== undefined) {
396 // '?x720' or '720x?' for example
397 const size = options.isPortraitMode === true ? `${options.resolution}x?` : `?x${options.resolution}`
398 command = command.size(size)
403 if (fps > VIDEO_TRANSCODING_FPS.MAX) fps = getClosestFramerateStandard(fps, 'HD_STANDARD')
404 else if (fps < VIDEO_TRANSCODING_FPS.MIN) fps = VIDEO_TRANSCODING_FPS.MIN
406 command = command.withFPS(fps)
412 async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
413 command = command.loop(undefined)
415 command = await presetH264VeryFast(command, options.audioPath, options.resolution)
417 command = command.input(options.audioPath)
418 .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
419 .outputOption('-tune stillimage')
420 .outputOption('-shortest')
425 function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, options: OnlyAudioTranscodeOptions) {
426 command = presetOnlyAudio(command)
431 function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
432 command = presetCopy(command)
434 command = command.outputOption('-map_metadata -1') // strip all metadata
435 .outputOption('-movflags faststart')
440 async function buildHLSCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
441 const videoPath = getHLSVideoPath(options)
443 if (options.copyCodecs) command = presetCopy(command)
444 else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
445 else command = await buildx264Command(command, options)
447 command = command.outputOption('-hls_time 4')
448 .outputOption('-hls_list_size 0')
449 .outputOption('-hls_playlist_type vod')
450 .outputOption('-hls_segment_filename ' + videoPath)
451 .outputOption('-hls_segment_type fmp4')
452 .outputOption('-f hls')
453 .outputOption('-hls_flags single_file')
458 function getHLSVideoPath (options: HLSTranscodeOptions) {
459 return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
462 async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
463 if (options.type !== 'hls') return
465 const fileContent = await readFile(options.outputPath)
467 const videoFileName = options.hlsPlaylist.videoFilename
468 const videoFilePath = getHLSVideoPath(options)
470 // Fix wrong mapping with some ffmpeg versions
471 const newContent = fileContent.toString()
472 .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
474 await writeFile(options.outputPath, newContent)
478 * A slightly customised version of the 'veryfast' x264 preset
480 * The veryfast preset is right in the sweet spot of performance
481 * and quality. Superfast and ultrafast will give you better
482 * performance, but then quality is noticeably worse.
484 async function presetH264VeryFast (command: ffmpeg.FfmpegCommand, input: string, resolution: VideoResolution, fps?: number) {
485 let localCommand = await presetH264(command, input, resolution, fps)
487 localCommand = localCommand.outputOption('-preset:v veryfast')
490 MAIN reference: https://slhck.info/video/2017/03/01/rate-control.html
491 Our target situation is closer to a livestream than a stream,
492 since we want to reduce as much a possible the encoding burden,
493 although not to the point of a livestream where there is a hard
494 constraint on the frames per second to be encoded.
501 * Standard profile, with variable bitrate audio and faststart.
503 * As for the audio, quality '5' is the highest and ensures 96-112kbps/channel
504 * See https://trac.ffmpeg.org/wiki/Encode/AAC#fdk_vbr
506 async function presetH264 (command: ffmpeg.FfmpegCommand, input: string, resolution: VideoResolution, fps?: number) {
507 let localCommand = command
509 .videoCodec('libx264')
510 .outputOption('-level 3.1') // 3.1 is the minimal resource allocation for our highest supported resolution
511 .outputOption('-b_strategy 1') // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
512 .outputOption('-bf 16') // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
513 .outputOption('-pix_fmt yuv420p') // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
514 .outputOption('-map_metadata -1') // strip all metadata
515 .outputOption('-movflags faststart')
517 const parsedAudio = await audio.get(input)
519 if (!parsedAudio.audioStream) {
520 localCommand = localCommand.noAudio()
521 } else if ((await checkFFmpegEncoders()).get('libfdk_aac')) { // we favor VBR, if a good AAC encoder is available
522 localCommand = localCommand
523 .audioCodec('libfdk_aac')
526 // we try to reduce the ceiling bitrate by making rough matches of bitrates
527 // of course this is far from perfect, but it might save some space in the end
528 localCommand = localCommand.audioCodec('aac')
530 const audioCodecName = parsedAudio.audioStream['codec_name']
532 if (audio.bitrate[audioCodecName]) {
533 const bitrate = audio.bitrate[audioCodecName](parsedAudio.audioStream['bit_rate'])
534 if (bitrate !== undefined && bitrate !== -1) localCommand = localCommand.audioBitrate(bitrate)
539 // Constrained Encoding (VBV)
540 // https://slhck.info/video/2017/03/01/rate-control.html
541 // https://trac.ffmpeg.org/wiki/Limiting%20the%20output%20bitrate
542 const targetBitrate = getTargetBitrate(resolution, fps, VIDEO_TRANSCODING_FPS)
543 localCommand = localCommand.outputOptions([ `-maxrate ${targetBitrate}`, `-bufsize ${targetBitrate * 2}` ])
545 // Keyframe interval of 2 seconds for faster seeking and resolution switching.
546 // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
547 // https://superuser.com/a/908325
548 localCommand = localCommand.outputOption(`-g ${fps * 2}`)
554 function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
561 function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {