PeerTube/server/helpers/ffmpeg-utils.ts

556 lines
17 KiB
TypeScript

import * as ffmpeg from 'fluent-ffmpeg'
import { readFile, remove, writeFile } from 'fs-extra'
import { dirname, join } from 'path'
import { getTargetBitrate, VideoResolution } from '../../shared/models/videos'
import { checkFFmpegEncoders } from '../initializers/checker-before-init'
import { CONFIG } from '../initializers/config'
import { FFMPEG_NICE, VIDEO_LIVE, VIDEO_TRANSCODING_ENCODERS, VIDEO_TRANSCODING_FPS } from '../initializers/constants'
import { getAudioStream, getClosestFramerateStandard, getVideoFileFPS } from './ffprobe-utils'
import { processImage } from './image-utils'
import { logger } from './logger'
// ---------------------------------------------------------------------------
// Encoder options
// ---------------------------------------------------------------------------
// Options builders
export type EncoderOptionsBuilder = (params: {
input: string
resolution: VideoResolution
fps?: number
}) => Promise<EncoderOptions> | EncoderOptions
// Options types
export interface EncoderOptions {
outputOptions: string[]
}
// All our encoders
export interface EncoderProfile <T> {
[ profile: string ]: T
default: T
}
export type AvailableEncoders = {
[ id in 'live' | 'vod' ]: {
[ encoder in 'libx264' | 'aac' | 'libfdkAAC' ]: EncoderProfile<EncoderOptionsBuilder>
}
}
// ---------------------------------------------------------------------------
// Image manipulation
// ---------------------------------------------------------------------------
function convertWebPToJPG (path: string, destination: string): Promise<void> {
const command = ffmpeg(path)
.output(destination)
return runCommand(command)
}
function processGIF (
path: string,
destination: string,
newSize: { width: number, height: number },
keepOriginal = false
): Promise<void> {
return new Promise<void>(async (res, rej) => {
if (path === destination) {
throw new Error('FFmpeg needs an input path different that the output path.')
}
logger.debug('Processing gif %s to %s.', path, destination)
try {
const command = ffmpeg(path)
.fps(20)
.size(`${newSize.width}x${newSize.height}`)
.output(destination)
command.on('error', (err, stdout, stderr) => {
logger.error('Error in ffmpeg gif resizing process.', { stdout, stderr })
return rej(err)
})
.on('end', async () => {
if (keepOriginal !== true) await remove(path)
res()
})
.run()
} catch (err) {
return rej(err)
}
})
}
async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) {
const pendingImageName = 'pending-' + imageName
const options = {
filename: pendingImageName,
count: 1,
folder
}
const pendingImagePath = join(folder, pendingImageName)
try {
await new Promise<string>((res, rej) => {
ffmpeg(fromPath, { niceness: FFMPEG_NICE.THUMBNAIL })
.on('error', rej)
.on('end', () => res(imageName))
.thumbnail(options)
})
const destination = join(folder, imageName)
await processImage(pendingImagePath, destination, size)
} catch (err) {
logger.error('Cannot generate image from video %s.', fromPath, { err })
try {
await remove(pendingImagePath)
} catch (err) {
logger.debug('Cannot remove pending image path after generation error.', { err })
}
}
}
// ---------------------------------------------------------------------------
// Transcode meta function
// ---------------------------------------------------------------------------
type TranscodeOptionsType = 'hls' | 'quick-transcode' | 'video' | 'merge-audio' | 'only-audio'
interface BaseTranscodeOptions {
type: TranscodeOptionsType
inputPath: string
outputPath: string
availableEncoders: AvailableEncoders
profile: string
resolution: VideoResolution
isPortraitMode?: boolean
}
interface HLSTranscodeOptions extends BaseTranscodeOptions {
type: 'hls'
copyCodecs: boolean
hlsPlaylist: {
videoFilename: string
}
}
interface QuickTranscodeOptions extends BaseTranscodeOptions {
type: 'quick-transcode'
}
interface VideoTranscodeOptions extends BaseTranscodeOptions {
type: 'video'
}
interface MergeAudioTranscodeOptions extends BaseTranscodeOptions {
type: 'merge-audio'
audioPath: string
}
interface OnlyAudioTranscodeOptions extends BaseTranscodeOptions {
type: 'only-audio'
}
type TranscodeOptions =
HLSTranscodeOptions
| VideoTranscodeOptions
| MergeAudioTranscodeOptions
| OnlyAudioTranscodeOptions
| QuickTranscodeOptions
const builders: {
[ type in TranscodeOptionsType ]: (c: ffmpeg.FfmpegCommand, o?: TranscodeOptions) => Promise<ffmpeg.FfmpegCommand> | ffmpeg.FfmpegCommand
} = {
'quick-transcode': buildQuickTranscodeCommand,
'hls': buildHLSVODCommand,
'merge-audio': buildAudioMergeCommand,
'only-audio': buildOnlyAudioCommand,
'video': buildx264VODCommand
}
async function transcode (options: TranscodeOptions) {
logger.debug('Will run transcode.', { options })
let command = getFFmpeg(options.inputPath)
.output(options.outputPath)
command = await builders[options.type](command, options)
await runCommand(command)
await fixHLSPlaylistIfNeeded(options)
}
// ---------------------------------------------------------------------------
// Live muxing/transcoding functions
// ---------------------------------------------------------------------------
function getLiveTranscodingCommand (rtmpUrl: string, outPath: string, resolutions: number[], fps: number, deleteSegments: boolean) {
const command = getFFmpeg(rtmpUrl)
command.inputOption('-fflags nobuffer')
const varStreamMap: string[] = []
command.complexFilter([
{
inputs: '[v:0]',
filter: 'split',
options: resolutions.length,
outputs: resolutions.map(r => `vtemp${r}`)
},
...resolutions.map(r => ({
inputs: `vtemp${r}`,
filter: 'scale',
options: `w=-2:h=${r}`,
outputs: `vout${r}`
}))
])
addEncoderDefaultParams(command, 'libx264', fps)
command.outputOption('-preset superfast')
for (let i = 0; i < resolutions.length; i++) {
const resolution = resolutions[i]
command.outputOption(`-map [vout${resolution}]`)
command.outputOption(`-c:v:${i} libx264`)
command.outputOption(`-b:v:${i} ${getTargetBitrate(resolution, fps, VIDEO_TRANSCODING_FPS)}`)
command.outputOption(`-map a:0`)
command.outputOption(`-c:a:${i} aac`)
varStreamMap.push(`v:${i},a:${i}`)
}
addDefaultLiveHLSParams(command, outPath, deleteSegments)
command.outputOption('-var_stream_map', varStreamMap.join(' '))
return command
}
function getLiveMuxingCommand (rtmpUrl: string, outPath: string, deleteSegments: boolean) {
const command = getFFmpeg(rtmpUrl)
command.inputOption('-fflags nobuffer')
command.outputOption('-c:v copy')
command.outputOption('-c:a copy')
command.outputOption('-map 0:a?')
command.outputOption('-map 0:v?')
addDefaultLiveHLSParams(command, outPath, deleteSegments)
return command
}
async function hlsPlaylistToFragmentedMP4 (hlsDirectory: string, segmentFiles: string[], outputPath: string) {
const concatFilePath = join(hlsDirectory, 'concat.txt')
function cleaner () {
remove(concatFilePath)
.catch(err => logger.error('Cannot remove concat file in %s.', hlsDirectory, { err }))
}
// First concat the ts files to a mp4 file
const content = segmentFiles.map(f => 'file ' + f)
.join('\n')
await writeFile(concatFilePath, content + '\n')
const command = getFFmpeg(concatFilePath)
command.inputOption('-safe 0')
command.inputOption('-f concat')
command.outputOption('-c:v copy')
command.audioFilter('aresample=async=1:first_pts=0')
command.output(outputPath)
return runCommand(command, cleaner)
}
// ---------------------------------------------------------------------------
export {
getLiveTranscodingCommand,
getLiveMuxingCommand,
convertWebPToJPG,
processGIF,
generateImageFromVideoFile,
TranscodeOptions,
TranscodeOptionsType,
transcode,
hlsPlaylistToFragmentedMP4
}
// ---------------------------------------------------------------------------
// ---------------------------------------------------------------------------
// Default options
// ---------------------------------------------------------------------------
function addEncoderDefaultParams (command: ffmpeg.FfmpegCommand, encoder: 'libx264' | string, fps?: number) {
if (encoder !== 'libx264') return
command.outputOption('-level 3.1') // 3.1 is the minimal resource allocation for our highest supported resolution
.outputOption('-b_strategy 1') // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it
.outputOption('-bf 16') // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16
.outputOption('-pix_fmt yuv420p') // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
.outputOption('-map_metadata -1') // strip all metadata
.outputOption('-max_muxing_queue_size 1024') // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375
// Keyframe interval of 2 seconds for faster seeking and resolution switching.
// https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
// https://superuser.com/a/908325
.outputOption('-g ' + (fps * 2))
}
function addDefaultLiveHLSParams (command: ffmpeg.FfmpegCommand, outPath: string, deleteSegments: boolean) {
command.outputOption('-hls_time ' + VIDEO_LIVE.SEGMENT_TIME_SECONDS)
command.outputOption('-hls_list_size ' + VIDEO_LIVE.SEGMENTS_LIST_SIZE)
if (deleteSegments === true) {
command.outputOption('-hls_flags delete_segments')
}
command.outputOption(`-hls_segment_filename ${join(outPath, '%v-%06d.ts')}`)
command.outputOption('-master_pl_name master.m3u8')
command.outputOption(`-f hls`)
command.output(join(outPath, '%v.m3u8'))
}
// ---------------------------------------------------------------------------
// Transcode VOD command builders
// ---------------------------------------------------------------------------
async function buildx264VODCommand (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) {
let fps = await getVideoFileFPS(options.inputPath)
if (
// On small/medium resolutions, limit FPS
options.resolution !== undefined &&
options.resolution < VIDEO_TRANSCODING_FPS.KEEP_ORIGIN_FPS_RESOLUTION_MIN &&
fps > VIDEO_TRANSCODING_FPS.AVERAGE
) {
// Get closest standard framerate by modulo: downsampling has to be done to a divisor of the nominal fps value
fps = getClosestFramerateStandard(fps, 'STANDARD')
}
command = await presetVideo(command, options.inputPath, options, fps)
if (options.resolution !== undefined) {
// '?x720' or '720x?' for example
const size = options.isPortraitMode === true ? `${options.resolution}x?` : `?x${options.resolution}`
command = command.size(size)
}
if (fps) {
// Hard FPS limits
if (fps > VIDEO_TRANSCODING_FPS.MAX) fps = getClosestFramerateStandard(fps, 'HD_STANDARD')
else if (fps < VIDEO_TRANSCODING_FPS.MIN) fps = VIDEO_TRANSCODING_FPS.MIN
command = command.withFPS(fps)
}
return command
}
async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) {
command = command.loop(undefined)
command = await presetVideo(command, options.audioPath, options)
/*
MAIN reference: https://slhck.info/video/2017/03/01/rate-control.html
Our target situation is closer to a livestream than a stream,
since we want to reduce as much a possible the encoding burden,
although not to the point of a livestream where there is a hard
constraint on the frames per second to be encoded.
*/
command.outputOption('-preset:v veryfast')
command = command.input(options.audioPath)
.videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error
.outputOption('-tune stillimage')
.outputOption('-shortest')
return command
}
function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, _options: OnlyAudioTranscodeOptions) {
command = presetOnlyAudio(command)
return command
}
function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) {
command = presetCopy(command)
command = command.outputOption('-map_metadata -1') // strip all metadata
.outputOption('-movflags faststart')
return command
}
async function buildHLSVODCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) {
const videoPath = getHLSVideoPath(options)
if (options.copyCodecs) command = presetCopy(command)
else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command)
else command = await buildx264VODCommand(command, options)
command = command.outputOption('-hls_time 4')
.outputOption('-hls_list_size 0')
.outputOption('-hls_playlist_type vod')
.outputOption('-hls_segment_filename ' + videoPath)
.outputOption('-hls_segment_type fmp4')
.outputOption('-f hls')
.outputOption('-hls_flags single_file')
return command
}
async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) {
if (options.type !== 'hls') return
const fileContent = await readFile(options.outputPath)
const videoFileName = options.hlsPlaylist.videoFilename
const videoFilePath = getHLSVideoPath(options)
// Fix wrong mapping with some ffmpeg versions
const newContent = fileContent.toString()
.replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`)
await writeFile(options.outputPath, newContent)
}
function getHLSVideoPath (options: HLSTranscodeOptions) {
return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}`
}
// ---------------------------------------------------------------------------
// Transcoding presets
// ---------------------------------------------------------------------------
async function presetVideo (
command: ffmpeg.FfmpegCommand,
input: string,
transcodeOptions: TranscodeOptions,
fps?: number
) {
let localCommand = command
.format('mp4')
.outputOption('-movflags faststart')
// Audio encoder
const parsedAudio = await getAudioStream(input)
let streamsToProcess = [ 'AUDIO', 'VIDEO' ]
const streamsFound = {
AUDIO: '',
VIDEO: ''
}
if (!parsedAudio.audioStream) {
localCommand = localCommand.noAudio()
streamsToProcess = [ 'VIDEO' ]
}
for (const stream of streamsToProcess) {
const encodersToTry: string[] = VIDEO_TRANSCODING_ENCODERS[stream]
for (const encoder of encodersToTry) {
if (!(await checkFFmpegEncoders()).get(encoder)) continue
const builderProfiles: EncoderProfile<EncoderOptionsBuilder> = transcodeOptions.availableEncoders.vod[encoder]
let builder = builderProfiles[transcodeOptions.profile]
if (!builder) {
logger.debug('Profile %s for encoder %s not available. Fallback to default.', transcodeOptions.profile, encoder)
builder = builderProfiles.default
}
const builderResult = await builder({ input, resolution: transcodeOptions.resolution, fps })
logger.debug('Apply ffmpeg params from %s.', encoder, builderResult)
localCommand.outputOptions(builderResult.outputOptions)
addEncoderDefaultParams(localCommand, encoder)
streamsFound[stream] = encoder
break
}
if (!streamsFound[stream]) {
throw new Error('No available encoder found ' + encodersToTry.join(', '))
}
}
localCommand.videoCodec(streamsFound.VIDEO)
return localCommand
}
function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
return command
.format('mp4')
.videoCodec('copy')
.audioCodec('copy')
}
function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand {
return command
.format('mp4')
.audioCodec('copy')
.noVideo()
}
// ---------------------------------------------------------------------------
// Utils
// ---------------------------------------------------------------------------
function getFFmpeg (input: string) {
// We set cwd explicitly because ffmpeg appears to create temporary files when trancoding which fails in read-only file systems
const command = ffmpeg(input, { niceness: FFMPEG_NICE.TRANSCODING, cwd: CONFIG.STORAGE.TMP_DIR })
if (CONFIG.TRANSCODING.THREADS > 0) {
// If we don't set any threads ffmpeg will chose automatically
command.outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
}
return command
}
async function runCommand (command: ffmpeg.FfmpegCommand, onEnd?: Function) {
return new Promise<void>((res, rej) => {
command.on('error', (err, stdout, stderr) => {
if (onEnd) onEnd()
logger.error('Error in transcoding job.', { stdout, stderr })
rej(err)
})
command.on('end', () => {
if (onEnd) onEnd()
res()
})
command.run()
})
}