import * as ffmpeg from 'fluent-ffmpeg' import { readFile, remove, writeFile } from 'fs-extra' import { dirname, join } from 'path' import { FFMPEG_NICE, VIDEO_LIVE, VIDEO_TRANSCODING_ENCODERS, VIDEO_TRANSCODING_FPS } from '@server/initializers/constants' import { VideoResolution } from '../../shared/models/videos' import { checkFFmpegEncoders } from '../initializers/checker-before-init' import { CONFIG } from '../initializers/config' import { getAudioStream, getClosestFramerateStandard, getVideoFileFPS } from './ffprobe-utils' import { processImage } from './image-utils' import { logger } from './logger' /** * * Functions that run transcoding/muxing ffmpeg processes * Mainly called by lib/video-transcoding.ts and lib/live-manager.ts * */ // --------------------------------------------------------------------------- // Encoder options // --------------------------------------------------------------------------- // Options builders export type EncoderOptionsBuilder = (params: { input: string resolution: VideoResolution fps?: number streamNum?: number }) => Promise | EncoderOptions // Options types export interface EncoderOptions { copy?: boolean outputOptions: string[] } // All our encoders export interface EncoderProfile { [ profile: string ]: T default: T } export type AvailableEncoders = { [ id in 'live' | 'vod' ]: { [ encoder in 'libx264' | 'aac' | 'libfdk_aac' ]?: EncoderProfile } } // --------------------------------------------------------------------------- // Image manipulation // --------------------------------------------------------------------------- function convertWebPToJPG (path: string, destination: string): Promise { const command = ffmpeg(path) .output(destination) return runCommand(command) } function processGIF ( path: string, destination: string, newSize: { width: number, height: number }, keepOriginal = false ): Promise { return new Promise(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((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 } = { '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 // --------------------------------------------------------------------------- async function getLiveTranscodingCommand (options: { rtmpUrl: string outPath: string resolutions: number[] fps: number deleteSegments: boolean availableEncoders: AvailableEncoders profile: string }) { const { rtmpUrl, outPath, resolutions, fps, deleteSegments, availableEncoders, profile } = options const input = rtmpUrl const command = getFFmpeg(input) 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}` })) ]) command.outputOption('-preset superfast') for (let i = 0; i < resolutions.length; i++) { const resolution = resolutions[i] const baseEncoderBuilderParams = { input, availableEncoders, profile, fps, resolution, streamNum: i, videoType: 'live' as 'live' } { const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'VIDEO' })) if (!builderResult) { throw new Error('No available live video encoder found') } command.outputOption(`-map [vout${resolution}]`) addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps, streamNum: i }) logger.debug('Apply ffmpeg live video params from %s.', builderResult.encoder, builderResult) command.outputOption(`${buildStreamSuffix('-c:v', i)} ${builderResult.encoder}`) command.addOutputOptions(builderResult.result.outputOptions) } { const builderResult = await getEncoderBuilderResult(Object.assign({}, baseEncoderBuilderParams, { streamType: 'AUDIO' })) if (!builderResult) { throw new Error('No available live audio encoder found') } command.outputOption('-map a:0') addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps, streamNum: i }) logger.debug('Apply ffmpeg live audio params from %s.', builderResult.encoder, builderResult) command.outputOption(`${buildStreamSuffix('-c:a', i)} ${builderResult.encoder}`) command.addOutputOptions(builderResult.result.outputOptions) } varStreamMap.push(`v:${i},a:${i}`) } addDefaultLiveHLSParams(command, outPath, deleteSegments) command.outputOption('-var_stream_map', varStreamMap.join(' ')) return command } function getLiveMuxingCommand (rtmpUrl: string, outPath: string, deleteSegments: boolean) { const command = getFFmpeg(rtmpUrl) command.inputOption('-fflags nobuffer') command.outputOption('-c:v copy') command.outputOption('-c:a copy') command.outputOption('-map 0:a?') command.outputOption('-map 0:v?') addDefaultLiveHLSParams(command, outPath, deleteSegments) return command } async function hlsPlaylistToFragmentedMP4 (hlsDirectory: string, segmentFiles: string[], outputPath: string) { const concatFilePath = join(hlsDirectory, 'concat.txt') function cleaner () { remove(concatFilePath) .catch(err => logger.error('Cannot remove concat file in %s.', hlsDirectory, { err })) } // First concat the ts files to a mp4 file const content = segmentFiles.map(f => 'file ' + f) .join('\n') await writeFile(concatFilePath, content + '\n') const command = getFFmpeg(concatFilePath) command.inputOption('-safe 0') command.inputOption('-f concat') command.outputOption('-c:v copy') command.audioFilter('aresample=async=1:first_pts=0') command.output(outputPath) return runCommand(command, cleaner) } function buildStreamSuffix (base: string, streamNum?: number) { if (streamNum !== undefined) { return `${base}:${streamNum}` } return base } // --------------------------------------------------------------------------- export { getLiveTranscodingCommand, getLiveMuxingCommand, buildStreamSuffix, convertWebPToJPG, processGIF, generateImageFromVideoFile, TranscodeOptions, TranscodeOptionsType, transcode, hlsPlaylistToFragmentedMP4 } // --------------------------------------------------------------------------- // --------------------------------------------------------------------------- // Default options // --------------------------------------------------------------------------- function addDefaultEncoderParams (options: { command: ffmpeg.FfmpegCommand encoder: 'libx264' | string streamNum?: number fps?: number }) { const { command, encoder, fps, streamNum } = options if (encoder === 'libx264') { // 3.1 is the minimal resource allocation for our highest supported resolution command.outputOption('-level 3.1') // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it .outputOption('-b_strategy 1') // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16 .outputOption('-bf 16') // allows import of source material with incompatible pixel formats (e.g. MJPEG video) .outputOption(buildStreamSuffix('-pix_fmt', streamNum) + ' yuv420p') // strip all metadata .outputOption('-map_metadata -1') // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375 .outputOption(buildStreamSuffix('-max_muxing_queue_size', streamNum) + ' 1024') if (fps) { // 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 command.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) } // 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 getEncoderBuilderResult (options: { streamType: string input: string availableEncoders: AvailableEncoders profile: string videoType: 'vod' | 'live' resolution: number fps?: number streamNum?: number }) { const { availableEncoders, input, profile, resolution, streamType, fps, streamNum, videoType } = options const encodersToTry: string[] = VIDEO_TRANSCODING_ENCODERS[streamType] for (const encoder of encodersToTry) { if (!(await checkFFmpegEncoders()).get(encoder) || !availableEncoders[videoType][encoder]) continue const builderProfiles: EncoderProfile = availableEncoders[videoType][encoder] let builder = builderProfiles[profile] if (!builder) { logger.debug('Profile %s for encoder %s not available. Fallback to default.', profile, encoder) builder = builderProfiles.default } const result = await builder({ input, resolution: resolution, fps, streamNum }) return { result, // If we don't have output options, then copy the input stream encoder: result.copy === true ? 'copy' : encoder } } return null } 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' ] if (!parsedAudio.audioStream) { localCommand = localCommand.noAudio() streamsToProcess = [ 'VIDEO' ] } for (const streamType of streamsToProcess) { const { profile, resolution, availableEncoders } = transcodeOptions const builderResult = await getEncoderBuilderResult({ streamType, input, resolution, availableEncoders, profile, fps, videoType: 'vod' as 'vod' }) if (!builderResult) { throw new Error('No available encoder found for stream ' + streamType) } logger.debug('Apply ffmpeg params from %s.', builderResult.encoder, builderResult) if (streamType === 'VIDEO') { localCommand.videoCodec(builderResult.encoder) } else if (streamType === 'AUDIO') { localCommand.audioCodec(builderResult.encoder) } command.addOutputOptions(builderResult.result.outputOptions) addDefaultEncoderParams({ command: localCommand, encoder: builderResult.encoder, fps }) } 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((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() }) }