import * as ffmpeg from 'fluent-ffmpeg'
import { join } from 'path'
-import { VideoResolution } from '../../shared/models/videos'
-import { CONFIG, VIDEO_TRANSCODING_FPS } from '../initializers'
-import { unlinkPromise } from './core-utils'
+import { getTargetBitrate, VideoResolution } from '../../shared/models/videos'
+import { CONFIG, FFMPEG_NICE, VIDEO_TRANSCODING_FPS } from '../initializers/constants'
import { processImage } from './image-utils'
import { logger } from './logger'
+import { checkFFmpegEncoders } from '../initializers/checker-before-init'
+import { remove } from 'fs-extra'
+
+function computeResolutionsToTranscode (videoFileHeight: number) {
+ const resolutionsEnabled: number[] = []
+ const configResolutions = CONFIG.TRANSCODING.RESOLUTIONS
+
+ // Put in the order we want to proceed jobs
+ const resolutions = [
+ VideoResolution.H_480P,
+ VideoResolution.H_360P,
+ VideoResolution.H_720P,
+ VideoResolution.H_240P,
+ VideoResolution.H_1080P
+ ]
+
+ for (const resolution of resolutions) {
+ if (configResolutions[ resolution + 'p' ] === true && videoFileHeight > resolution) {
+ resolutionsEnabled.push(resolution)
+ }
+ }
+
+ return resolutionsEnabled
+}
async function getVideoFileResolution (path: string) {
const videoStream = await getVideoFileStream(path)
if (!frames || !seconds) continue
const result = parseInt(frames, 10) / parseInt(seconds, 10)
- if (result > 0) return result
+ if (result > 0) return Math.round(result)
}
return 0
}
+async function getVideoFileBitrate (path: string) {
+ return new Promise<number>((res, rej) => {
+ ffmpeg.ffprobe(path, (err, metadata) => {
+ if (err) return rej(err)
+
+ return res(metadata.format.bit_rate)
+ })
+ })
+}
+
function getDurationFromVideoFile (path: string) {
return new Promise<number>((res, rej) => {
ffmpeg.ffprobe(path, (err, metadata) => {
try {
await new Promise<string>((res, rej) => {
- ffmpeg(fromPath)
+ ffmpeg(fromPath, { niceness: FFMPEG_NICE.THUMBNAIL })
.on('error', rej)
.on('end', () => res(imageName))
.thumbnail(options)
logger.error('Cannot generate image from video %s.', fromPath, { err })
try {
- await unlinkPromise(pendingImagePath)
+ await remove(pendingImagePath)
} catch (err) {
logger.debug('Cannot remove pending image path after generation error.', { err })
}
function transcode (options: TranscodeOptions) {
return new Promise<void>(async (res, rej) => {
- const fps = await getVideoFileFPS(options.inputPath)
-
- let command = ffmpeg(options.inputPath)
- .output(options.outputPath)
- .videoCodec('libx264')
- .outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
- .outputOption('-movflags faststart')
- // .outputOption('-crf 18')
-
- // Our player has some FPS limits
- if (fps > VIDEO_TRANSCODING_FPS.MAX) command = command.withFPS(VIDEO_TRANSCODING_FPS.MAX)
- else if (fps < VIDEO_TRANSCODING_FPS.MIN) command = command.withFPS(VIDEO_TRANSCODING_FPS.MIN)
-
- if (options.resolution !== undefined) {
- // '?x720' or '720x?' for example
- const size = options.isPortraitMode === true ? `${options.resolution}x?` : `?x${options.resolution}`
- command = command.size(size)
- }
+ try {
+ let fps = await getVideoFileFPS(options.inputPath)
+ // On small/medium resolutions, limit FPS
+ if (
+ options.resolution !== undefined &&
+ options.resolution < VIDEO_TRANSCODING_FPS.KEEP_ORIGIN_FPS_RESOLUTION_MIN &&
+ fps > VIDEO_TRANSCODING_FPS.AVERAGE
+ ) {
+ fps = VIDEO_TRANSCODING_FPS.AVERAGE
+ }
+
+ let command = ffmpeg(options.inputPath, { niceness: FFMPEG_NICE.TRANSCODING })
+ .output(options.outputPath)
+ command = await presetH264(command, options.resolution, fps)
+
+ if (CONFIG.TRANSCODING.THREADS > 0) {
+ // if we don't set any threads ffmpeg will chose automatically
+ command = command.outputOption('-threads ' + CONFIG.TRANSCODING.THREADS)
+ }
+
+ 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 = VIDEO_TRANSCODING_FPS.MAX
+ else if (fps < VIDEO_TRANSCODING_FPS.MIN) fps = VIDEO_TRANSCODING_FPS.MIN
+
+ command = command.withFPS(fps)
+ }
- command
- .on('error', (err, stdout, stderr) => {
- logger.error('Error in transcoding job.', { stdout, stderr })
- return rej(err)
- })
- .on('end', res)
- .run()
+ command
+ .on('error', (err, stdout, stderr) => {
+ logger.error('Error in transcoding job.', { stdout, stderr })
+ return rej(err)
+ })
+ .on('end', res)
+ .run()
+ } catch (err) {
+ return rej(err)
+ }
})
}
getDurationFromVideoFile,
generateImageFromVideoFile,
transcode,
- getVideoFileFPS
+ getVideoFileFPS,
+ computeResolutionsToTranscode,
+ audio,
+ getVideoFileBitrate
}
// ---------------------------------------------------------------------------
if (err) return rej(err)
const videoStream = metadata.streams.find(s => s.codec_type === 'video')
- if (!videoStream) throw new Error('Cannot find video stream of ' + path)
+ if (!videoStream) return rej(new Error('Cannot find video stream of ' + path))
return res(videoStream)
})
})
}
+
+/**
+ * A slightly customised version of the 'veryfast' x264 preset
+ *
+ * The veryfast preset is right in the sweet spot of performance
+ * and quality. Superfast and ultrafast will give you better
+ * performance, but then quality is noticeably worse.
+ */
+async function presetH264VeryFast (command: ffmpeg.FfmpegCommand, resolution: VideoResolution, fps: number): Promise<ffmpeg.FfmpegCommand> {
+ let localCommand = await presetH264(command, resolution, fps)
+ localCommand = localCommand.outputOption('-preset:v veryfast')
+ .outputOption([ '--aq-mode=2', '--aq-strength=1.3' ])
+ /*
+ 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,
+ altough not to the point of a livestream where there is a hard
+ constraint on the frames per second to be encoded.
+
+ why '--aq-mode=2 --aq-strength=1.3' instead of '-profile:v main'?
+ Make up for most of the loss of grain and macroblocking
+ with less computing power.
+ */
+
+ return localCommand
+}
+
+/**
+ * A preset optimised for a stillimage audio video
+ */
+async function presetStillImageWithAudio (
+ command: ffmpeg.FfmpegCommand,
+ resolution: VideoResolution,
+ fps: number
+): Promise<ffmpeg.FfmpegCommand> {
+ let localCommand = await presetH264VeryFast(command, resolution, fps)
+ localCommand = localCommand.outputOption('-tune stillimage')
+
+ return localCommand
+}
+
+/**
+ * A toolbox to play with audio
+ */
+namespace audio {
+ export const get = (option: ffmpeg.FfmpegCommand | string) => {
+ // without position, ffprobe considers the last input only
+ // we make it consider the first input only
+ // if you pass a file path to pos, then ffprobe acts on that file directly
+ return new Promise<{ absolutePath: string, audioStream?: any }>((res, rej) => {
+
+ function parseFfprobe (err: any, data: ffmpeg.FfprobeData) {
+ if (err) return rej(err)
+
+ if ('streams' in data) {
+ const audioStream = data.streams.find(stream => stream['codec_type'] === 'audio')
+ if (audioStream) {
+ return res({
+ absolutePath: data.format.filename,
+ audioStream
+ })
+ }
+ }
+
+ return res({ absolutePath: data.format.filename })
+ }
+
+ if (typeof option === 'string') {
+ return ffmpeg.ffprobe(option, parseFfprobe)
+ }
+
+ return option.ffprobe(parseFfprobe)
+ })
+ }
+
+ export namespace bitrate {
+ const baseKbitrate = 384
+
+ const toBits = (kbits: number): number => { return kbits * 8000 }
+
+ export const aac = (bitrate: number): number => {
+ switch (true) {
+ case bitrate > toBits(baseKbitrate):
+ return baseKbitrate
+ default:
+ return -1 // we interpret it as a signal to copy the audio stream as is
+ }
+ }
+
+ export const mp3 = (bitrate: number): number => {
+ /*
+ a 192kbit/sec mp3 doesn't hold as much information as a 192kbit/sec aac.
+ That's why, when using aac, we can go to lower kbit/sec. The equivalences
+ made here are not made to be accurate, especially with good mp3 encoders.
+ */
+ switch (true) {
+ case bitrate <= toBits(192):
+ return 128
+ case bitrate <= toBits(384):
+ return 256
+ default:
+ return baseKbitrate
+ }
+ }
+ }
+}
+
+/**
+ * Standard profile, with variable bitrate audio and faststart.
+ *
+ * As for the audio, quality '5' is the highest and ensures 96-112kbps/channel
+ * See https://trac.ffmpeg.org/wiki/Encode/AAC#fdk_vbr
+ */
+async function presetH264 (command: ffmpeg.FfmpegCommand, resolution: VideoResolution, fps: number): Promise<ffmpeg.FfmpegCommand> {
+ let localCommand = command
+ .format('mp4')
+ .videoCodec('libx264')
+ .outputOption('-level 3.1') // 3.1 is the minimal ressource allocation for our highest supported resolution
+ .outputOption('-b_strategy 1') // NOTE: b-strategy 1 - heuristic algorythm, 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('-movflags faststart')
+
+ const parsedAudio = await audio.get(localCommand)
+
+ if (!parsedAudio.audioStream) {
+ localCommand = localCommand.noAudio()
+ } else if ((await checkFFmpegEncoders()).get('libfdk_aac')) { // we favor VBR, if a good AAC encoder is available
+ localCommand = localCommand
+ .audioCodec('libfdk_aac')
+ .audioQuality(5)
+ } else {
+ // we try to reduce the ceiling bitrate by making rough correspondances of bitrates
+ // of course this is far from perfect, but it might save some space in the end
+ const audioCodecName = parsedAudio.audioStream[ 'codec_name' ]
+ let bitrate: number
+ if (audio.bitrate[ audioCodecName ]) {
+ localCommand = localCommand.audioCodec('aac')
+
+ bitrate = audio.bitrate[ audioCodecName ](parsedAudio.audioStream[ 'bit_rate' ])
+ if (bitrate !== undefined && bitrate !== -1) localCommand = localCommand.audioBitrate(bitrate)
+ }
+ }
+
+ // Constrained Encoding (VBV)
+ // https://slhck.info/video/2017/03/01/rate-control.html
+ // https://trac.ffmpeg.org/wiki/Limiting%20the%20output%20bitrate
+ const targetBitrate = getTargetBitrate(resolution, fps, VIDEO_TRANSCODING_FPS)
+ localCommand = localCommand.outputOptions([`-maxrate ${ targetBitrate }`, `-bufsize ${ targetBitrate * 2 }`])
+
+ // 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
+ localCommand = localCommand.outputOption(`-g ${ fps * 2 }`)
+
+ return localCommand
+}