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Commit | Line | Data |
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14d3270f | 1 | import * as ffmpeg from 'fluent-ffmpeg' |
09209296 | 2 | import { dirname, join } from 'path' |
a1587156 | 3 | import { getMaxBitrate, getTargetBitrate, VideoResolution } from '../../shared/models/videos' |
6dd9de95 | 4 | import { FFMPEG_NICE, VIDEO_TRANSCODING_FPS } from '../initializers/constants' |
26670720 | 5 | import { processImage } from './image-utils' |
6fdc553a | 6 | import { logger } from './logger' |
e5565833 | 7 | import { checkFFmpegEncoders } from '../initializers/checker-before-init' |
6dd9de95 C |
8 | import { readFile, remove, writeFile } from 'fs-extra' |
9 | import { CONFIG } from '../initializers/config' | |
8319d6ae | 10 | import { VideoFileMetadata } from '@shared/models/videos/video-file-metadata' |
14d3270f | 11 | |
a1587156 C |
12 | /** |
13 | * A toolbox to play with audio | |
14 | */ | |
15 | namespace 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) => { | |
21 | ||
22 | function parseFfprobe (err: any, data: ffmpeg.FfprobeData) { | |
23 | if (err) return rej(err) | |
24 | ||
25 | if ('streams' in data) { | |
26 | const audioStream = data.streams.find(stream => stream['codec_type'] === 'audio') | |
27 | if (audioStream) { | |
28 | return res({ | |
29 | absolutePath: data.format.filename, | |
30 | audioStream | |
31 | }) | |
32 | } | |
33 | } | |
34 | ||
35 | return res({ absolutePath: data.format.filename }) | |
36 | } | |
37 | ||
38 | return ffmpeg.ffprobe(videoPath, parseFfprobe) | |
39 | }) | |
40 | } | |
41 | ||
42 | export namespace bitrate { | |
43 | const baseKbitrate = 384 | |
44 | ||
45 | const toBits = (kbits: number) => kbits * 8000 | |
46 | ||
47 | export const aac = (bitrate: number): number => { | |
48 | switch (true) { | |
49 | case bitrate > toBits(baseKbitrate): | |
50 | return baseKbitrate | |
51 | ||
52 | default: | |
53 | return -1 // we interpret it as a signal to copy the audio stream as is | |
54 | } | |
55 | } | |
56 | ||
57 | export const mp3 = (bitrate: number): number => { | |
58 | /* | |
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. | |
62 | */ | |
63 | switch (true) { | |
64 | case bitrate <= toBits(192): | |
65 | return 128 | |
66 | ||
67 | case bitrate <= toBits(384): | |
68 | return 256 | |
69 | ||
70 | default: | |
71 | return baseKbitrate | |
72 | } | |
73 | } | |
74 | } | |
75 | } | |
76 | ||
06215f15 C |
77 | function computeResolutionsToTranscode (videoFileHeight: number) { |
78 | const resolutionsEnabled: number[] = [] | |
79 | const configResolutions = CONFIG.TRANSCODING.RESOLUTIONS | |
80 | ||
81 | // Put in the order we want to proceed jobs | |
82 | const resolutions = [ | |
5c7d6508 | 83 | VideoResolution.H_NOVIDEO, |
06215f15 C |
84 | VideoResolution.H_480P, |
85 | VideoResolution.H_360P, | |
86 | VideoResolution.H_720P, | |
87 | VideoResolution.H_240P, | |
ad3405d0 C |
88 | VideoResolution.H_1080P, |
89 | VideoResolution.H_4K | |
06215f15 C |
90 | ] |
91 | ||
92 | for (const resolution of resolutions) { | |
a1587156 | 93 | if (configResolutions[resolution + 'p'] === true && videoFileHeight > resolution) { |
06215f15 C |
94 | resolutionsEnabled.push(resolution) |
95 | } | |
96 | } | |
97 | ||
98 | return resolutionsEnabled | |
99 | } | |
100 | ||
52201311 | 101 | async function getVideoStreamSize (path: string) { |
5ba49f26 | 102 | const videoStream = await getVideoStreamFromFile(path) |
056aa7f2 | 103 | |
3a149e9f C |
104 | return videoStream === null |
105 | ? { width: 0, height: 0 } | |
106 | : { width: videoStream.width, height: videoStream.height } | |
09209296 C |
107 | } |
108 | ||
52201311 C |
109 | async function getVideoStreamCodec (path: string) { |
110 | const videoStream = await getVideoStreamFromFile(path) | |
111 | ||
112 | if (!videoStream) return '' | |
113 | ||
114 | const videoCodec = videoStream.codec_tag_string | |
115 | ||
116 | const baseProfileMatrix = { | |
a1587156 C |
117 | High: '6400', |
118 | Main: '4D40', | |
119 | Baseline: '42E0' | |
52201311 C |
120 | } |
121 | ||
122 | let baseProfile = baseProfileMatrix[videoStream.profile] | |
123 | if (!baseProfile) { | |
124 | logger.warn('Cannot get video profile codec of %s.', path, { videoStream }) | |
125 | baseProfile = baseProfileMatrix['High'] // Fallback | |
126 | } | |
127 | ||
a2b6ec7c C |
128 | let level = videoStream.level.toString(16) |
129 | if (level.length === 1) level = `0${level}` | |
52201311 C |
130 | |
131 | return `${videoCodec}.${baseProfile}${level}` | |
132 | } | |
133 | ||
134 | async function getAudioStreamCodec (path: string) { | |
135 | const { audioStream } = await audio.get(path) | |
136 | ||
137 | if (!audioStream) return '' | |
138 | ||
139 | const audioCodec = audioStream.codec_name | |
49c3bf6f | 140 | if (audioCodec === 'aac') return 'mp4a.40.2' |
52201311 C |
141 | |
142 | logger.warn('Cannot get audio codec of %s.', path, { audioStream }) | |
143 | ||
144 | return 'mp4a.40.2' // Fallback | |
145 | } | |
146 | ||
09209296 | 147 | async function getVideoFileResolution (path: string) { |
52201311 | 148 | const size = await getVideoStreamSize(path) |
09209296 C |
149 | |
150 | return { | |
151 | videoFileResolution: Math.min(size.height, size.width), | |
152 | isPortraitMode: size.height > size.width | |
056aa7f2 | 153 | } |
73c69591 | 154 | } |
14d3270f | 155 | |
73c69591 | 156 | async function getVideoFileFPS (path: string) { |
5ba49f26 | 157 | const videoStream = await getVideoStreamFromFile(path) |
3a149e9f | 158 | if (videoStream === null) return 0 |
5c7d6508 | 159 | |
ef04ae20 | 160 | for (const key of [ 'avg_frame_rate', 'r_frame_rate' ]) { |
a1587156 | 161 | const valuesText: string = videoStream[key] |
73c69591 C |
162 | if (!valuesText) continue |
163 | ||
164 | const [ frames, seconds ] = valuesText.split('/') | |
165 | if (!frames || !seconds) continue | |
166 | ||
167 | const result = parseInt(frames, 10) / parseInt(seconds, 10) | |
3a6f351b | 168 | if (result > 0) return Math.round(result) |
73c69591 C |
169 | } |
170 | ||
171 | return 0 | |
14d3270f C |
172 | } |
173 | ||
7b81edc8 | 174 | async function getMetadataFromFile <T> (path: string, cb = metadata => metadata) { |
8319d6ae | 175 | return new Promise<T>((res, rej) => { |
edb4ffc7 FA |
176 | ffmpeg.ffprobe(path, (err, metadata) => { |
177 | if (err) return rej(err) | |
178 | ||
8319d6ae | 179 | return res(cb(new VideoFileMetadata(metadata))) |
edb4ffc7 FA |
180 | }) |
181 | }) | |
182 | } | |
183 | ||
8319d6ae RK |
184 | async function getVideoFileBitrate (path: string) { |
185 | return getMetadataFromFile<number>(path, metadata => metadata.format.bit_rate) | |
186 | } | |
187 | ||
14d3270f | 188 | function getDurationFromVideoFile (path: string) { |
8319d6ae RK |
189 | return getMetadataFromFile<number>(path, metadata => Math.floor(metadata.format.duration)) |
190 | } | |
14d3270f | 191 | |
8319d6ae RK |
192 | function getVideoStreamFromFile (path: string) { |
193 | return getMetadataFromFile<any>(path, metadata => metadata.streams.find(s => s.codec_type === 'video') || null) | |
14d3270f C |
194 | } |
195 | ||
26670720 C |
196 | async function generateImageFromVideoFile (fromPath: string, folder: string, imageName: string, size: { width: number, height: number }) { |
197 | const pendingImageName = 'pending-' + imageName | |
198 | ||
14d3270f | 199 | const options = { |
26670720 | 200 | filename: pendingImageName, |
14d3270f C |
201 | count: 1, |
202 | folder | |
203 | } | |
204 | ||
26670720 | 205 | const pendingImagePath = join(folder, pendingImageName) |
6fdc553a C |
206 | |
207 | try { | |
208 | await new Promise<string>((res, rej) => { | |
7160878c | 209 | ffmpeg(fromPath, { niceness: FFMPEG_NICE.THUMBNAIL }) |
6fdc553a C |
210 | .on('error', rej) |
211 | .on('end', () => res(imageName)) | |
212 | .thumbnail(options) | |
213 | }) | |
214 | ||
215 | const destination = join(folder, imageName) | |
2fb5b3a5 | 216 | await processImage(pendingImagePath, destination, size) |
6fdc553a | 217 | } catch (err) { |
d5b7d911 | 218 | logger.error('Cannot generate image from video %s.', fromPath, { err }) |
6fdc553a C |
219 | |
220 | try { | |
62689b94 | 221 | await remove(pendingImagePath) |
6fdc553a | 222 | } catch (err) { |
d5b7d911 | 223 | logger.debug('Cannot remove pending image path after generation error.', { err }) |
6fdc553a C |
224 | } |
225 | } | |
14d3270f C |
226 | } |
227 | ||
3a149e9f | 228 | type TranscodeOptionsType = 'hls' | 'quick-transcode' | 'video' | 'merge-audio' | 'only-audio' |
536598cf C |
229 | |
230 | interface BaseTranscodeOptions { | |
231 | type: TranscodeOptionsType | |
14d3270f C |
232 | inputPath: string |
233 | outputPath: string | |
09209296 | 234 | resolution: VideoResolution |
056aa7f2 | 235 | isPortraitMode?: boolean |
536598cf | 236 | } |
09209296 | 237 | |
536598cf C |
238 | interface HLSTranscodeOptions extends BaseTranscodeOptions { |
239 | type: 'hls' | |
d7a25329 | 240 | copyCodecs: boolean |
536598cf | 241 | hlsPlaylist: { |
4c280004 C |
242 | videoFilename: string |
243 | } | |
14d3270f C |
244 | } |
245 | ||
536598cf C |
246 | interface QuickTranscodeOptions extends BaseTranscodeOptions { |
247 | type: 'quick-transcode' | |
248 | } | |
249 | ||
250 | interface VideoTranscodeOptions extends BaseTranscodeOptions { | |
251 | type: 'video' | |
252 | } | |
253 | ||
254 | interface MergeAudioTranscodeOptions extends BaseTranscodeOptions { | |
255 | type: 'merge-audio' | |
256 | audioPath: string | |
257 | } | |
258 | ||
3a149e9f C |
259 | interface OnlyAudioTranscodeOptions extends BaseTranscodeOptions { |
260 | type: 'only-audio' | |
5c7d6508 | 261 | } |
262 | ||
a1587156 C |
263 | type TranscodeOptions = |
264 | HLSTranscodeOptions | |
3a149e9f C |
265 | | VideoTranscodeOptions |
266 | | MergeAudioTranscodeOptions | |
267 | | OnlyAudioTranscodeOptions | |
268 | | QuickTranscodeOptions | |
536598cf | 269 | |
14d3270f | 270 | function transcode (options: TranscodeOptions) { |
73c69591 | 271 | return new Promise<void>(async (res, rej) => { |
cdf4cb9e | 272 | try { |
cdf4cb9e C |
273 | let command = ffmpeg(options.inputPath, { niceness: FFMPEG_NICE.TRANSCODING }) |
274 | .output(options.outputPath) | |
14aed608 | 275 | |
536598cf | 276 | if (options.type === 'quick-transcode') { |
a1587156 | 277 | command = buildQuickTranscodeCommand(command) |
536598cf | 278 | } else if (options.type === 'hls') { |
14aed608 | 279 | command = await buildHLSCommand(command, options) |
536598cf C |
280 | } else if (options.type === 'merge-audio') { |
281 | command = await buildAudioMergeCommand(command, options) | |
3a149e9f | 282 | } else if (options.type === 'only-audio') { |
a1587156 | 283 | command = buildOnlyAudioCommand(command, options) |
14aed608 C |
284 | } else { |
285 | command = await buildx264Command(command, options) | |
286 | } | |
7160878c | 287 | |
cdf4cb9e C |
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) | |
291 | } | |
14d3270f | 292 | |
cdf4cb9e C |
293 | command |
294 | .on('error', (err, stdout, stderr) => { | |
295 | logger.error('Error in transcoding job.', { stdout, stderr }) | |
296 | return rej(err) | |
297 | }) | |
7f8f8bdb | 298 | .on('end', () => { |
536598cf | 299 | return fixHLSPlaylistIfNeeded(options) |
7f8f8bdb C |
300 | .then(() => res()) |
301 | .catch(err => rej(err)) | |
302 | }) | |
cdf4cb9e C |
303 | .run() |
304 | } catch (err) { | |
305 | return rej(err) | |
306 | } | |
14d3270f C |
307 | }) |
308 | } | |
309 | ||
7ed2c1a4 | 310 | async function canDoQuickTranscode (path: string): Promise<boolean> { |
5ba49f26 FA |
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) | |
317 | ||
318 | // check video params | |
5c7d6508 | 319 | if (videoStream == null) return false |
a1587156 C |
320 | if (videoStream['codec_name'] !== 'h264') return false |
321 | if (videoStream['pix_fmt'] !== 'yuv420p') return false | |
1600235a C |
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 | |
5ba49f26 | 324 | |
3a149e9f | 325 | // check audio params (if audio stream exists) |
5ba49f26 | 326 | if (parsedAudio.audioStream) { |
a1587156 | 327 | if (parsedAudio.audioStream['codec_name'] !== 'aac') return false |
1600235a | 328 | |
a1587156 C |
329 | const maxAudioBitrate = audio.bitrate['aac'](parsedAudio.audioStream['bit_rate']) |
330 | if (maxAudioBitrate !== -1 && parsedAudio.audioStream['bit_rate'] > maxAudioBitrate) return false | |
5ba49f26 | 331 | } |
7ed2c1a4 | 332 | |
5ba49f26 FA |
333 | return true |
334 | } | |
335 | ||
c7f36e4f C |
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] | |
837666fe RK |
339 | } |
340 | ||
14d3270f C |
341 | // --------------------------------------------------------------------------- |
342 | ||
343 | export { | |
52201311 C |
344 | getVideoStreamCodec, |
345 | getAudioStreamCodec, | |
346 | getVideoStreamSize, | |
056aa7f2 | 347 | getVideoFileResolution, |
8319d6ae | 348 | getMetadataFromFile, |
14d3270f C |
349 | getDurationFromVideoFile, |
350 | generateImageFromVideoFile, | |
536598cf C |
351 | TranscodeOptions, |
352 | TranscodeOptionsType, | |
73c69591 | 353 | transcode, |
7160878c | 354 | getVideoFileFPS, |
06215f15 | 355 | computeResolutionsToTranscode, |
edb4ffc7 | 356 | audio, |
5ba49f26 FA |
357 | getVideoFileBitrate, |
358 | canDoQuickTranscode | |
73c69591 C |
359 | } |
360 | ||
361 | // --------------------------------------------------------------------------- | |
362 | ||
d7a25329 | 363 | async function buildx264Command (command: ffmpeg.FfmpegCommand, options: TranscodeOptions) { |
14aed608 | 364 | let fps = await getVideoFileFPS(options.inputPath) |
14aed608 | 365 | if ( |
06bcfbd9 | 366 | // On small/medium resolutions, limit FPS |
14aed608 C |
367 | options.resolution !== undefined && |
368 | options.resolution < VIDEO_TRANSCODING_FPS.KEEP_ORIGIN_FPS_RESOLUTION_MIN && | |
c7f36e4f | 369 | fps > VIDEO_TRANSCODING_FPS.AVERAGE |
14aed608 | 370 | ) { |
06bcfbd9 | 371 | // Get closest standard framerate by modulo: downsampling has to be done to a divisor of the nominal fps value |
c7f36e4f | 372 | fps = getClosestFramerateStandard(fps, 'STANDARD') |
14aed608 C |
373 | } |
374 | ||
536598cf | 375 | command = await presetH264(command, options.inputPath, options.resolution, fps) |
14aed608 C |
376 | |
377 | if (options.resolution !== undefined) { | |
378 | // '?x720' or '720x?' for example | |
379 | const size = options.isPortraitMode === true ? `${options.resolution}x?` : `?x${options.resolution}` | |
380 | command = command.size(size) | |
381 | } | |
382 | ||
383 | if (fps) { | |
384 | // Hard FPS limits | |
c7f36e4f | 385 | if (fps > VIDEO_TRANSCODING_FPS.MAX) fps = getClosestFramerateStandard(fps, 'HD_STANDARD') |
14aed608 C |
386 | else if (fps < VIDEO_TRANSCODING_FPS.MIN) fps = VIDEO_TRANSCODING_FPS.MIN |
387 | ||
388 | command = command.withFPS(fps) | |
389 | } | |
390 | ||
391 | return command | |
392 | } | |
393 | ||
536598cf C |
394 | async function buildAudioMergeCommand (command: ffmpeg.FfmpegCommand, options: MergeAudioTranscodeOptions) { |
395 | command = command.loop(undefined) | |
396 | ||
397 | command = await presetH264VeryFast(command, options.audioPath, options.resolution) | |
398 | ||
399 | command = command.input(options.audioPath) | |
400 | .videoFilter('scale=trunc(iw/2)*2:trunc(ih/2)*2') // Avoid "height not divisible by 2" error | |
401 | .outputOption('-tune stillimage') | |
402 | .outputOption('-shortest') | |
403 | ||
404 | return command | |
405 | } | |
406 | ||
a1587156 C |
407 | function buildOnlyAudioCommand (command: ffmpeg.FfmpegCommand, options: OnlyAudioTranscodeOptions) { |
408 | command = presetOnlyAudio(command) | |
5c7d6508 | 409 | |
410 | return command | |
411 | } | |
412 | ||
a1587156 C |
413 | function buildQuickTranscodeCommand (command: ffmpeg.FfmpegCommand) { |
414 | command = presetCopy(command) | |
536598cf C |
415 | |
416 | command = command.outputOption('-map_metadata -1') // strip all metadata | |
417 | .outputOption('-movflags faststart') | |
418 | ||
419 | return command | |
420 | } | |
421 | ||
422 | async function buildHLSCommand (command: ffmpeg.FfmpegCommand, options: HLSTranscodeOptions) { | |
14aed608 C |
423 | const videoPath = getHLSVideoPath(options) |
424 | ||
a1587156 | 425 | if (options.copyCodecs) command = presetCopy(command) |
1c320673 | 426 | else if (options.resolution === VideoResolution.H_NOVIDEO) command = presetOnlyAudio(command) |
d7a25329 | 427 | else command = await buildx264Command(command, options) |
14aed608 C |
428 | |
429 | command = command.outputOption('-hls_time 4') | |
430 | .outputOption('-hls_list_size 0') | |
431 | .outputOption('-hls_playlist_type vod') | |
432 | .outputOption('-hls_segment_filename ' + videoPath) | |
433 | .outputOption('-hls_segment_type fmp4') | |
434 | .outputOption('-f hls') | |
435 | .outputOption('-hls_flags single_file') | |
436 | ||
437 | return command | |
438 | } | |
439 | ||
536598cf | 440 | function getHLSVideoPath (options: HLSTranscodeOptions) { |
7f8f8bdb C |
441 | return `${dirname(options.outputPath)}/${options.hlsPlaylist.videoFilename}` |
442 | } | |
443 | ||
536598cf C |
444 | async function fixHLSPlaylistIfNeeded (options: TranscodeOptions) { |
445 | if (options.type !== 'hls') return | |
7f8f8bdb | 446 | |
7f8f8bdb C |
447 | const fileContent = await readFile(options.outputPath) |
448 | ||
449 | const videoFileName = options.hlsPlaylist.videoFilename | |
450 | const videoFilePath = getHLSVideoPath(options) | |
451 | ||
536598cf | 452 | // Fix wrong mapping with some ffmpeg versions |
7f8f8bdb C |
453 | const newContent = fileContent.toString() |
454 | .replace(`#EXT-X-MAP:URI="${videoFilePath}",`, `#EXT-X-MAP:URI="${videoFileName}",`) | |
455 | ||
456 | await writeFile(options.outputPath, newContent) | |
457 | } | |
458 | ||
4176e227 RK |
459 | /** |
460 | * A slightly customised version of the 'veryfast' x264 preset | |
461 | * | |
462 | * The veryfast preset is right in the sweet spot of performance | |
463 | * and quality. Superfast and ultrafast will give you better | |
464 | * performance, but then quality is noticeably worse. | |
465 | */ | |
536598cf C |
466 | async function presetH264VeryFast (command: ffmpeg.FfmpegCommand, input: string, resolution: VideoResolution, fps?: number) { |
467 | let localCommand = await presetH264(command, input, resolution, fps) | |
468 | ||
cdf4cb9e | 469 | localCommand = localCommand.outputOption('-preset:v veryfast') |
536598cf | 470 | |
4176e227 RK |
471 | /* |
472 | MAIN reference: https://slhck.info/video/2017/03/01/rate-control.html | |
473 | Our target situation is closer to a livestream than a stream, | |
474 | since we want to reduce as much a possible the encoding burden, | |
536598cf | 475 | although not to the point of a livestream where there is a hard |
4176e227 | 476 | constraint on the frames per second to be encoded. |
4176e227 | 477 | */ |
cdf4cb9e C |
478 | |
479 | return localCommand | |
4176e227 RK |
480 | } |
481 | ||
4176e227 RK |
482 | /** |
483 | * Standard profile, with variable bitrate audio and faststart. | |
484 | * | |
485 | * As for the audio, quality '5' is the highest and ensures 96-112kbps/channel | |
486 | * See https://trac.ffmpeg.org/wiki/Encode/AAC#fdk_vbr | |
487 | */ | |
536598cf | 488 | async function presetH264 (command: ffmpeg.FfmpegCommand, input: string, resolution: VideoResolution, fps?: number) { |
cdf4cb9e | 489 | let localCommand = command |
4176e227 RK |
490 | .format('mp4') |
491 | .videoCodec('libx264') | |
52201311 C |
492 | .outputOption('-level 3.1') // 3.1 is the minimal resource allocation for our highest supported resolution |
493 | .outputOption('-b_strategy 1') // NOTE: b-strategy 1 - heuristic algorithm, 16 is optimal B-frames for it | |
4176e227 | 494 | .outputOption('-bf 16') // NOTE: Why 16: https://github.com/Chocobozzz/PeerTube/pull/774. b-strategy 2 -> B-frames<16 |
408f50eb | 495 | .outputOption('-pix_fmt yuv420p') // allows import of source material with incompatible pixel formats (e.g. MJPEG video) |
4a5ccac5 | 496 | .outputOption('-map_metadata -1') // strip all metadata |
4176e227 | 497 | .outputOption('-movflags faststart') |
4176e227 | 498 | |
536598cf | 499 | const parsedAudio = await audio.get(input) |
4176e227 | 500 | |
cdf4cb9e C |
501 | if (!parsedAudio.audioStream) { |
502 | localCommand = localCommand.noAudio() | |
503 | } else if ((await checkFFmpegEncoders()).get('libfdk_aac')) { // we favor VBR, if a good AAC encoder is available | |
504 | localCommand = localCommand | |
4176e227 RK |
505 | .audioCodec('libfdk_aac') |
506 | .audioQuality(5) | |
cdf4cb9e | 507 | } else { |
536598cf | 508 | // we try to reduce the ceiling bitrate by making rough matches of bitrates |
cdf4cb9e | 509 | // of course this is far from perfect, but it might save some space in the end |
536598cf C |
510 | localCommand = localCommand.audioCodec('aac') |
511 | ||
a1587156 | 512 | const audioCodecName = parsedAudio.audioStream['codec_name'] |
cdf4cb9e | 513 | |
a1587156 C |
514 | if (audio.bitrate[audioCodecName]) { |
515 | const bitrate = audio.bitrate[audioCodecName](parsedAudio.audioStream['bit_rate']) | |
64e3e270 | 516 | if (bitrate !== undefined && bitrate !== -1) localCommand = localCommand.audioBitrate(bitrate) |
cdf4cb9e | 517 | } |
4176e227 RK |
518 | } |
519 | ||
536598cf C |
520 | if (fps) { |
521 | // Constrained Encoding (VBV) | |
522 | // https://slhck.info/video/2017/03/01/rate-control.html | |
523 | // https://trac.ffmpeg.org/wiki/Limiting%20the%20output%20bitrate | |
524 | const targetBitrate = getTargetBitrate(resolution, fps, VIDEO_TRANSCODING_FPS) | |
525 | localCommand = localCommand.outputOptions([ `-maxrate ${targetBitrate}`, `-bufsize ${targetBitrate * 2}` ]) | |
526 | ||
527 | // Keyframe interval of 2 seconds for faster seeking and resolution switching. | |
528 | // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html | |
529 | // https://superuser.com/a/908325 | |
530 | localCommand = localCommand.outputOption(`-g ${fps * 2}`) | |
531 | } | |
bcf21a37 | 532 | |
cdf4cb9e | 533 | return localCommand |
4176e227 | 534 | } |
14aed608 | 535 | |
a1587156 | 536 | function presetCopy (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand { |
14aed608 C |
537 | return command |
538 | .format('mp4') | |
539 | .videoCodec('copy') | |
540 | .audioCodec('copy') | |
541 | } | |
5c7d6508 | 542 | |
a1587156 | 543 | function presetOnlyAudio (command: ffmpeg.FfmpegCommand): ffmpeg.FfmpegCommand { |
5c7d6508 | 544 | return command |
545 | .format('mp4') | |
546 | .audioCodec('copy') | |
547 | .noVideo() | |
548 | } |