Improve target bitrate calculation

24 files changed, 263 insertions, 204 deletions

diff --git a/scripts/create-transcoding-job.ts b/scripts/create-transcoding-job.ts
index 65e65b616..3a552c19a 100755
--- a/scripts/create-transcoding-job.ts
+++ b/scripts/create-transcoding-job.ts
@@ -47,13 +47,13 @@ async function run () {
   if (!video) throw new Error('Video not found.')
 
   const dataInput: VideoTranscodingPayload[] = []
-  const { videoFileResolution } = await video.getMaxQualityResolution()
+  const { resolution } = await video.getMaxQualityResolution()
 
   // Generate HLS files
   if (options.generateHls || CONFIG.TRANSCODING.WEBTORRENT.ENABLED === false) {
     const resolutionsEnabled = options.resolution
       ? [ options.resolution ]
-      : computeResolutionsToTranscode(videoFileResolution, 'vod').concat([ videoFileResolution ])
+      : computeResolutionsToTranscode(resolution, 'vod').concat([ resolution ])
 
     for (const resolution of resolutionsEnabled) {
       dataInput.push({
diff --git a/scripts/optimize-old-videos.ts b/scripts/optimize-old-videos.ts
index bde9d1e01..9e66105dd 100644
--- a/scripts/optimize-old-videos.ts
+++ b/scripts/optimize-old-videos.ts
@@ -1,9 +1,7 @@
 import { registerTSPaths } from '../server/helpers/register-ts-paths'
 registerTSPaths()
 
-import { VIDEO_TRANSCODING_FPS } from '../server/initializers/constants'
 import { getDurationFromVideoFile, getVideoFileBitrate, getVideoFileFPS, getVideoFileResolution } from '../server/helpers/ffprobe-utils'
-import { getMaxBitrate } from '../shared/models/videos'
 import { VideoModel } from '../server/models/video/video'
 import { optimizeOriginalVideofile } from '../server/lib/transcoding/video-transcoding'
 import { initDatabaseModels } from '../server/initializers/database'
@@ -11,6 +9,7 @@ import { basename, dirname } from 'path'
 import { copy, move, remove } from 'fs-extra'
 import { createTorrentAndSetInfoHash } from '@server/helpers/webtorrent'
 import { getVideoFilePath } from '@server/lib/video-paths'
+import { getMaxBitrate } from '@shared/core-utils'
 
 run()
   .then(() => process.exit(0))
@@ -42,13 +41,13 @@ async function run () {
     for (const file of video.VideoFiles) {
       currentFilePath = getVideoFilePath(video, file)
 
-      const [ videoBitrate, fps, resolution ] = await Promise.all([
+      const [ videoBitrate, fps, dataResolution ] = await Promise.all([
         getVideoFileBitrate(currentFilePath),
         getVideoFileFPS(currentFilePath),
         getVideoFileResolution(currentFilePath)
       ])
 
-      const maxBitrate = getMaxBitrate(resolution.videoFileResolution, fps, VIDEO_TRANSCODING_FPS)
+      const maxBitrate = getMaxBitrate({ ...dataResolution, fps })
       const isMaxBitrateExceeded = videoBitrate > maxBitrate
       if (isMaxBitrateExceeded) {
         console.log(
diff --git a/server/controllers/api/videos/upload.ts b/server/controllers/api/videos/upload.ts
index 408f677ff..89f50714d 100644
--- a/server/controllers/api/videos/upload.ts
+++ b/server/controllers/api/videos/upload.ts
@@ -239,7 +239,7 @@ async function buildNewFile (video: MVideo, videoPhysicalFile: express.VideoUplo
     videoFile.resolution = DEFAULT_AUDIO_RESOLUTION
   } else {
     videoFile.fps = await getVideoFileFPS(videoPhysicalFile.path)
-    videoFile.resolution = (await getVideoFileResolution(videoPhysicalFile.path)).videoFileResolution
+    videoFile.resolution = (await getVideoFileResolution(videoPhysicalFile.path)).resolution
   }
 
   videoFile.filename = generateWebTorrentVideoFilename(videoFile.resolution, videoFile.extname)
diff --git a/server/helpers/ffmpeg-utils.ts b/server/helpers/ffmpeg-utils.ts
index 7f84a049f..830625cc6 100644
--- a/server/helpers/ffmpeg-utils.ts
+++ b/server/helpers/ffmpeg-utils.ts
@@ -3,10 +3,18 @@ import * as ffmpeg from 'fluent-ffmpeg'
 import { readFile, remove, writeFile } from 'fs-extra'
 import { dirname, join } from 'path'
 import { FFMPEG_NICE, VIDEO_LIVE } from '@server/initializers/constants'
-import { AvailableEncoders, EncoderOptions, EncoderOptionsBuilder, EncoderProfile, VideoResolution } from '../../shared/models/videos'
+import { pick } from '@shared/core-utils'
+import {
+  AvailableEncoders,
+  EncoderOptions,
+  EncoderOptionsBuilder,
+  EncoderOptionsBuilderParams,
+  EncoderProfile,
+  VideoResolution
+} from '../../shared/models/videos'
 import { CONFIG } from '../initializers/config'
 import { execPromise, promisify0 } from './core-utils'
-import { computeFPS, ffprobePromise, getAudioStream, getVideoFileBitrate, getVideoFileFPS } from './ffprobe-utils'
+import { computeFPS, ffprobePromise, getAudioStream, getVideoFileBitrate, getVideoFileFPS, getVideoFileResolution } from './ffprobe-utils'
 import { processImage } from './image-utils'
 import { logger } from './logger'
 
@@ -217,13 +225,16 @@ async function getLiveTranscodingCommand (options: {
   masterPlaylistName: string
 
   resolutions: number[]
+
+  // Input information
   fps: number
   bitrate: number
+  ratio: number
 
   availableEncoders: AvailableEncoders
   profile: string
 }) {
-  const { rtmpUrl, outPath, resolutions, fps, bitrate, availableEncoders, profile, masterPlaylistName } = options
+  const { rtmpUrl, outPath, resolutions, fps, bitrate, availableEncoders, profile, masterPlaylistName, ratio } = options
   const input = rtmpUrl
 
   const command = getFFmpeg(input, 'live')
@@ -253,9 +264,12 @@ async function getLiveTranscodingCommand (options: {
       availableEncoders,
       profile,
 
-      fps: resolutionFPS,
       inputBitrate: bitrate,
+      inputRatio: ratio,
+
       resolution,
+      fps: resolutionFPS,
+
       streamNum: i,
       videoType: 'live' as 'live'
     }
@@ -502,7 +516,7 @@ function getHLSVideoPath (options: HLSTranscodeOptions | HLSFromTSTranscodeOptio
 // Run encoder builder depending on available encoders
 // Try encoders by priority: if the encoder is available, run the chosen profile or fallback to the default one
 // If the default one does not exist, check the next encoder
-async function getEncoderBuilderResult (options: {
+async function getEncoderBuilderResult (options: EncoderOptionsBuilderParams & {
   streamType: 'video' | 'audio'
   input: string
 
@@ -510,13 +524,8 @@ async function getEncoderBuilderResult (options: {
   profile: string
 
   videoType: 'vod' | 'live'
-
-  resolution: number
-  inputBitrate: number
-  fps?: number
-  streamNum?: number
 }) {
-  const { availableEncoders, input, profile, resolution, streamType, fps, inputBitrate, streamNum, videoType } = options
+  const { availableEncoders, profile, streamType, videoType } = options
 
   const encodersToTry = availableEncoders.encodersToTry[videoType][streamType]
   const encoders = availableEncoders.available[videoType]
@@ -546,7 +555,7 @@ async function getEncoderBuilderResult (options: {
       }
     }
 
-    const result = await builder({ input, resolution, inputBitrate, fps, streamNum })
+    const result = await builder(pick(options, [ 'input', 'resolution', 'inputBitrate', 'fps', 'inputRatio', 'streamNum' ]))
 
     return {
       result,
@@ -581,6 +590,7 @@ async function presetVideo (options: {
   // Audio encoder
   const parsedAudio = await getAudioStream(input, probe)
   const bitrate = await getVideoFileBitrate(input, probe)
+  const { ratio } = await getVideoFileResolution(input, probe)
 
   let streamsToProcess: StreamType[] = [ 'audio', 'video' ]
 
@@ -600,6 +610,7 @@ async function presetVideo (options: {
       profile,
       fps,
       inputBitrate: bitrate,
+      inputRatio: ratio,
       videoType: 'vod' as 'vod'
     })
 
diff --git a/server/helpers/ffprobe-utils.ts b/server/helpers/ffprobe-utils.ts
index bc87e49b1..e58444b07 100644
--- a/server/helpers/ffprobe-utils.ts
+++ b/server/helpers/ffprobe-utils.ts
@@ -1,5 +1,6 @@
 import * as ffmpeg from 'fluent-ffmpeg'
-import { getMaxBitrate, VideoFileMetadata, VideoResolution } from '../../shared/models/videos'
+import { getMaxBitrate } from '@shared/core-utils'
+import { VideoFileMetadata, VideoResolution, VideoTranscodingFPS } from '../../shared/models/videos'
 import { CONFIG } from '../initializers/config'
 import { VIDEO_TRANSCODING_FPS } from '../initializers/constants'
 import { logger } from './logger'
@@ -75,7 +76,7 @@ function getMaxAudioBitrate (type: 'aac' | 'mp3' | string, bitrate: number) {
   }
 }
 
-async function getVideoStreamSize (path: string, existingProbe?: ffmpeg.FfprobeData) {
+async function getVideoStreamSize (path: string, existingProbe?: ffmpeg.FfprobeData): Promise<{ width: number, height: number }> {
   const videoStream = await getVideoStreamFromFile(path, existingProbe)
 
   return videoStream === null
@@ -146,7 +147,10 @@ async function getVideoFileResolution (path: string, existingProbe?: ffmpeg.Ffpr
   const size = await getVideoStreamSize(path, existingProbe)
 
   return {
-    videoFileResolution: Math.min(size.height, size.width),
+    width: size.width,
+    height: size.height,
+    ratio: Math.max(size.height, size.width) / Math.min(size.height, size.width),
+    resolution: Math.min(size.height, size.width),
     isPortraitMode: size.height > size.width
   }
 }
@@ -243,7 +247,7 @@ async function canDoQuickVideoTranscode (path: string, probe?: ffmpeg.FfprobeDat
   const videoStream = await getVideoStreamFromFile(path, probe)
   const fps = await getVideoFileFPS(path, probe)
   const bitRate = await getVideoFileBitrate(path, probe)
-  const resolution = await getVideoFileResolution(path, probe)
+  const resolutionData = await getVideoFileResolution(path, probe)
 
   // If ffprobe did not manage to guess the bitrate
   if (!bitRate) return false
@@ -253,7 +257,7 @@ async function canDoQuickVideoTranscode (path: string, probe?: ffmpeg.FfprobeDat
   if (videoStream['codec_name'] !== 'h264') return false
   if (videoStream['pix_fmt'] !== 'yuv420p') return false
   if (fps < VIDEO_TRANSCODING_FPS.MIN || fps > VIDEO_TRANSCODING_FPS.MAX) return false
-  if (bitRate > getMaxBitrate(resolution.videoFileResolution, fps, VIDEO_TRANSCODING_FPS)) return false
+  if (bitRate > getMaxBitrate({ ...resolutionData, fps })) return false
 
   return true
 }
@@ -278,7 +282,7 @@ async function canDoQuickAudioTranscode (path: string, probe?: ffmpeg.FfprobeDat
   return true
 }
 
-function getClosestFramerateStandard (fps: number, type: 'HD_STANDARD' | 'STANDARD'): number {
+function getClosestFramerateStandard <K extends keyof Pick<VideoTranscodingFPS, 'HD_STANDARD' | 'STANDARD'>> (fps: number, type: K) {
   return VIDEO_TRANSCODING_FPS[type].slice(0)
                                     .sort((a, b) => fps % a - fps % b)[0]
 }
diff --git a/server/initializers/migrations/0075-video-resolutions.ts b/server/initializers/migrations/0075-video-resolutions.ts
index 496125adb..6e8e47acb 100644
--- a/server/initializers/migrations/0075-video-resolutions.ts
+++ b/server/initializers/migrations/0075-video-resolutions.ts
@@ -27,17 +27,15 @@ function up (utils: {
         const ext = matches[2]
 
         const p = getVideoFileResolution(join(videoFileDir, videoFile))
-          .then(height => {
+          .then(async ({ resolution }) => {
             const oldTorrentName = uuid + '.torrent'
-            const newTorrentName = uuid + '-' + height + '.torrent'
-            return rename(join(torrentDir, oldTorrentName), join(torrentDir, newTorrentName)).then(() => height)
-          })
-          .then(height => {
-            const newVideoFileName = uuid + '-' + height + '.' + ext
-            return rename(join(videoFileDir, videoFile), join(videoFileDir, newVideoFileName)).then(() => height)
-          })
-          .then(height => {
-            const query = 'UPDATE "VideoFiles" SET "resolution" = ' + height +
+            const newTorrentName = uuid + '-' + resolution + '.torrent'
+            await rename(join(torrentDir, oldTorrentName), join(torrentDir, newTorrentName)).then(() => resolution)
+
+            const newVideoFileName = uuid + '-' + resolution + '.' + ext
+            await rename(join(videoFileDir, videoFile), join(videoFileDir, newVideoFileName)).then(() => resolution)
+
+            const query = 'UPDATE "VideoFiles" SET "resolution" = ' + resolution +
                           ' WHERE "videoId" = (SELECT "id" FROM "Videos" WHERE "uuid" = \'' + uuid + '\')'
             return utils.sequelize.query(query)
           })
diff --git a/server/lib/job-queue/handlers/video-file-import.ts b/server/lib/job-queue/handlers/video-file-import.ts
index 4d199f247..2f4abf730 100644
--- a/server/lib/job-queue/handlers/video-file-import.ts
+++ b/server/lib/job-queue/handlers/video-file-import.ts
@@ -32,7 +32,7 @@ async function processVideoFileImport (job: Bull.Job) {
   const newResolutionPayload = {
     type: 'new-resolution-to-webtorrent' as 'new-resolution-to-webtorrent',
     videoUUID: video.uuid,
-    resolution: data.videoFileResolution,
+    resolution: data.resolution,
     isPortraitMode: data.isPortraitMode,
     copyCodecs: false,
     isNewVideo: false
@@ -51,13 +51,13 @@ export {
 // ---------------------------------------------------------------------------
 
 async function updateVideoFile (video: MVideoFullLight, inputFilePath: string) {
-  const { videoFileResolution } = await getVideoFileResolution(inputFilePath)
+  const { resolution } = await getVideoFileResolution(inputFilePath)
   const { size } = await stat(inputFilePath)
   const fps = await getVideoFileFPS(inputFilePath)
 
   const fileExt = getLowercaseExtension(inputFilePath)
 
-  const currentVideoFile = video.VideoFiles.find(videoFile => videoFile.resolution === videoFileResolution)
+  const currentVideoFile = video.VideoFiles.find(videoFile => videoFile.resolution === resolution)
 
   if (currentVideoFile) {
     // Remove old file and old torrent
@@ -69,9 +69,9 @@ async function updateVideoFile (video: MVideoFullLight, inputFilePath: string) {
   }
 
   const newVideoFile = new VideoFileModel({
-    resolution: videoFileResolution,
+    resolution,
     extname: fileExt,
-    filename: generateWebTorrentVideoFilename(videoFileResolution, fileExt),
+    filename: generateWebTorrentVideoFilename(resolution, fileExt),
     size,
     fps,
     videoId: video.id
diff --git a/server/lib/job-queue/handlers/video-import.ts b/server/lib/job-queue/handlers/video-import.ts
index 5fd2039b1..fec553f2b 100644
--- a/server/lib/job-queue/handlers/video-import.ts
+++ b/server/lib/job-queue/handlers/video-import.ts
@@ -114,7 +114,7 @@ async function processFile (downloader: () => Promise<string>, videoImport: MVid
       throw new Error('The user video quota is exceeded with this video to import.')
     }
 
-    const { videoFileResolution } = await getVideoFileResolution(tempVideoPath)
+    const { resolution } = await getVideoFileResolution(tempVideoPath)
     const fps = await getVideoFileFPS(tempVideoPath)
     const duration = await getDurationFromVideoFile(tempVideoPath)
 
@@ -122,9 +122,9 @@ async function processFile (downloader: () => Promise<string>, videoImport: MVid
     const fileExt = getLowercaseExtension(tempVideoPath)
     const videoFileData = {
       extname: fileExt,
-      resolution: videoFileResolution,
+      resolution,
       size: stats.size,
-      filename: generateWebTorrentVideoFilename(videoFileResolution, fileExt),
+      filename: generateWebTorrentVideoFilename(resolution, fileExt),
       fps,
       videoId: videoImport.videoId
     }
diff --git a/server/lib/job-queue/handlers/video-live-ending.ts b/server/lib/job-queue/handlers/video-live-ending.ts
index 386ccdc7b..aa5bd573a 100644
--- a/server/lib/job-queue/handlers/video-live-ending.ts
+++ b/server/lib/job-queue/handlers/video-live-ending.ts
@@ -96,12 +96,12 @@ async function saveLive (video: MVideo, live: MVideoLive, streamingPlaylist: MSt
     const probe = await ffprobePromise(concatenatedTsFilePath)
     const { audioStream } = await getAudioStream(concatenatedTsFilePath, probe)
 
-    const { videoFileResolution, isPortraitMode } = await getVideoFileResolution(concatenatedTsFilePath, probe)
+    const { resolution, isPortraitMode } = await getVideoFileResolution(concatenatedTsFilePath, probe)
 
     const outputPath = await generateHlsPlaylistResolutionFromTS({
       video: videoWithFiles,
       concatenatedTsFilePath,
-      resolution: videoFileResolution,
+      resolution,
       isPortraitMode,
       isAAC: audioStream?.codec_name === 'aac'
     })
diff --git a/server/lib/job-queue/handlers/video-transcoding.ts b/server/lib/job-queue/handlers/video-transcoding.ts
index 2abb351ce..876d1460c 100644
--- a/server/lib/job-queue/handlers/video-transcoding.ts
+++ b/server/lib/job-queue/handlers/video-transcoding.ts
@@ -136,7 +136,7 @@ async function onVideoFileOptimizer (
   if (videoArg === undefined) return undefined
 
   // Outside the transaction (IO on disk)
-  const { videoFileResolution, isPortraitMode } = await videoArg.getMaxQualityResolution()
+  const { resolution, isPortraitMode } = await videoArg.getMaxQualityResolution()
 
   // Maybe the video changed in database, refresh it
   const videoDatabase = await VideoModel.loadAndPopulateAccountAndServerAndTags(videoArg.uuid)
@@ -155,7 +155,7 @@ async function onVideoFileOptimizer (
   })
   const hasHls = await createHlsJobIfEnabled(user, originalFileHLSPayload)
 
-  const hasNewResolutions = await createLowerResolutionsJobs(videoDatabase, user, videoFileResolution, isPortraitMode, 'webtorrent')
+  const hasNewResolutions = await createLowerResolutionsJobs(videoDatabase, user, resolution, isPortraitMode, 'webtorrent')
 
   if (!hasHls && !hasNewResolutions) {
     // No transcoding to do, it's now published
diff --git a/server/lib/live/live-manager.ts b/server/lib/live/live-manager.ts
index b19ecef6f..2a429fb33 100644
--- a/server/lib/live/live-manager.ts
+++ b/server/lib/live/live-manager.ts
@@ -202,7 +202,7 @@ class LiveManager {
     const now = Date.now()
     const probe = await ffprobePromise(rtmpUrl)
 
-    const [ { videoFileResolution }, fps, bitrate ] = await Promise.all([
+    const [ { resolution, ratio }, fps, bitrate ] = await Promise.all([
       getVideoFileResolution(rtmpUrl, probe),
       getVideoFileFPS(rtmpUrl, probe),
       getVideoFileBitrate(rtmpUrl, probe)
@@ -210,13 +210,13 @@ class LiveManager {
 
     logger.info(
       '%s probing took %d ms (bitrate: %d, fps: %d, resolution: %d)',
-      rtmpUrl, Date.now() - now, bitrate, fps, videoFileResolution, lTags(sessionId, video.uuid)
+      rtmpUrl, Date.now() - now, bitrate, fps, resolution, lTags(sessionId, video.uuid)
     )
 
-    const allResolutions = this.buildAllResolutionsToTranscode(videoFileResolution)
+    const allResolutions = this.buildAllResolutionsToTranscode(resolution)
 
     logger.info(
-      'Will mux/transcode live video of original resolution %d.', videoFileResolution,
+      'Will mux/transcode live video of original resolution %d.', resolution,
       { allResolutions, ...lTags(sessionId, video.uuid) }
     )
 
@@ -229,6 +229,7 @@ class LiveManager {
       rtmpUrl,
       fps,
       bitrate,
+      ratio,
       allResolutions
     })
   }
@@ -240,9 +241,10 @@ class LiveManager {
     rtmpUrl: string
     fps: number
     bitrate: number
+    ratio: number
     allResolutions: number[]
   }) {
-    const { sessionId, videoLive, streamingPlaylist, allResolutions, fps, bitrate, rtmpUrl } = options
+    const { sessionId, videoLive, streamingPlaylist, allResolutions, fps, bitrate, ratio, rtmpUrl } = options
     const videoUUID = videoLive.Video.uuid
     const localLTags = lTags(sessionId, videoUUID)
 
@@ -257,6 +259,7 @@ class LiveManager {
       streamingPlaylist,
       rtmpUrl,
       bitrate,
+      ratio,
       fps,
       allResolutions
     })
diff --git a/server/lib/live/shared/muxing-session.ts b/server/lib/live/shared/muxing-session.ts
index 62708b14b..a80abc843 100644
--- a/server/lib/live/shared/muxing-session.ts
+++ b/server/lib/live/shared/muxing-session.ts
@@ -54,9 +54,11 @@ class MuxingSession extends EventEmitter {
   private readonly streamingPlaylist: MStreamingPlaylistVideo
   private readonly rtmpUrl: string
   private readonly fps: number
-  private readonly bitrate: number
   private readonly allResolutions: number[]
 
+  private readonly bitrate: number
+  private readonly ratio: number
+
   private readonly videoId: number
   private readonly videoUUID: string
   private readonly saveReplay: boolean
@@ -85,6 +87,7 @@ class MuxingSession extends EventEmitter {
     rtmpUrl: string
     fps: number
     bitrate: number
+    ratio: number
     allResolutions: number[]
   }) {
     super()
@@ -96,7 +99,10 @@ class MuxingSession extends EventEmitter {
     this.streamingPlaylist = options.streamingPlaylist
     this.rtmpUrl = options.rtmpUrl
     this.fps = options.fps
+
     this.bitrate = options.bitrate
+    this.ratio = options.bitrate
+
     this.allResolutions = options.allResolutions
 
     this.videoId = this.videoLive.Video.id
@@ -122,6 +128,7 @@ class MuxingSession extends EventEmitter {
         resolutions: this.allResolutions,
         fps: this.fps,
         bitrate: this.bitrate,
+        ratio: this.ratio,
 
         availableEncoders: VideoTranscodingProfilesManager.Instance.getAvailableEncoders(),
         profile: CONFIG.LIVE.TRANSCODING.PROFILE
diff --git a/server/lib/transcoding/video-transcoding-profiles.ts b/server/lib/transcoding/video-transcoding-profiles.ts
index 2309f38d4..bca6dfccd 100644
--- a/server/lib/transcoding/video-transcoding-profiles.ts
+++ b/server/lib/transcoding/video-transcoding-profiles.ts
@@ -1,23 +1,24 @@
 import { logger } from '@server/helpers/logger'
-import { AvailableEncoders, EncoderOptionsBuilder, getTargetBitrate, VideoResolution } from '../../../shared/models/videos'
+import { getAverageBitrate } from '@shared/core-utils'
+import { AvailableEncoders, EncoderOptionsBuilder, EncoderOptionsBuilderParams } from '../../../shared/models/videos'
 import { buildStreamSuffix, resetSupportedEncoders } from '../../helpers/ffmpeg-utils'
 import { canDoQuickAudioTranscode, ffprobePromise, getAudioStream, getMaxAudioBitrate } from '../../helpers/ffprobe-utils'
-import { VIDEO_TRANSCODING_FPS } from '../../initializers/constants'
 
 /**
  *
  * Available encoders and profiles for the transcoding jobs
  * These functions are used by ffmpeg-utils that will get the encoders and options depending on the chosen profile
  *
+ * Resources:
+ *  * https://slhck.info/video/2017/03/01/rate-control.html
+ *  * https://trac.ffmpeg.org/wiki/Limiting%20the%20output%20bitrate
  */
 
-// Resources:
-//  * https://slhck.info/video/2017/03/01/rate-control.html
-//  * https://trac.ffmpeg.org/wiki/Limiting%20the%20output%20bitrate
+const defaultX264VODOptionsBuilder: EncoderOptionsBuilder = async (options: EncoderOptionsBuilderParams) => {
+  const { fps, inputRatio, inputBitrate } = options
+  if (!fps) return { outputOptions: [ ] }
 
-const defaultX264VODOptionsBuilder: EncoderOptionsBuilder = async ({ inputBitrate, resolution, fps }) => {
-  const targetBitrate = buildTargetBitrate({ inputBitrate, resolution, fps })
-  if (!targetBitrate) return { outputOptions: [ ] }
+  const targetBitrate = capBitrate(inputBitrate, getAverageBitrate({ ...options, fps, ratio: inputRatio }))
 
   return {
     outputOptions: [
@@ -29,8 +30,10 @@ const defaultX264VODOptionsBuilder: EncoderOptionsBuilder = async ({ inputBitrat
   }
 }
 
-const defaultX264LiveOptionsBuilder: EncoderOptionsBuilder = async ({ resolution, fps, inputBitrate, streamNum }) => {
-  const targetBitrate = buildTargetBitrate({ inputBitrate, resolution, fps })
+const defaultX264LiveOptionsBuilder: EncoderOptionsBuilder = async (options: EncoderOptionsBuilderParams) => {
+  const { streamNum, fps, inputBitrate, inputRatio } = options
+
+  const targetBitrate = capBitrate(inputBitrate, getAverageBitrate({ ...options, fps, ratio: inputRatio }))
 
   return {
     outputOptions: [
@@ -231,14 +234,7 @@ export {
 
 // ---------------------------------------------------------------------------
 
-function buildTargetBitrate (options: {
-  inputBitrate: number
-  resolution: VideoResolution
-  fps: number
-}) {
-  const { inputBitrate, resolution, fps } = options
-
-  const targetBitrate = getTargetBitrate(resolution, fps, VIDEO_TRANSCODING_FPS)
+function capBitrate (inputBitrate: number, targetBitrate: number) {
   if (!inputBitrate) return targetBitrate
 
   return Math.min(targetBitrate, inputBitrate)
diff --git a/server/tests/api/live/live.ts b/server/tests/api/live/live.ts
index 4095cdb1c..ba952aff5 100644
--- a/server/tests/api/live/live.ts
+++ b/server/tests/api/live/live.ts
@@ -3,7 +3,7 @@
 import 'mocha'
 import * as chai from 'chai'
 import { basename, join } from 'path'
-import { ffprobePromise, getVideoFileBitrate, getVideoStreamFromFile } from '@server/helpers/ffprobe-utils'
+import { ffprobePromise, getVideoStreamFromFile } from '@server/helpers/ffprobe-utils'
 import {
   checkLiveCleanupAfterSave,
   checkLiveSegmentHash,
diff --git a/server/tests/api/videos/video-transcoder.ts b/server/tests/api/videos/video-transcoder.ts
index 2a09e95bf..f67752d69 100644
--- a/server/tests/api/videos/video-transcoder.ts
+++ b/server/tests/api/videos/video-transcoder.ts
@@ -3,6 +3,7 @@
 import 'mocha'
 import * as chai from 'chai'
 import { omit } from 'lodash'
+import { getMaxBitrate } from '@shared/core-utils'
 import {
   buildAbsoluteFixturePath,
   cleanupTests,
@@ -17,8 +18,7 @@ import {
   waitJobs,
   webtorrentAdd
 } from '@shared/extra-utils'
-import { getMaxBitrate, HttpStatusCode, VideoResolution, VideoState } from '@shared/models'
-import { VIDEO_TRANSCODING_FPS } from '../../../../server/initializers/constants'
+import { HttpStatusCode, VideoState } from '@shared/models'
 import {
   canDoQuickTranscode,
   getAudioStream,
@@ -191,15 +191,6 @@ describe('Test video transcoding', function () {
     it('Should accept and transcode additional extensions', async function () {
       this.timeout(300_000)
 
-      let tempFixturePath: string
-
-      {
-        tempFixturePath = await generateHighBitrateVideo()
-
-        const bitrate = await getVideoFileBitrate(tempFixturePath)
-        expect(bitrate).to.be.above(getMaxBitrate(VideoResolution.H_1080P, 25, VIDEO_TRANSCODING_FPS))
-      }
-
       for (const fixture of [ 'video_short.mkv', 'video_short.avi' ]) {
         const attributes = {
           name: fixture,
@@ -555,14 +546,7 @@ describe('Test video transcoding', function () {
     it('Should respect maximum bitrate values', async function () {
       this.timeout(160_000)
 
-      let tempFixturePath: string
-
-      {
-        tempFixturePath = await generateHighBitrateVideo()
-
-        const bitrate = await getVideoFileBitrate(tempFixturePath)
-        expect(bitrate).to.be.above(getMaxBitrate(VideoResolution.H_1080P, 25, VIDEO_TRANSCODING_FPS))
-      }
+      const tempFixturePath = await generateHighBitrateVideo()
 
       const attributes = {
         name: 'high bitrate video',
@@ -586,10 +570,12 @@ describe('Test video transcoding', function () {
 
           const bitrate = await getVideoFileBitrate(path)
           const fps = await getVideoFileFPS(path)
-          const { videoFileResolution } = await getVideoFileResolution(path)
+          const dataResolution = await getVideoFileResolution(path)
+
+          expect(resolution).to.equal(resolution)
 
-          expect(videoFileResolution).to.equal(resolution)
-          expect(bitrate).to.be.below(getMaxBitrate(videoFileResolution, fps, VIDEO_TRANSCODING_FPS))
+          const maxBitrate = getMaxBitrate({ ...dataResolution, fps })
+          expect(bitrate).to.be.below(maxBitrate)
         }
       }
     })
diff --git a/server/tests/cli/optimize-old-videos.ts b/server/tests/cli/optimize-old-videos.ts
index 579b2e7d8..9b75ae164 100644
--- a/server/tests/cli/optimize-old-videos.ts
+++ b/server/tests/cli/optimize-old-videos.ts
@@ -2,6 +2,7 @@
 
 import 'mocha'
 import * as chai from 'chai'
+import { getMaxBitrate } from '@shared/core-utils'
 import {
   cleanupTests,
   createMultipleServers,
@@ -12,9 +13,7 @@ import {
   wait,
   waitJobs
 } from '@shared/extra-utils'
-import { getMaxBitrate, VideoResolution } from '@shared/models'
 import { getVideoFileBitrate, getVideoFileFPS, getVideoFileResolution } from '../../helpers/ffprobe-utils'
-import { VIDEO_TRANSCODING_FPS } from '../../initializers/constants'
 
 const expect = chai.expect
 
@@ -30,14 +29,7 @@ describe('Test optimize old videos', function () {
 
     await doubleFollow(servers[0], servers[1])
 
-    let tempFixturePath: string
-
-    {
-      tempFixturePath = await generateHighBitrateVideo()
-
-      const bitrate = await getVideoFileBitrate(tempFixturePath)
-      expect(bitrate).to.be.above(getMaxBitrate(VideoResolution.H_1080P, 25, VIDEO_TRANSCODING_FPS))
-    }
+    const tempFixturePath = await generateHighBitrateVideo()
 
     // Upload two videos for our needs
     await servers[0].videos.upload({ attributes: { name: 'video1', fixture: tempFixturePath } })
@@ -88,10 +80,12 @@ describe('Test optimize old videos', function () {
         const path = servers[0].servers.buildWebTorrentFilePath(file.fileUrl)
         const bitrate = await getVideoFileBitrate(path)
         const fps = await getVideoFileFPS(path)
-        const resolution = await getVideoFileResolution(path)
+        const data = await getVideoFileResolution(path)
+
+        expect(data.resolution).to.equal(file.resolution.id)
 
-        expect(resolution.videoFileResolution).to.equal(file.resolution.id)
-        expect(bitrate).to.be.below(getMaxBitrate(resolution.videoFileResolution, fps, VIDEO_TRANSCODING_FPS))
+        const maxBitrate = getMaxBitrate({ ...data, fps })
+        expect(bitrate).to.be.below(maxBitrate)
       }
     }
   })
diff --git a/server/tests/cli/print-transcode-command.ts b/server/tests/cli/print-transcode-command.ts
index 3a7969e68..e328a6072 100644
--- a/server/tests/cli/print-transcode-command.ts
+++ b/server/tests/cli/print-transcode-command.ts
@@ -3,16 +3,16 @@
 import 'mocha'
 import * as chai from 'chai'
 import { getVideoFileBitrate, getVideoFileFPS } from '@server/helpers/ffprobe-utils'
-import { CLICommand } from '@shared/extra-utils'
-import { getTargetBitrate, VideoResolution } from '../../../shared/models/videos'
-import { VIDEO_TRANSCODING_FPS } from '../../initializers/constants'
+import { getMaxBitrate } from '@shared/core-utils'
+import { buildAbsoluteFixturePath, CLICommand } from '@shared/extra-utils'
+import { VideoResolution } from '../../../shared/models/videos'
 
 const expect = chai.expect
 
 describe('Test create transcoding jobs', function () {
 
   it('Should print the correct command for each resolution', async function () {
-    const fixturePath = 'server/tests/fixtures/video_short.webm'
+    const fixturePath = buildAbsoluteFixturePath('video_short.webm')
     const fps = await getVideoFileFPS(fixturePath)
     const bitrate = await getVideoFileBitrate(fixturePath)
 
@@ -21,7 +21,7 @@ describe('Test create transcoding jobs', function () {
       VideoResolution.H_1080P
     ]) {
       const command = await CLICommand.exec(`npm run print-transcode-command -- ${fixturePath} -r ${resolution}`)
-      const targetBitrate = Math.min(getTargetBitrate(resolution, fps, VIDEO_TRANSCODING_FPS), bitrate)
+      const targetBitrate = Math.min(getMaxBitrate({ resolution, fps, ratio: 16 / 9 }), bitrate)
 
       expect(command).to.includes(`-vf scale=w=-2:h=${resolution}`)
       expect(command).to.includes(`-y -acodec aac -vcodec libx264`)
diff --git a/server/tests/helpers/core-utils.ts b/server/tests/helpers/core-utils.ts
index d5cac51a3..a6bf5b4c5 100644
--- a/server/tests/helpers/core-utils.ts
+++ b/server/tests/helpers/core-utils.ts
@@ -4,6 +4,8 @@ import 'mocha'
 import * as chai from 'chai'
 import { snakeCase } from 'lodash'
 import validator from 'validator'
+import { getAverageBitrate, getMaxBitrate } from '@shared/core-utils'
+import { VideoResolution } from '@shared/models'
 import { objectConverter, parseBytes } from '../../helpers/core-utils'
 
 const expect = chai.expect
@@ -46,6 +48,9 @@ describe('Parse Bytes', function () {
   it('Should be invalid when given invalid value', async function () {
     expect(parseBytes('6GB 1GB')).to.be.eq(6)
   })
+})
+
+describe('Object', function () {
 
   it('Should convert an object', async function () {
     function keyConverter (k: string) {
@@ -94,3 +99,36 @@ describe('Parse Bytes', function () {
     expect(obj['my_super_key']).to.be.undefined
   })
 })
+
+describe('Bitrate', function () {
+
+  it('Should get appropriate max bitrate', function () {
+    const tests = [
+      { resolution: VideoResolution.H_240P, ratio: 16 / 9, fps: 24, min: 600, max: 800 },
+      { resolution: VideoResolution.H_360P, ratio: 16 / 9, fps: 24, min: 1200, max: 1600 },
+      { resolution: VideoResolution.H_480P, ratio: 16 / 9, fps: 24, min: 2000, max: 2300 },
+      { resolution: VideoResolution.H_720P, ratio: 16 / 9, fps: 24, min: 4000, max: 4400 },
+      { resolution: VideoResolution.H_1080P, ratio: 16 / 9, fps: 24, min: 8000, max: 10000 },
+      { resolution: VideoResolution.H_4K, ratio: 16 / 9, fps: 24, min: 25000, max: 30000 }
+    ]
+
+    for (const test of tests) {
+      expect(getMaxBitrate(test)).to.be.above(test.min * 1000).and.below(test.max * 1000)
+    }
+  })
+
+  it('Should get appropriate average bitrate', function () {
+    const tests = [
+      { resolution: VideoResolution.H_240P, ratio: 16 / 9, fps: 24, min: 350, max: 450 },
+      { resolution: VideoResolution.H_360P, ratio: 16 / 9, fps: 24, min: 700, max: 900 },
+      { resolution: VideoResolution.H_480P, ratio: 16 / 9, fps: 24, min: 1100, max: 1300 },
+      { resolution: VideoResolution.H_720P, ratio: 16 / 9, fps: 24, min: 2300, max: 2500 },
+      { resolution: VideoResolution.H_1080P, ratio: 16 / 9, fps: 24, min: 4700, max: 5000 },
+      { resolution: VideoResolution.H_4K, ratio: 16 / 9, fps: 24, min: 15000, max: 17000 }
+    ]
+
+    for (const test of tests) {
+      expect(getAverageBitrate(test)).to.be.above(test.min * 1000).and.below(test.max * 1000)
+    }
+  })
+})
diff --git a/shared/core-utils/index.ts b/shared/core-utils/index.ts
index 2a7d4d982..e0a6a8087 100644
--- a/shared/core-utils/index.ts
+++ b/shared/core-utils/index.ts
@@ -5,3 +5,4 @@ export * from './plugins'
 export * from './renderer'
 export * from './users'
 export * from './utils'
+export * from './videos'
diff --git a/shared/core-utils/videos/bitrate.ts b/shared/core-utils/videos/bitrate.ts
new file mode 100644
index 000000000..3d4e47906
--- /dev/null
+++ b/shared/core-utils/videos/bitrate.ts
@@ -0,0 +1,86 @@
+import { VideoResolution } from "@shared/models"
+
+type BitPerPixel = { [ id in VideoResolution ]: number }
+
+// https://bitmovin.com/video-bitrate-streaming-hls-dash/
+
+const averageBitPerPixel: BitPerPixel = {
+  [VideoResolution.H_NOVIDEO]: 0,
+  [VideoResolution.H_240P]: 0.17,
+  [VideoResolution.H_360P]: 0.15,
+  [VideoResolution.H_480P]: 0.12,
+  [VideoResolution.H_720P]: 0.11,
+  [VideoResolution.H_1080P]: 0.10,
+  [VideoResolution.H_1440P]: 0.09,
+  [VideoResolution.H_4K]: 0.08
+}
+
+const maxBitPerPixel: BitPerPixel = {
+  [VideoResolution.H_NOVIDEO]: 0,
+  [VideoResolution.H_240P]: 0.29,
+  [VideoResolution.H_360P]: 0.26,
+  [VideoResolution.H_480P]: 0.22,
+  [VideoResolution.H_720P]: 0.19,
+  [VideoResolution.H_1080P]: 0.17,
+  [VideoResolution.H_1440P]: 0.16,
+  [VideoResolution.H_4K]: 0.14
+}
+
+function getAverageBitrate (options: {
+  resolution: VideoResolution
+  ratio: number
+  fps: number
+}) {
+  const targetBitrate = calculateBitrate({ ...options, bitPerPixel: averageBitPerPixel })
+  if (!targetBitrate) return 192 * 1000
+
+  return targetBitrate
+}
+
+function getMaxBitrate (options: {
+  resolution: VideoResolution
+  ratio: number
+  fps: number
+}) {
+  const targetBitrate = calculateBitrate({ ...options, bitPerPixel: maxBitPerPixel })
+  if (!targetBitrate) return 256 * 1000
+
+  return targetBitrate
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  getAverageBitrate,
+  getMaxBitrate
+}
+
+// ---------------------------------------------------------------------------
+
+function calculateBitrate (options: {
+  bitPerPixel: BitPerPixel
+  resolution: VideoResolution
+  ratio: number
+  fps: number
+}) {
+  const { bitPerPixel, resolution, ratio, fps } = options
+
+  const resolutionsOrder = [
+    VideoResolution.H_4K,
+    VideoResolution.H_1440P,
+    VideoResolution.H_1080P,
+    VideoResolution.H_720P,
+    VideoResolution.H_480P,
+    VideoResolution.H_360P,
+    VideoResolution.H_240P,
+    VideoResolution.H_NOVIDEO
+  ]
+
+  for (const toTestResolution of resolutionsOrder) {
+    if (toTestResolution <= resolution) {
+      return resolution * resolution * ratio * fps * bitPerPixel[toTestResolution]
+    }
+  }
+
+  throw new Error('Unknown resolution ' + resolution)
+}
diff --git a/shared/core-utils/videos/index.ts b/shared/core-utils/videos/index.ts
new file mode 100644
index 000000000..5a1145f1a
--- /dev/null
+++ b/shared/core-utils/videos/index.ts
@@ -0,0 +1 @@
+export * from './bitrate'
diff --git a/shared/extra-utils/miscs/generate.ts b/shared/extra-utils/miscs/generate.ts
index 8d6435481..a03a20049 100644
--- a/shared/extra-utils/miscs/generate.ts
+++ b/shared/extra-utils/miscs/generate.ts
@@ -1,8 +1,20 @@
+import { expect } from 'chai'
 import * as ffmpeg from 'fluent-ffmpeg'
 import { ensureDir, pathExists } from 'fs-extra'
 import { dirname } from 'path'
+import { getVideoFileBitrate, getVideoFileFPS, getVideoFileResolution } from '@server/helpers/ffprobe-utils'
+import { getMaxBitrate } from '@shared/core-utils'
 import { buildAbsoluteFixturePath } from './tests'
 
+async function ensureHasTooBigBitrate (fixturePath: string) {
+  const bitrate = await getVideoFileBitrate(fixturePath)
+  const dataResolution = await getVideoFileResolution(fixturePath)
+  const fps = await getVideoFileFPS(fixturePath)
+
+  const maxBitrate = getMaxBitrate({ ...dataResolution, fps })
+  expect(bitrate).to.be.above(maxBitrate)
+}
+
 async function generateHighBitrateVideo () {
   const tempFixturePath = buildAbsoluteFixturePath('video_high_bitrate_1080p.mp4', true)
 
@@ -28,6 +40,8 @@ async function generateHighBitrateVideo () {
     })
   }
 
+  await ensureHasTooBigBitrate(tempFixturePath)
+
   return tempFixturePath
 }
 
diff --git a/shared/models/videos/video-resolution.enum.ts b/shared/models/videos/video-resolution.enum.ts
index a5d2ac7fa..24cd2d04d 100644
--- a/shared/models/videos/video-resolution.enum.ts
+++ b/shared/models/videos/video-resolution.enum.ts
@@ -1,5 +1,3 @@
-import { VideoTranscodingFPS } from './video-transcoding-fps.model'
-
 export const enum VideoResolution {
   H_NOVIDEO = 0,
   H_240P = 240,
@@ -10,90 +8,3 @@ export const enum VideoResolution {
   H_1440P = 1440,
   H_4K = 2160
 }
-
-/**
- * Bitrate targets for different resolutions, at VideoTranscodingFPS.AVERAGE.
- *
- * Sources for individual quality levels:
- * Google Live Encoder: https://support.google.com/youtube/answer/2853702?hl=en
- * YouTube Video Info: youtube-dl --list-formats, with sample videos
- */
-function getBaseBitrate (resolution: number) {
-  if (resolution === VideoResolution.H_NOVIDEO) {
-    // audio-only
-    return 64 * 1000
-  }
-
-  if (resolution <= VideoResolution.H_240P) {
-    // quality according to Google Live Encoder: 300 - 700 Kbps
-    // Quality according to YouTube Video Info: 285 Kbps
-    return 320 * 1000
-  }
-
-  if (resolution <= VideoResolution.H_360P) {
-    // quality according to Google Live Encoder: 400 - 1,000 Kbps
-    // Quality according to YouTube Video Info: 700 Kbps
-    return 780 * 1000
-  }
-
-  if (resolution <= VideoResolution.H_480P) {
-    // quality according to Google Live Encoder: 500 - 2,000 Kbps
-    // Quality according to YouTube Video Info: 1300 Kbps
-    return 1500 * 1000
-  }
-
-  if (resolution <= VideoResolution.H_720P) {
-    // quality according to Google Live Encoder: 1,500 - 4,000 Kbps
-    // Quality according to YouTube Video Info: 2680 Kbps
-    return 2800 * 1000
-  }
-
-  if (resolution <= VideoResolution.H_1080P) {
-    // quality according to Google Live Encoder: 3000 - 6000 Kbps
-    // Quality according to YouTube Video Info: 5081 Kbps
-    return 5200 * 1000
-  }
-
-  if (resolution <= VideoResolution.H_1440P) {
-    // quality according to Google Live Encoder: 6000 - 13000 Kbps
-    // Quality according to YouTube Video Info: 8600 (av01) - 17000 (vp9.2) Kbps
-    return 10_000 * 1000
-  }
-
-  // 4K
-  // quality according to Google Live Encoder: 13000 - 34000 Kbps
-  return 22_000 * 1000
-}
-
-/**
- * Calculate the target bitrate based on video resolution and FPS.
- *
- * The calculation is based on two values:
- * Bitrate at VideoTranscodingFPS.AVERAGE is always the same as
- * getBaseBitrate(). Bitrate at VideoTranscodingFPS.MAX is always
- * getBaseBitrate() * 1.4. All other values are calculated linearly
- * between these two points.
- */
-export function getTargetBitrate (resolution: number, fps: number, fpsTranscodingConstants: VideoTranscodingFPS) {
-  const baseBitrate = getBaseBitrate(resolution)
-  // The maximum bitrate, used when fps === VideoTranscodingFPS.MAX
-  // Based on numbers from Youtube, 60 fps bitrate divided by 30 fps bitrate:
-  //  720p: 2600 / 1750 = 1.49
-  // 1080p: 4400 / 3300 = 1.33
-  const maxBitrate = baseBitrate * 1.4
-  const maxBitrateDifference = maxBitrate - baseBitrate
-  const maxFpsDifference = fpsTranscodingConstants.MAX - fpsTranscodingConstants.AVERAGE
-  // For 1080p video with default settings, this results in the following formula:
-  // 3300 + (x - 30) * (1320/30)
-  // Example outputs:
-  // 1080p10: 2420 kbps, 1080p30: 3300 kbps, 1080p60: 4620 kbps
-  //  720p10: 1283 kbps,  720p30: 1750 kbps,  720p60: 2450 kbps
-  return Math.floor(baseBitrate + (fps - fpsTranscodingConstants.AVERAGE) * (maxBitrateDifference / maxFpsDifference))
-}
-
-/**
- * The maximum bitrate we expect to see on a transcoded video in bytes per second.
- */
-export function getMaxBitrate (resolution: VideoResolution, fps: number, fpsTranscodingConstants: VideoTranscodingFPS) {
-  return getTargetBitrate(resolution, fps, fpsTranscodingConstants) * 2
-}
diff --git a/shared/models/videos/video-transcoding.model.ts b/shared/models/videos/video-transcoding.model.ts
index f1fe4609b..83b8e98a0 100644
--- a/shared/models/videos/video-transcoding.model.ts
+++ b/shared/models/videos/video-transcoding.model.ts
@@ -2,13 +2,23 @@ import { VideoResolution } from './video-resolution.enum'
 
 // Types used by plugins and ffmpeg-utils
 
-export type EncoderOptionsBuilder = (params: {
+export type EncoderOptionsBuilderParams = {
   input: string
+
   resolution: VideoResolution
-  inputBitrate: number
+
+  // Could be null for "merge audio" transcoding
   fps?: number
+
+  // Could be undefined if we could not get input bitrate (some RTMP streams for example)
+  inputBitrate: number
+  inputRatio: number
+
+  // For lives
   streamNum?: number
-}) => Promise<EncoderOptions> | EncoderOptions
+}
+
+export type EncoderOptionsBuilder = (params: EncoderOptionsBuilderParams) => Promise<EncoderOptions> | EncoderOptions
 
 export interface EncoderOptions {
   copy?: boolean // Copy stream? Default to false