Set bitrate limits for transcoding (fixes #638) (#1135)

* Set bitrate limits for transcoding (fixes #638)

* added optimization script and test, changed stuff

* fix test, improve docs

* re-add optimize-old-videos script

* added documentation

* Don't optimize videos without valid UUID, or redundancy videos

* move getUUIDFromFilename

* fix tests?

* update torrent and file size, some more fixes/improvements

* use higher bitrate for high fps video, adjust bitrates

* add test video

* don't throw error if resolution is undefined

* generate test fixture on the fly

* use random noise video for bitrate test, add promise

* shorten test video to avoid timeout

* use existing function to optimize video

* various fixes

* increase test timeout

* limit test fixture size, add link

* test fixes

* add await

* more test fixes, add -b:v parameter

* replace ffmpeg wiki link

* fix ffmpeg params

* fix unit test

* add test fixture to .gitgnore

* add video transcoding fps model

* add missing file

3 files changed, 38 insertions, 9 deletions

diff --git a/scripts/help.sh b/scripts/help.sh
index 8ac090139..bc38bdb40 100755
--- a/scripts/help.sh
+++ b/scripts/help.sh
@@ -18,6 +18,7 @@ printf "  reset-password -- -u [user] -> Reset the password of user [user]\n"
 printf "  create-transcoding-job -- -v [video UUID] \n"
 printf "                              -> Create a transcoding job for a particular video\n"
 printf "  prune-storage               -> Delete (after confirmation) unknown video files/thumbnails/previews... (due to a bad video deletion, transcoding job not finished...)\n"
+printf "  optimize-old-videos         -> Re-transcode videos that have a high bitrate, to make them suitable for streaming over slow connections"
 printf "  dev                         -> Watch, run the livereload and run the server so that you can develop the application\n"
 printf "  start                       -> Run the server\n"
 printf "  update-host                 -> Upgrade scheme/host in torrent files according to the webserver configuration (config/ folder)\n"
diff --git a/scripts/optimize-old-videos.ts b/scripts/optimize-old-videos.ts
new file mode 100644
index 000000000..ab44acfbe
--- /dev/null
+++ b/scripts/optimize-old-videos.ts
@@ -0,0 +1,36 @@
+import { join } from 'path'
+import { readdir } from 'fs-extra'
+import { CONFIG, VIDEO_TRANSCODING_FPS } from '../server/initializers/constants'
+import { getVideoFileResolution, getVideoFileBitrate, getVideoFileFPS } from '../server/helpers/ffmpeg-utils'
+import { getMaxBitrate } from '../shared/models/videos'
+import { VideoRedundancyModel } from '../server/models/redundancy/video-redundancy'
+import { VideoModel } from '../server/models/video/video'
+import { getUUIDFromFilename } from '../server/helpers/utils'
+import { optimizeVideofile } from '../server/lib/video-transcoding'
+
+run()
+  .then(() => process.exit(0))
+  .catch(err => {
+    console.error(err)
+    process.exit(-1)
+  })
+
+async function run () {
+  const files = await readdir(CONFIG.STORAGE.VIDEOS_DIR)
+  for (const file of files) {
+    const inputPath = join(CONFIG.STORAGE.VIDEOS_DIR, file)
+    const videoBitrate = await getVideoFileBitrate(inputPath)
+    const fps = await getVideoFileFPS(inputPath)
+    const resolution = await getVideoFileResolution(inputPath)
+    const uuid = getUUIDFromFilename(file)
+
+    const isLocalVideo = await VideoRedundancyModel.isLocalByVideoUUIDExists(uuid)
+    const isMaxBitrateExceeded =
+      videoBitrate > getMaxBitrate(resolution.videoFileResolution, fps, VIDEO_TRANSCODING_FPS)
+    if (uuid && isLocalVideo && isMaxBitrateExceeded) {
+      const videoModel = await VideoModel.loadByUUIDWithFile(uuid)
+      await optimizeVideofile(videoModel, inputPath)
+    }
+  }
+  console.log('Finished optimizing videos')
+}
diff --git a/scripts/prune-storage.ts b/scripts/prune-storage.ts
index 4088fa700..4ab0b4863 100755
--- a/scripts/prune-storage.ts
+++ b/scripts/prune-storage.ts
@@ -5,6 +5,7 @@ import { VideoModel } from '../server/models/video/video'
 import { initDatabaseModels } from '../server/initializers'
 import { remove, readdir } from 'fs-extra'
 import { VideoRedundancyModel } from '../server/models/redundancy/video-redundancy'
+import { getUUIDFromFilename } from '../server/helpers/utils'
 
 run()
   .then(() => process.exit(0))
@@ -82,15 +83,6 @@ async function pruneDirectory (directory: string, onlyOwned = false) {
   return toDelete
 }
 
-function getUUIDFromFilename (filename: string) {
-  const regex = /[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}/
-  const result = filename.match(regex)
-
-  if (!result || Array.isArray(result) === false) return null
-
-  return result[0]
-}
-
 async function askConfirmation () {
   return new Promise((res, rej) => {
     prompt.start()