From 2498aaead1fb4f34c8c375ef9edff33456c4527a Mon Sep 17 00:00:00 2001
From: Chocobozzz <me@florianbigard.com>
Date: Fri, 29 Jan 2021 10:23:33 +0100
Subject: [PATCH] Add plugin transcoding profile guide

---
 server/lib/plugins/register-helpers.ts        |  4 +
 .../plugin-transcoding-manager.model.ts       |  2 +
 support/doc/plugins/guide.md                  | 88 +++++++++++++++++++
 3 files changed, 94 insertions(+)

diff --git a/server/lib/plugins/register-helpers.ts b/server/lib/plugins/register-helpers.ts
index 3a38a4835..1f2a88c27 100644
--- a/server/lib/plugins/register-helpers.ts
+++ b/server/lib/plugins/register-helpers.ts
@@ -438,6 +438,10 @@ export class RegisterHelpers {
 
       addVODEncoderPriority (streamType: 'audio' | 'video', encoder: string, priority: number) {
         return addEncoderPriority('vod', streamType, encoder, priority)
+      },
+
+      removeAllProfilesAndEncoderPriorities () {
+        return self.reinitTranscodingProfilesAndEncoders(self.npmName)
       }
     }
   }
diff --git a/shared/models/plugins/plugin-transcoding-manager.model.ts b/shared/models/plugins/plugin-transcoding-manager.model.ts
index ff89687e9..7dfb51ddf 100644
--- a/shared/models/plugins/plugin-transcoding-manager.model.ts
+++ b/shared/models/plugins/plugin-transcoding-manager.model.ts
@@ -8,4 +8,6 @@ export interface PluginTranscodingManager {
   addLiveEncoderPriority (streamType: 'audio' | 'video', encoder: string, priority: number): void
 
   addVODEncoderPriority (streamType: 'audio' | 'video', encoder: string, priority: number): void
+
+  removeAllProfilesAndEncoderPriorities()
 }
diff --git a/support/doc/plugins/guide.md b/support/doc/plugins/guide.md
index 0d35820e5..9739d117a 100644
--- a/support/doc/plugins/guide.md
+++ b/support/doc/plugins/guide.md
@@ -22,6 +22,7 @@
     - [Translate](#translate)
     - [Get public settings](#get-public-settings)
     - [Add custom fields to video form](#add-custom-fields-to-video-form)
+    - [Add new transcoding profiles](#add-new-transcoding-profiles)
   - [Publishing](#publishing)
 - [Write a plugin/theme](#write-a-plugintheme)
   - [Clone the quickstart repository](#clone-the-quickstart-repository)
@@ -440,7 +441,94 @@ async function register ({
     }
   })
 }
+```
 
+#### Add new transcoding profiles
+
+Adding transcoding profiles allow admins to change ffmpeg encoding parameters and/or encoders.
+A transcoding profile has to be chosen by the admin of the instance using the admin configuration.
+
+```js
+async function register ({
+  transcodingManager
+}) {
+
+  // Adapt bitrate when using libx264 encoder
+  {
+    const builder = (options) => {
+      const { input, resolution, fps, streamNum } = options
+
+      const streamString = streamNum ? ':' + streamNum : ''
+
+      // You can also return a promise
+      return {
+        outputOptions: [
+        // Use a custom bitrate
+          '-b' + streamString + ' 10K'
+        ]
+      }
+    }
+
+    const encoder = 'libx264'
+    const profileName = 'low-quality'
+
+    // Support this profile for VOD transcoding
+    transcodingManager.addVODProfile(encoder, profileName, builder)
+
+    // And/Or support this profile for live transcoding
+    transcodingManager.addLiveProfile(encoder, profileName, builder)
+  }
+
+  {
+    const builder = (options) => {
+      const { streamNum } = options
+
+      const streamString = streamNum ? ':' + streamNum : ''
+
+      // Always copy stream when PeerTube use libfdk_aac or aac encoders
+      return {
+        copy: true
+      }
+    }
+
+    const profileName = 'copy-audio'
+
+    for (const encoder of [ 'libfdk_aac', 'aac' ]) {
+      transcodingManager.addVODProfile(encoder, profileName, builder)
+    }
+  }
+```
+
+PeerTube will try different encoders depending on their priority.
+If the encoder is not available in the current transcoding profile or in ffmpeg, it tries the next one.
+Plugins can change the order of these encoders and add their custom encoders:
+
+```js
+async function register ({
+  transcodingManager
+}) {
+
+  // Adapt bitrate when using libx264 encoder
+  {
+    const builder = () => {
+      return {
+        outputOptions: []
+      }
+    }
+
+    // Support libopus and libvpx-vp9 encoders, just for the example (PeerTube player is only compatible with h264/aac)
+    transcodingManager.addVODProfile('libopus', 'test-vod-profile', builder)
+
+    // Default priorities are ~100
+    // Lowest priority = 1
+    transcodingManager.addVODEncoderPriority('audio', 'libopus', 1000)
+
+    transcodingManager.addVODProfile('libvpx-vp9', 'test-vod-profile', builder)
+    transcodingManager.addVODEncoderPriority('video', 'libvpx-vp9', 1000)
+
+    transcodingManager.addLiveProfile('libopus', 'test-live-profile', builder)
+    transcodingManager.addLiveEncoderPriority('audio', 'libopus', 1000)
+  }
 ```