Answers.Body: <p>Use</p>
  
  <pre><code>ffmpeg -i input.webm -vf ass=subtitles.ass -b:v 0 -crf 20 output.webm
  </code></pre>
  
  <p>The libvpx encoders for WebM, by default, perform Constrained Quality encoding, and use the bitrate as a ceiling. Default bitrate is 200 kbps. To remove bitrate ceiling, set bitrate to 0. <code>-crf</code> controls the <a href="https://developers.google.com/media/vp9/bitrate-modes/" rel="nofollow noreferrer">quality level</a>.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-05-16T20:32:32.897Z
Answers.Text: Cheers!  Worked perfectly.
Answers.UserDisplayName: Jon
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-05-16T21:06:57.023Z
Answers.Text: @Jon, so why you don't accept this answer? Click on check mark near it.
Answers.UserDisplayName: MarianD
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2019-05-15T05:53:40.113Z
Answers.LastActivityDate: 2019-05-15T06:02:23.490Z
Answers.LastEditDate: 2019-05-15T06:02:23.490Z
Answers.UserDisplayName: Gyan
Body: <p>I'm trying to burn .ass subtitles onto a .webm, using  <code>ffmpeg -i input.webm -vf ass=subtitles.ass output.webm</code>  but it shrinks from like 150MB to 9MB.   How do I add the subtitles without losing quality ?</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-05-14T08:51:35.633Z
Comments.Text: Do you want to mux the subtitles or burn them?
Comments.UserDisplayName: Gyan
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2019-05-14T20:52:50.503Z
Comments.Text: Burn -- based on https://trac.ffmpeg.org/wiki/HowToBurnSubtitlesIntoVideo
Comments.UserDisplayName: Jon
Tags: <ffmpeg><subtitles>
Title: Burn .ass subtitle onto .webm with no loss of quality
UserDisplayName: Jon
ThreadText: # Burn .ass subtitle onto .webm with no loss of quality
  
  (Asked by: username_0 on 2019-05-14)
  
  I'm trying to burn .ass subtitles onto a .webm, using `ffmpeg -i input.webm -vf ass=subtitles.ass output.webm` but it shrinks from like 150MB to 9MB. How do I add the subtitles without losing quality ?
  
  **Tags:** ffmpeg, subtitles
  
  > **Comments:**
  > **username_1**: Do you want to mux the subtitles or burn them?  
  > **username_0**: Burn -- based on https://trac.ffmpeg.org/wiki/HowToBurnSubtitlesIntoVideo  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2019-05-15. Score: 3 | Accepted answer
  
  Use
  
  ```
  ffmpeg -i input.webm -vf ass=subtitles.ass -b:v 0 -crf 20 output.webm
  
  ```
  
  The libvpx encoders for WebM, by default, perform Constrained Quality encoding, and use the bitrate as a ceiling. Default bitrate is 200 kbps. To remove bitrate ceiling, set bitrate to 0. `-crf` controls the [quality level](https://developers.google.com/media/vp9/bitrate-modes/).
  
  > **Comments:**
  > **username_0**: Cheers!  Worked perfectly.  
  > **username_2**: @username_0, so why you don't accept this answer? Click on check mark near it.  
  
  ---
  
  