<p>The subtitles in the MP4 is a mov_text (tx3g) stream which isn't supported in MPEG-TS.</p>

<p>MPEG-TS support either DVD subtitles or DVB teletext. The former is a bitmap subtitle format and ffmpeg can't convert text to bitmap. FFmpeg has no encoder for the latter. Your best bet is to burn the subtitles but this means re-encoding the video.</p>

<pre><code>ffmpeg -i in.mp4 -vf subtitles=in.mp4 -c:v libx264 -c:a copy out.ts
</code></pre>

CC BY-SA 4.0
2019-06-19T16:42:38.640Z
what is the caption format for a regular .ts file viewable on VLC? For example: https://www.dropbox.com/s/u1unlmyketqnv1e/test.ts?dl=0
The format is different from the one created from your command.
angel_30
CC BY-SA 4.0
2019-06-19T18:07:51.767Z
My command makes the captions part of the image. In your sample, the captions are embedded as an element within the video bitstream. ffmpeg can't convert subtitles from a separate stream into those.
Gyan
CC BY-SA 4.0
2019-06-19T18:39:40.870Z
I see. Got it. Tnx.
angel_30
CC BY-SA 4.0
2019-06-18T19:47:59.497Z
2019-06-18T19:47:59.497Z
Gyan
<p>This is a follow-up question from my previous question <a href="https://video.stackexchange.com/questions/27854/errors-in-converting-mp4-to-ts-with-ffmpeg/27855#27855">HERE</a>. I'm trying to convert a caption-embedded .<code>mp4</code> video into a .<code>ts</code> file, simply changing the container format. But once I convert the video, the caption looks different. Not sure what's going on.</p>

<p><a href="http://dropbox.com/s/697c7tuqgkc0bv0/test.mp4?dl=0" rel="nofollow noreferrer">Here</a> is the sample .<code>mp4</code> video. At second 00:34" for example, you see the caption says <code>GARBLED CAPTION INSERTED</code>. But that's not there in the converted <code>.ts</code> file. </p>

<p>What's happening? Any clues?! </p>

<video><ffmpeg><mp4><file-formats><closed-captioning>
Closed Captions missing when converting from mp4 to ts
angel_30
# Closed Captions missing when converting from mp4 to ts

(Asked by: username_0 on 2019-06-18)

This is a follow-up question from my previous question [HERE](https://video.stackexchange.com/questions/27854/errors-in-converting-mp4-to-ts-with-ffmpeg/27855#27855). I'm trying to convert a caption-embedded .`mp4` video into a .`ts` file, simply changing the container format. But once I convert the video, the caption looks different. Not sure what's going on.

[Here](http://dropbox.com/s/697c7tuqgkc0bv0/test.mp4?dl=0) is the sample .`mp4` video. At second 00:34" for example, you see the caption says `GARBLED CAPTION INSERTED`. But that's not there in the converted `.ts` file.

What's happening? Any clues?!

**Tags:** video, ffmpeg, mp4, file-formats, closed-captioning


---

## 1 answers

### Answer by username_1 on 2019-06-18. Score: 2 | Accepted answer

The subtitles in the MP4 is a mov_text (tx3g) stream which isn't supported in MPEG-TS.
MPEG-TS support either DVD subtitles or DVB teletext. The former is a bitmap subtitle format and ffmpeg can't convert text to bitmap. FFmpeg has no encoder for the latter. Your best bet is to burn the subtitles but this means re-encoding the video.
ffmpeg -i in.mp4 -vf subtitles=in.mp4 -c:v libx264 -c:a copy out.ts

> **Comments:**
> **username_0**: what is the caption format for a regular .ts file viewable on VLC? For example: https://www.dropbox.com/s/u1unlmyketqnv1e/test.ts?dl=0 The format is different from the one created from your command.  
> **username_1**: My command makes the captions part of the image. In your sample, the captions are embedded as an element within the video bitstream. ffmpeg can't convert subtitles from a separate stream into those.  
> **username_0**: I see. Got it. Tnx.  

---

