See [official wiki](https://trac.ffmpeg.org/wiki/HowToBurnSubtitlesIntoVideo) and [subtitles docs](https://ffmpeg.org/ffmpeg-filters.html#subtitles-1).

# subtitles video filter

If the subtitle is a separate file called `subtitle.srt`, you can use this command:

```
ffmpeg -i video.avi -vf subtitles=subtitle.srt out.avi
```
If the subtitle is embedded in the container `video.mkv`, you can do this:

```
ffmpeg -i video.mkv -vf subtitles=video.mkv out.avi
```

Note that the subtitles video filter opens the file separately, so if you are also Seeking in the same step, then the subtitles will start at the beginning of the subtitle file. This may or may not be what you want. If you want the burned-in subtitles to start at the same timestamp as the video, you will need to copy the timestamps to the output with `-copyts`, and then additionally seek in output again with the same values that were used for the input. For example, if you wish to start both the output video and subtitles to start 5 minutes into the input file, then you can use a command line this:

```
ffmpeg -ss 5:00.00 -copyts -i video.avi -ss 5:00.00 -vf subtitles=subtitles.srt out.avi
```

## subtitles options
For example, to render the file `sub.srt` on top of the input video, use the command:

```
subtitles=sub.srt
```
which is equivalent to:

```
subtitles=filename=sub.srt
```
To render the default subtitles stream from file `video.mkv`, use:

```
subtitles=video.mkv
```
To render the second subtitles stream from that file, use:

```
subtitles=video.mkv:si=1
```
To make the subtitles stream from `sub.srt` appear in 80% transparent blue DejaVu Serif, use:

```
subtitles=sub.srt:force_style='Fontname=DejaVu Serif,PrimaryColour=&HCCFF0000'
```