How to hardcode subtitles into a video in Manjaro Linux

Published on 2019/03/14

Table of contents

.srt subtitles

Ever wondered how to hardcode .srt subtitles into a video?
Or how to modify the font size before fusing them?

This tutorial will show you how to do that.

From ISO-8859-1 to UTF-8

For the process to be successful, we need the .srt file to be UTF-8 encoded.
Spanish subtitles files are commonly encoded as ISO-8859-1.

So, is it ISO-8859-1 or UTF-8?
Find out with:


If it’s UTF-8 encoded, you’ll see something like: UTF-8 Unicode text, with CRLF line terminators

If it’s ISO-8859-1 it’d be: ISO-8859 text, with CRLF line terminators

To convert an .srt file from ISO-8859-1 encoding to UTF-8, use:

iconv -f ISO-8859-1 -t UTF-8 >>

Now your UTF-8 encoded subs will be in the file.

Hardcode the .srt file

Let’s suppose your subtitleless video file is called video.mp4.

To merge the .srt and the .mp4 files together, type:

ffmpeg -i video.mp4 -vf video-with-subs.mp4

.ass subtitles

The downside to using a pure .srt file, is that you cannot format the subtitles.

From .srt to .ass

That’s why it’s better to convert them to .ass:

ffmpeg -i subs.ass

Hardcode the .ass file

To format the subtitles, just open the .ass file in a text editor and modify the font size, etc.

Then hardcode the subtitles with:

ffmpeg -i video.mp4 -vf ass=subs.ass video-with-subs.mp4

That’s it!

P.S. The process is CPU intensive and uses all the cores available, so the more you have the better!


— lt

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