1---
2title: "Using ffmpeg to combine videos side by side"
3url: using-ffmpeg-to-combine-video-side-by-side.html
4date: 2023-11-04T09:04:28+02:00
5type: note
6draft: false
7---
8
9I had a 4 webm videos (each 492x451) that I wanted to combine to be played side
10by side and I tried [iMovie](https://support.apple.com/imovie) and
11[Kdenlive](https://kdenlive.org/) and failed to do it in an easy way. I needed
12this for Github readme file so it also needed to be a GIF.
13
14The following is the [ffmpeg](https://ffmpeg.org/) version of it.
15
16```sh
17ffmpeg -y \
18 -i 01.webm \
19 -i 02.webm \
20 -i 03.webm \
21 -i 04.webm \
22 -filter_complex "\
23 [0:v] trim=duration=8, setpts=PTS-STARTPTS, scale=492x451, fps=6 [a0]; \
24 [1:v] trim=duration=8, setpts=PTS-STARTPTS, scale=492x451, fps=6 [a1]; \
25 [2:v] trim=duration=8, setpts=PTS-STARTPTS, scale=492x451, fps=6 [a2]; \
26 [3:v] trim=duration=8, setpts=PTS-STARTPTS, scale=492x451, fps=6 [a3]; \
27 [a0][a1][a2][a3] xstack=inputs=4:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0, scale=1000:-1 [v]" \
28 -map "[v]" \
29 -crf 23 \
30 -preset veryfast \
31 trigraphs.gif
32```
33
34- This will produce `trigraphs.gif` that is also scaled to max 1000px in width
35 (refer to `scale=1000:-1`).
36- The important part for 4x1 stack is `xstack=inputs=4:layout=0_0|w0_0|w0+w1_0|w0+w1+w2_0`.
37- This will also cap frame rate to 6 (refer to `fps=6`) since that is enough and
38 this makes playback of GIFs smoother in a browser.
39
40