Is it possible to add a custom thumbnail using ffmpeg to a .webm file?

Tech QnA
1

Is there any way to add a custom thumbnail to a .webm file using FFmpeg?
I tried the following commands using FFmpeg version: 4.2.7-0ubuntu0.1, but not working for me :frowning:

ffmpeg -i ‘input.webm’ -i ‘thumbnail.jpg’ -map 1 -map 0 -c copy -disposition:0 attached_pic ‘output.webm’

2

Yes, it is possible to add a custom thumbnail to a .webm file using FFmpeg.

You can use the “thumbnail” filter in FFmpeg.
Here is an example command that will extract a thumbnail from the video at the 5-second mark and save it to a file named “thumbnail.jpg”:

ffmpeg -i input.webm -vf "thumbnail,scale=640:360" -frames:v 1 thumbnail.jpg

To add the thumbnail to the .webm file as a poster image, you can use the “metadata” option in FFmpeg. Here is an example command that will add the thumbnail to the .webm file as a poster image:

ffmpeg -i input.webm -i thumbnail.jpg -map 0 -map 1 -c copy -c:v:1 image2 -metadata:s:v:1 title="Album cover" -metadata:s:v:1 comment="Cover (front)" output.webm

The above command will take the input video “input.webm” and the thumbnail image “thumbnail.jpg” and create a new .webm file “output.webm” with the thumbnail added as a poster image.

3

Let me try this and then will get back to you if need more help. Thanks

4

Can you specify the position and duration of the thumbnail in the .webm file?

1 Like
5

Sadly, unlike some other formats, the WebM format itself does not inherently allow the idea of thumbnails with precise placements or durations. Typically, the FFmpeg-attached thumbnail will be a static image linked to the full video.

It could be worthwhile to think about other options if you require advanced thumbnail functionality, like making a brief video clip that functions as a thumbnail and then adding it to the WebM file.

1 Like
6

Got it, can the process of adding a custom thumbnail be automated for batch processing with FFmpeg?

1 Like
7

Yes, you can use a script or a loop to automate the bulk processing process. This is very useful if you have several .webm files with associated thumbnail photos. Using FFmpeg, a straightforward script may loop through the files and attach the matching thumbnails, expediting the process for numerous videos.

#!/bin/bash
for file in *.webm; do
  thumbnail="thumbnail_${file%.webm}.jpg"
  ffmpeg -i "$file" -i "$thumbnail" -c copy -map 0 -map 1 -metadata:s:v title="Thumbnail" -metadata:s:v comment="Thumbnail" "output_${file}"
done

Every .webm file in the current directory is processed by this script, which also adds the relevant thumbnail and saves the result with a new filename. Adapt the script to your directory layout and file naming conventions.

1 Like
8

Thank you for your quick response.