Transparent background for GIF

[bipinkrish]

I would be good idea to save gif with transparent background by default then white background so it suits for most of the users.

Just need to set alpha channel value 0 here

• https://github.com/sign-language-processing/pose/blob/master/src/python/pose_format/pose_visualizer.py#L113

• https://github.com/sign-language-processing/pose/blob/master/src/python/pose_format/pose_visualizer.py#L231

[AmitMY]

I agree that it would be best to save gifs with transparency.
I'll be honest - I didn't know that the GIF format even supported transparency, but just learned that it is only partial:

the GIF format doesn't support partial (alpha-channel) transparency

I don't have time to look into this in the next week or so, so I invite you to contribute this modification if you want it soon.

[bipinkrish]

I tried to do it, I got transparent background but hand movements become clustered and it wasn't smooth, I cant figure out why would background color change affects the hand motion.

[AmitMY]

If you create a PR, and specify the issue (with an example GIF), I might be able to look at it faster

[bipinkrish]

sure

[bipinkrish]

I will soon open a PR to show the changes but this is the result

Expected:

Actuall:

[AmitMY]

Ah! so the issue is probably this one https://stackoverflow.com/questions/60948028/python-pillow-transparent-gif-isnt-working

You have not specified the disposal parameter of Image.save(). This parameter controls how the previous frame is disposed in relation to the background. If unspecified, the previous frame "lingers" into the next frame(s). Adding disposal=2 should resolve that particular issue.

[bipinkrish]

Yeah according to this GIF has border problems but APNG doesn't have that

GIF:

PNG :

Should I stick with PNG?

[AmitMY]

Glad to see you got it working.
Personally, for a moving video, I would choose webm. If you can't use a video, webp would be a good alternative.
if you really want to use gif, maybe there's a way to set the border's alpha to 0, which will fix the white patches

[AmitMY]

Thanks for solving your issue!