No transparent background in sixel

[niksingh710]

General description of bug:

• What happened: if using sixel to show image then it is rendering a black background instead of transparent one
• What should happen: should render a transparent background
• Where did you get the binary: Arch linux (Aur)

in the image the first one is with --logo that is using symbols.

I can confirm that rendering sixel using chafa renders transparent background in terminal but in fastfetch it renders black bg.

[CarterLi]

sixel doesn't seem to support transparent pixels. There are opening PRs in the fork repo but never got merged.

You should try other image protocols

[niksingh710]

don't know why but for me

if using chafa with sixel the bg is transparent. terminal i am using is foot and tmux as multiplexer and Arch linux is the distro.

[CarterLi]

Try changing the terminal background now?

[niksingh710]

@CarterLi

[CarterLi]

Please paste the result of chafa -f sixels out.png > out.sixel here

I can confirm the behavior with foot, but not konsole and iterm...

[niksingh710]

Please paste the result of chafa -f sixels out.png > out.sixel here

I can confirm the behavior with foot, but not konsole and iterm...

yep maybe the foot implementation of sixel includes patches for the bg transparency.
i am just unsure why fastfetch is rendering background is there any way that can be avoided?

[CarterLi]

Chafa uses its own sixel image convertion implementation, while fastfetch uses imagemagick. Imagemagick doesn't support transparent background for sixel and simply convert transparent pixels to black.

It's possible for fastfetch to use chafa for sixel image generation, but it seems that a lot of terminals don't support transparent backgrounds for sixel image and render a weird bg color. I don't think it's the time of switching.

It's still possible to use transparent background logos:

$ chafa -s WxH out.png > out.sixel
$ fastfetch --raw out.sixel --logo-width W --logo-height H --logo-padding-top 2 # There is a bug that makes fastfetch crash if --logo-padding-top is not set

[niksingh710]

this hack works......

[emilrueh]

no matter what I do. the command $ fastfetch --raw out.sixel --logo-width W --logo-height H --logo-padding-top 2 # There is a bug that makes fastfetch crash if --logo-padding-top is not set does set the logo and it is in-fact transparent but alway in a size that essentially covers the entire terminal.

Neither setting the width and height in the command, nor in the config changes anything about it.

Also changing the image size to something smaller and re-running it through chafa changes anything, except for it now being massive and in rendered in terrible resolution.