I tested timg recently on some local .gif files. I should preface this here that some
of these .gif files are decades old. I think I got them from various sources on
the world wide web, but I don't recall where or when exactly.
Let me describe the two ways I see how timg operates here, when it comes to
.gif files (that is, animated .gif files).
Number one: timg simply shows the image in place, never changing anything.
That is, it is animated, just like it were animated in a browser. I believe this is
the correct and default behaviour. Each new frame in that .gif file, appears
exactly over the old frame. Pixel-perfect rendering or display of the image on
the terminal.
But, for Number two, I also notice something odd for some .gif files, but not
all of them. That is, timg shows each frame from top to bottom, but it seems
to attempt to overlay the prior frame. The result is some kind of strange
downward scrolling where parts of the old frame are shifted upwards, and
then the new (next) frame is shown.
The following partial screenshot show this in KDE konsole; I had to blur some
things black :)
https://i.imgur.com/1g7W5Iv.png
I tested this on some .gif files, and from my about 20 local .gif files, about 4
show this behaviour.
I do not know the code, but could it be that internally timg uses a different
strategy to render those frames? Perhaps the offset calculated is incorrect,
or the format of those .gif files causes a delegation to some renderer or
so that is working incorrectly. It is a bit strange because most of those
.gif files work fine, so it may also have something to do with these .gif
files. I am not very familiar with the .gif format, having downloaded those
images literally decades ago. So I am not even sure if it is worth to report
this; these days I transitioned into .avif files for images, and quite frankly
I would not mind abandoning the .gif format entirely - but either way I
wanted to report this behaviour. Please feel free to close this issue here
at any moment in time, I just wanted to report it. (I may try to see if I
can create a new .gif file from those individual frames and see if that
fixes the issue at hand, but as I so rarely use .gif files myself it is also not
a huge priority right now.)
I tested timg recently on some local .gif files. I should preface this here that some
of these .gif files are decades old. I think I got them from various sources on
the world wide web, but I don't recall where or when exactly.
Let me describe the two ways I see how timg operates here, when it comes to
.gif files (that is, animated .gif files).
Number one: timg simply shows the image in place, never changing anything.
That is, it is animated, just like it were animated in a browser. I believe this is
the correct and default behaviour. Each new frame in that .gif file, appears
exactly over the old frame. Pixel-perfect rendering or display of the image on
the terminal.
But, for Number two, I also notice something odd for some .gif files, but not
all of them. That is, timg shows each frame from top to bottom, but it seems
to attempt to overlay the prior frame. The result is some kind of strange
downward scrolling where parts of the old frame are shifted upwards, and
then the new (next) frame is shown.
The following partial screenshot show this in KDE konsole; I had to blur some
things black :)
https://i.imgur.com/1g7W5Iv.png
I tested this on some .gif files, and from my about 20 local .gif files, about 4
show this behaviour.
I do not know the code, but could it be that internally timg uses a different
strategy to render those frames? Perhaps the offset calculated is incorrect,
or the format of those .gif files causes a delegation to some renderer or
so that is working incorrectly. It is a bit strange because most of those
.gif files work fine, so it may also have something to do with these .gif
files. I am not very familiar with the .gif format, having downloaded those
images literally decades ago. So I am not even sure if it is worth to report
this; these days I transitioned into .avif files for images, and quite frankly
I would not mind abandoning the .gif format entirely - but either way I
wanted to report this behaviour. Please feel free to close this issue here
at any moment in time, I just wanted to report it. (I may try to see if I
can create a new .gif file from those individual frames and see if that
fixes the issue at hand, but as I so rarely use .gif files myself it is also not
a huge priority right now.)