Slow when opening .webp and .gifs animations

[UnderPL]

IrfanView (4.62 x64 - all plugins) takes quite a long time (~1-3/4 seconds) to open animated gifs or webp. I've tried disabling resampling but the result is the same.

The delay increase with the file size. For files around 4-5mb, it's not that bad (like 500ms to 1 sec) but it's slow enough that I can see the irfanview background (black) and my mouse cursor to change to the hourglass cursor. When goign through a lot of files, it's pretty annoying.

For bigger files (15mb to 40), it takes like 3-4 seconds which is pretty slow. I've tested with files from multiples sources and it's the same. Moving the files to a pretty fast (EVO 970) SDD does nothing.

I then tested another image viewer (nomacs) and it's instantaneous, no loading at all even for the 20-40mb webp.

[Bhikkhu Pesala]

I don't have such large animated GIFs to test. The exact load time can be seen in image information. I get times of 15 milliseconds for files of 1.74 Mbytes. Please provide a link to a few large files.

[UnderPL]

The image properties report 15 miliseconds but it took like 2 seconds before I could actually see the image.

https://gofile.io/d/ppImPA

or

https://www49.zippyshare.com/v/fQAk6WLK/file.html

[JendaLinda]

I takes about 2 seconds to open the file. That's reasonable for such high resolution animation.

[Bhikkhu Pesala]

Not slow here in my opinion. I think that Nomac appears to open it quickly is because it renders only the first frame, whilst IrfanView is caching all 151 frames before it displays anything.

[j7n]

The reported loading time seems to be for one frame. The program also consumes a whopping 640 MB of memory with this file, indicating that it has decoded all frames in advance. The WebP format is also a bit slow in general. I think you are pushing the limits of what the format was meant to do. If you need a video of a naked woman, make regular video that will be decoded progressively. I see no Gifs to test in this thread, but I have previously found video-Gifs to "lag" the web browser too.

[UnderPL]

Seem like you guys are more interested in arguing that the delay is acceptable and that's it's not slow.

l'll give it to you that slow is subjective but compared to nomacs, it is very very slow. Try to browse quickly through a folder with multiple of theses animations, for 100 similar file you lose 2+ min. For 1000 and more, 30+ min. Also try opening the file with irfanview and immediately after with nomacs and you'll have an idea on how faster nomacs is.

j7n The choice of format is not mine, I haven't made the video although I did edit the animation to censor the woman in bikini.

[JendaLinda]

There are different approaches how programs can handle animations. The animation can be decoded frame by frame, each frame is decompressed just before displaying it. Or the program can decode all frames in advance, decompressing the whole file into memory. Both approaches have advantages and disadvantages. IrfanView is doing the latter.

To quickly view the contents of a folder, you can use IrfanView thumbnails. It loads only the first frame as a preview.

[Bhikkhu Pesala]

l’ll give it to you that slow is subjective but compared to nomacs, it is very very slow.

I suggest using Nomacs if that is better for your needs, but it might be worth sending an email to Irfan Skiljan (see Help, About IrfanView) asking him to include an option to load only the first frame of animations.