GIF animation problem

[mmmmario]

Hi,

I discovered this problem: when a GIF file contains more frames than one and delay between frames is zero, the picture should be displayed imidietly, but IrfanView does not do so.

Another problem: when number of replay of picture is zero IrfanView replays again and again. Here are some examples. (this pictures are using frames with custom palete to show more than 256 colors in final picture)

http://i.iinfo.cz/urs-att/gif2_9-115572840440173.gif

http://i.iinfo.cz/urs-att/gif2_a-115572847111449.gif

http://i.iinfo.cz/urs-att/gif2_b-115572849944000.gif

http://i.iinfo.cz/urs-att/gif2_c-115572856438743.gif

http://i.iinfo.cz/urs-att/gif2_d-115572862703120.gif

http://i.iinfo.cz/urs-att/gif2_e-115572866858321.gif

I know that some pictures are designed to have delay set to zero and viewers use some delay. But in documentation of GIF format is written that viewers should render frames imidietly.

[Bhikkhu Pesala]

I wonder why you don't use PNG instead?

IV displays the image a lot faster than either FastStone Image Viewer or Opera. Internet Explorer 7 displays only one frame.

[Sam_Zen]

This is about animated GIFs, so I don't see the link to PNG, at first hand, to be honest.
I downloaded the files, and they were played fluently, without frame-delay. So it seemed correct.

Of course the animation is looping, but that's normal, because IV doesn't read the 'number of loops' variable of the GIF.
(In this case all GIFs are set to 'play loop 1 time'..)

But there is something peculiar about these files.
In IrfanView they don't show my default background color for the transparent regions. Some green, some yellow.
If I stop the animation with "G", so it returns to the first frame, the transparent region is gone, and IV shows just the visual part. In the case of the first GIF, a very tiny bitmap of 1 pixel high.
Could be caused by having different palettes of each frame.

Different apps to make the animated GIF can play a role as well. Animation Shop doesn't accept a frame-delay of zero.
And it produced after an open and save again a file which showed twice as slow in buildup with IV..

Then a Firefox-test: Same slowness, but the transparency is correct, and it stops after one time.

A proposal : Let's not use the word 'picture' here, because it can be confusing.
A total animation can be called like that, but a single frame also.

[Bhikkhu Pesala]

This is about animated GIFs, so I don't see the link to PNG, at first hand, to be honest.

It is about using animation to simulate more colours. By using a frame gap of zero the idea is to create a static image, not an animation. So why not use PNG?

[Sam_Zen]

I understand.

[midora]

It is about using animation to simulate more colours. By using a frame gap of zero the idea is to create a static image, not an animation. So why not use PNG?

Yeah, this is a relict from the good old times ;-)
Remember there were Graphic Cards only supporting 256 colors.
If you switched the images fast enough in the frame gap of the card you could fake more colors because the human eyes are a little bit slow.

But this never really worked quite good with gif animations.