Bad GIF implementation

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vykupitel
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Bad GIF implementation

Post by vykupitel » Wed Aug 23, 2006 9:24 am

Hello,

I found that XnView have bad GIF format implementation. Try to look at this GIF in for example Firefox and then in XnView, It is GIF with true colors in many frames with 256 colors.

It is from article from czech opensource site Root.cz, where was published article about GIF.
Last edited by vykupitel on Wed Aug 23, 2006 11:16 am, edited 1 time in total.

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Drahken
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Post by Drahken » Wed Aug 23, 2006 11:10 am

Few (if any) image viewers/editors have a proper gif implementation. View that image in any other viewer/editor and you won't get any better results. The best results come from irfanview, but it keeps animating the pic, jumping back to the begining every time it completes it. Some show only the very first frame, some show nothing but a black screen.
Oh the feuhrer, oh the feuhrer, oh the feuhrer's nipples bonk!

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xnview
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Re: Bad GIF implementation

Post by xnview » Fri Sep 01, 2006 8:42 am

vykupitel wrote:Hello,

I found that XnView have bad GIF format implementation. Try to look at this GIF in for example Firefox and then in XnView, It is GIF with true colors in many frames with 256 colors.

It is from article from czech opensource site Root.cz, where was published article about GIF.
Ok, i'll check...
Pierre.

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XnTriq
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Re: Bad GIF implementation

Post by XnTriq » Sun Sep 03, 2006 8:35 pm

vykupitel wrote:I found that XnView have bad GIF format implementation. Try to look at this GIF in for example Firefox and then in XnView, It is GIF with true colors in many frames with 256 colors.

It is from article from czech opensource site Root.cz, where was published article about GIF.
Coincidently I also took a closer look at this issue a few weeks ago. Here's the original source for that GIF file: Apropos:

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JohnFredC
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Post by JohnFredC » Mon Sep 04, 2006 4:55 pm

Opera(!) and theGimp open that GIF file successfully. Nothing else I have does.
John

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Clo
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No animation

Post by Clo » Mon Sep 04, 2006 7:39 pm

—> JohnFredC

• I've not installed Opera, but I've The Gimp; that pic is displayed OK about the colours,
but here the animation doesn't work :|

- Gimp says : "Video image" :?:

¤ Else, I guess that the very original GIF features might be retrieved¦applied,
and that we might get rid of the "fake" 8-BPP limitation…

:mrgreen: KR
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Last edited by Clo on Tue Sep 05, 2006 2:44 pm, edited 1 time in total.
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JohnFredC
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Post by JohnFredC » Tue Sep 05, 2006 1:03 pm

Well, I was thinking that the animation was an artifact of the method chosen for displaying more than 256 colors. This is a "special case" GIF, after all.

Opera shows the animation. The Gimp seems to hide it, waiting until the paging is complete to display the final image.

I wonder what the creators of that GIF had in mind for the correct rendering...

The correctness of the final image is self-evident once it successfully appears, but is the animation supposed to show, too?
John

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XnTriq
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Post by XnTriq » Tue Sep 05, 2006 10:50 pm

Hi John & Clo :)
JohnFredC wrote:Opera(!) and theGimp open that GIF file successfully. Nothing else I have does.
Both Jasc Animation Shop 3.11 and Gamani GIF Movie Gear 4.01 have no trouble displaying the file, ...
JohnFredC wrote:I wonder what the creators of that GIF had in mind for the correct rendering...

The correctness of the final image is self-evident once it successfully appears, but is the animation supposed to show, too?
... and both programs open it as an animated GIF.
gamani (GIF Movie Gear – Support » [url=http://www.gamani.com/gmgsup.htm#browser]Browser Issues[/url]) wrote:No software is perfect, and Web browsers are no exception to this rule. Over the past few years as the Web has developed, popular Web browsers have been inadvertently released with some, um, limitations, in the way they handle GIF animations. The result is that a Web designer, working with pages that will be viewed using a variety of browsers, needs to be aware of things that might not work properly on some viewing setups.

[...]

Both NS and IE browsers are not entirely accurate with their timing, especially with very short delays between frames. GIF Movie Gear's playback will often be faster than that of a browser if the delays are shorter than 15/100th of a second. Time for download slows playback even more.

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Clo
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Cheese OR dessert !

Post by Clo » Tue Sep 05, 2006 11:08 pm

—> XnTriq

:) Hello !
Both Jasc Animation Shop 3.11 and Gamani GIF Movie Gear 4.01 have no trouble displaying the file
• I've not the Jasc soft, but I've MovieGear and it displays the animation, but does NOT show the right colour-depth !
It shows it only as 8-BPP!

- Hence, I get only cheese OR dessert, not both… :D

:mrgreen: kR
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