I created a globe with PovRay. Now I created an ini file, which simulates a
rotation of the globe. The result are 180 png Files, with a size of
approximately 200kb.
Now I converted them with IrfanView to 22kb Gif images and created an
animation with Gimp. The final gif file has a size of about 8mb. But it
shouldn't be higher than 200kb.
I don't care if I lose quality of the animation, but I don't know how to
downsize it. Maybe you can give me some hints for this issue.

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PNG has better compression than GIF.

Does Gimp not open PNG files? If I were you I'd go straight from the PNG
files to the gif animation, without separately converting to gif first.

If you want better compression with gif, you may have to play with settings
like color resolution.

 - Slime
 [ http://www.slimeland.com/ ]

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Slime <fak### [at] emailaddress> wrote:
> PNG has better compression than GIF.

  Only if you use the same color depth. His pngs are probably true-color,
while the gifs are only 8-bit and thus smaller. POV-Ray cannot create
8-bit pngs directly (because that would go against its principle of not
saving lossy) but they would need to be converted.

  One way to make better-compressible gifs is to avoid using dithering
when converting the true-color pngs to 8-bit (gif or png). Because only
256 colors are available this may or may not produce visible artifacts.
If not using dithering in the conversion produces acceptable results
then they will usually compress much better than when using dithering.

-- 
                                                          - Warp

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"Sanix" <nomail@nomail> wrote:
> I created a globe with PovRay. Now I created an ini file, which simulates a
> rotation of the globe. The result are 180 png Files, with a size of
> approximately 200kb.
> Now I converted them with IrfanView to 22kb Gif images and created an
> animation with Gimp. The final gif file has a size of about 8mb. But it
> shouldn't be higher than 200kb.
> I don't care if I lose quality of the animation, but I don't know how to
> downsize it. Maybe you can give me some hints for this issue.

I think the problem is that you make an animated gif with 180 frames.
Animated gifs should not have much frames (180 are veeeeeery much frames
for a gif). I'd use about 4 or 8, but not 180, because you are not creating
an animation but a gif for the web probably.

Am I wrong ?

                    Manuel Mata.
                    http://www.mmata.org

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Mata's Manuel is right. Don't put each of your rendered PNGs into the 
animated GIF. Use maybe each 10th of them, and if the result is an animated 
GIF with a globe rotating too fast (because of the fewer frames) than just 
apply a longer display time to each of the frames within the animated GIF.

Experiment with fewer and fewer frames and longer frame display times, until 
you reach the limit of what you would accept. And then you still can do 
more: the mode of how each frame replaces the previous one ("Undraw method") 
can be altered (I use the Microsoft GIF Animator, a free and small and 
simple but usable program). There are modes like undefined, restore 
background, restore previous.

Also use as much transparency as you can, as transparency does not contain 
any color.

I hope the animated GIF has not too big dimensions but rather a small size 
(e.g.: 120x90 pixels or whatever).

There is somewhere another really very great program (a free one!) on the 
Web which is capable to reduce the size of animated GIFs dramatically! But I 
had that program a looong time ago in use; today I don't use it anymore 
since a long time, and don't have it anymore. I don't know its name anymore 
nor its developing company (a known one). I searched on the Web but don't 
find it. However, if you search the Web for "GIF Optimizer", you still find 
a good number of programs which will reduce your animated GIFs size further 
after you finished with Microsoft GIF Animator.

Sven




"Sanix" <nomail@nomail> schrieb im Newsbeitrag 
news:web.445f0d8164e7ca92c2ceb9180@news.povray.org...
>I created a globe with PovRay. Now I created an ini file, which simulates a
> rotation of the globe. The result are 180 png Files, with a size of
> approximately 200kb.
> Now I converted them with IrfanView to 22kb Gif images and created an
> animation with Gimp. The final gif file has a size of about 8mb. But it
> shouldn't be higher than 200kb.
> I don't care if I lose quality of the animation, but I don't know how to
> downsize it. Maybe you can give me some hints for this issue.
>
>
>

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Thank you very much for your answers!
I use now 72 frames. It's much smaller and looks quite ok. Then I optimized
it with a freeware tool. I saw that gimp does it pretty well, so the tool
couldn't create a smaller gif, but I set the colors down to 32 and it's
smaller again.

Now I have another problem:
When people look at the image on IE6, it uses a lot of CPU and begins to
stagnate and it's shown wrongly. If you take Mozilla Firefox, it has nearly
no CPU usage. Do you know why? Is there a setting problem or something like
this?

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Hello there Sanix.
When I make animations, I get those frames like png's files, then i use
gifsicle to stick those together. Gifsicle use gif's for sure.
look at this animations:

http://www.fcfm.uanl.mx/ifi/Galeria.htm

All of them run smooth.

*******************************

"Sanix" <nomail@nomail> wrote:
> Thank you very much for your answers!
> I use now 72 frames. It's much smaller and looks quite ok. Then I optimized
> it with a freeware tool. I saw that gimp does it pretty well, so the tool
> couldn't create a smaller gif, but I set the colors down to 32 and it's
> smaller again.
>
> Now I have another problem:
> When people look at the image on IE6, it uses a lot of CPU and begins to
> stagnate and it's shown wrongly. If you take Mozilla Firefox, it has nearly
> no CPU usage. Do you know why? Is there a setting problem or something like
> this?

Post a reply to this message

Sanix wrote:
> Thank you very much for your answers!
> I use now 72 frames. It's much smaller and looks quite ok.

I also recommend averageing several frames together, rather than just taking 
every 3rd frame or whatever.

So average frames 1,2,3 and use that as frame 1 in your gif.  Then average 
frames 4,5,6 and use that as frame 2.  etc.  That gives a much smoother 
looking result.

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