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VonDuck
05-30-2007, 10:36 AM
Hi

I have been making a gif animation in Adobe ImageReady.. The problem is, that the quality makes the gif dotted. I can't adjust anything that corrects it. I used a jpg picture for background on the animation, and made it black and white with a blue tone to it. Could it be to much for the gif to handle?? Is has 19 pictures in all.. But should that be any reason for the Gif to become dotted in quality??

tech_support
05-30-2007, 10:37 AM
Use Flash.
GIF loses quality especially when it's big.

djr33
05-30-2007, 10:38 AM
GIFs can be set on a scale of quality, for lower filesize, if desired.
First step is to be sure it's at maximum quality (if you can afford the filesize).

However, GIFs limit it to 256 colors, total, so you may just need to use a different format (too bad, since JPEGs aren't animated and animated PNGs aren't supported yet) or make your image simpler, or just live with the dotted look.

Using a custom color pallette might help too, but this is done by default in most cases.

Twey
05-30-2007, 12:43 PM
Use Flash.Using Flash won't help at all, unless you redraw the entire image using vectors. If you simply import the image, or any part of the image, it'll just be an embedded GIF. There's also all the accessibility problems using Flash bring up.
GIF loses quality especially when it's big.No it doesn't. GIF's only limit on quality is its 256 colour limit. Size doesn't matter.
GIFs can be set on a scale of quality, for lower filesize, if desired.No they don't. GIF is a lossless compression format. You're thinking of JPEG.
However, GIFs limit it to 256 colors, total, so you may just need to use a different format (too bad, since JPEGs don't animated and animated PNGs aren't supported yet) or make your image simpler, or just live with the dotted look.They are supported in Firefox. If you really can't bear the loss of quality that GIF is causing, I would recommend perhaps using Javascript to animate a series of JPEGs. You could have the original "dotty" GIF as a fallback for non-Javascript browsers.

djr33
05-30-2007, 12:58 PM
For flash, that would work, assuming you bring in the original. But it would require flash support which is something you should avoid if possible.


No it doesn't. GIF's only limit on quality is its 256 colour limit. Size doesn't matter.Optimization engines have several options, such as how many colors (a 2 color gif is significantly less than 256 to store), the way that nonmatching colors are handled (best-guess or dithering), as well as other little things, like optimizing repeated frames, etc.
The word 'big', though somewhat ambiguous, is true in two ways-- 1. a 'big' animation (many frames) would tend to have many colors, and with each frame, it's more likely that there would be more than 256 colors total. With a 'big' image, the same is true, in that there are more pixels to take up colors, so that would run out of the 256 quickly, too.


No they don't. GIF is a lossless compression format. You're thinking of JPEG.The methods that jpg and gif use to compress differ greatly. JPG tries to hide it from the eye, whereas gif makes it pretty obvious. A gif CAN be more compressed/optimized in that it has fewer colors or less detail (dithering is a main factor there).
While a GIF 'loses' nothing if you save it over and over again*, it still is much lower quality than an original if that original had more than 256 colors or the palette amount of the particular image.
Take a photo. Save as gif. Save as low quality jpg. Which 'lost' more?
(*This is generally the case, but I have on several occasions had weird issues with saving it again, after adding a new color and throwing off the palette, then making many of the other colors change to fit into the new set, so dithering was used and it was all blocky.)

I would recommend perhaps using Javascript to animate a series of JPEGs.Yeah, but only for a slow animation. Anything more than 3 frames per second or slow would likely stutter on a slower system.


They are supported in Firefox.And so is xhtml....

Twey
05-30-2007, 01:13 PM
A gif CAN be more compressed/optimized in that it has fewer colors or less detail (dithering is a main factor there).True. That's not compression, though, per se.
Yeah, but only for a slow animation. Anything more than 3 frames per second or slow would likely stutter on a slower system.Hm, I don't know... I've managed to have Javascript run much more complex operations nicely at 33 frames per second, and my system's moderate but not exceedingly powerful. I should think almost all systems should be able to handle 10FPS quite comfortably.
And so is xhtml....Aye, I wasn't saying they should be used, it was just that the way you said it made it sound as if nothing supported them.

jscheuer1
05-30-2007, 03:52 PM
Quality, compression, and lossless are each both technical and generic terms. Twey is correct when he uses them in their technical sense in this context. However, .gif can be compressed, has quality issues and is not lossless if one is using these terms as generic descriptive words. From that standpoint, its quality is a function of the items djr33 mentioned, perhaps others. It can be generically 'compressed' (made to be a smaller byte size) and, is in fact a compressed format. Anyone who views a complex photograph rendered as a .gif would not think nothing was lost, therefore it is not generically 'lossless', though that technically describes the format accurately.

djr33
05-30-2007, 06:04 PM
lossless only applies to the gif format in terms of generation loss.
Save a jpg at the same quality twice, and it will have more compression artifacts.
Save a gif twice (without changng the colors used) and it will be identical.... losing nothing.

Lossless does not mean that it won't lose anything from the original format.

jscheuer1
05-30-2007, 06:15 PM
lossless only applies to the gif format in terms of generation loss.
Save a jpg at the same quality twice, and it will have more compression artifacts.
Save a gif twice (without changng the colors used) and it will be identical.... losing nothing.

Lossless does not mean that it won't lose anything from the original format.

It also means that it has no artifacts. With .gif compression, all pixels are rendered faithfully within the limits of the given palette. Whereas, with .jpg type compression, artifacts emerge (when done 'right' these are unnoticeable to the casual eye), as that format only strives to make an adequate approximation of the image. That is why .jpg is just about the best compression method (as far as byte size) for web presentation of intricate images.

djr33
05-30-2007, 06:20 PM
Well, I'm not sure if lossless specifically means it has no artifacts, but that has no LOSS. This loss is generation loss.
This works because it has no artifacts, and resaving a jpg causes artifacts to be rendered differently, creating the loss.
The artifacts are related, but not specifically part of it being lossless, except that not having artifacts allows it to be so.
But it's part of the reason it's lossless, not something done as a result of being lossless.

Medyman
06-01-2007, 03:56 AM
For flash, that would work, assuming you bring in the original. But it would require flash support which is something you should avoid if possible.

Not necessarily, you could use the Flash program to create the animation and export as a GIF sequence.

djr33
06-01-2007, 05:04 AM
GIF is the problem, so doing a number of steps and ending up with the same GIF wouldn't help much, would it?
You'd still be stuck with the 256 color limit, among other things.

Twey
06-15-2007, 09:17 AM
That's completely irrelevant... I considered a "moderate spam" infraction, but I think you just didn't realise.

bsmith-tigerteam
07-04-2007, 03:24 AM
I have been making a gif animation in Adobe ImageReady.. The problem is, that the quality makes the gif dotted. I can't adjust anything that corrects it. ...

can we see the image(s)?

djr33
07-04-2007, 03:41 AM
Set the pallete to include your specific color, or use colors that match that colors in the pallete.

Using GIF means you're limited to 256 colors, though you can choose which colors. It will try to guess which color or "dither" which is that dotting process, trying to match a middle color by using half pixels of one close color and half pixels of another closer color.
Image Ready should have an option to turn on dithering or just use a solid, best guess, color.

zuresh
03-19-2008, 07:01 AM
Photoshop Elements is better for making animated gifs. It supports all color..more than 256

Twey
03-19-2008, 07:06 AM
Err, no, the 256-colour limitation is inherent in the GIF format, not any particular image editor. Moreover, computers aren't able to display 'all colour' (not that we could distinguish between the shades if it they could) because that would require a practically infinite amount of storage space to hold these high-precision colour values.

zuresh
03-19-2008, 07:30 AM
:confused:Photoshops save for web gives almost exact colors, but cant make animation. But imageready's save for web option didnt give the exact colors we need for animations. So I use an old version of Photoshop Elements for making animated Gifs. It gives almost every colors in the pdf layers. I mean gives the feel:)

djr33
03-19-2008, 09:02 AM
Simply wrong, as Twey said. You're mistaken. I don't mean to sound too harsh, but that's the simple truth, unless you're using another format than gif.

zuresh
03-20-2008, 09:37 AM
O. sorry it was my mistake.. sometimes I didn't checked well. :o anyway I didnt mean more than 256 colors in a single file's pellet though.

djr33
03-20-2008, 04:07 PM
Image Ready, among others, does allow for custom palettes, if that's what you mean, so you get the best 256 colors for your animation, not just the standard palette.