Image compression

[stormbind]

I've been working on a replacement avatar. The British shield is a temp, but having real problems

Edit: The new shield is also a temp. I don't like the white border

It's 65x65 pixels but greater than 4096 bytes so I cannot upload it to the forums.

Ofcourse, GIF are restricted to 256 colours and such a file does fit but even if this looks alright in the image editors, the resulting file is missing key colours (in the yellow band)

I have tried dithering and patterning, but they didn't help solve the missing colour problem.

Have also tried variable compression methods using JPG and PNG, but end results are greater than 4096 bytes.



Any tips would be much appreciated

 

[CrackedCrystal]

What do you mean if it looks OK in the editor, it is missing key colors? Do you mean it loses it colors after uploading it to CFC?

Prehaps you set an invisible color as yellow?

 

[DiamondzAndGunz]

When you edit the image, it has all of the colors available (over 256). When you export it to a gif file, it has to lose some of those extra colors, since a gif is limited at 256.

Perhaps you could try cutting out some colors that are less noticable?

 

[stormbind]

No, I converted it to 256 colours in the editor (because it gives options like patter/dither/none) and it looked fine... but after saving as a GIF, the yellow was turned to red

Not unlike saving a truecolour file as a GIF

I don't normally have this problem and don't blaim the editor (although, every editor has it's quirks), it seems to be the mix of colours in the image which is why I tried JPG and PNG file formats - which are not restricted to any pallet.

But I couldn't get JPG/PNG files down to 4096 bytes, even if I reduced the colours before saving

 

[stormbind]

Originally posted by DiamondzAndGunz
Perhaps you could try cutting out some colors that are less noticable?

I can reduce it to 128 colours without great loss in detail, and if saved as a PNG the end result looks right... but still too large. [PNG seems to be best for images that have large square chunks of the same colour(s) which this doesn't]

 

[stormbind]

Originally posted by CrackedCrystal
Prehaps you set an invisible color as yellow?

Nope

 

[CrackedCrystal]

That is weird. I just did a count. My avatar is 2844 colors (so 32K color pallete) and only 2K in size as a jpg. 65x48 pixels.

EDIT: it must be how jpg does compression. I have alot of green in mine. Also, mine is a little smaller but not by more than a third

 

[Jeratain]

If you're using Photoshop or Image Ready:

Click "Save for web" then choose the jpeg format. Then lower the quality to about 80. Check the bit size on it. It should be small enough.

 

[stormbind]

Have now saved it as a highly compressed JPEG. It's gone blurry and I cannot make the corners transparent - but it's now down to size

If there's a better way of compressing it, or an application that can do a better job I would like to know about it. Thanks

 

[damunzy]

Looks good to me.

 

[damunzy]

wow, major change since I read this thread and when I posted.

 

[stormbind]

Originally posted by munzy
Looks good to me.

Actually, I can only guess at what it looks like... something blew in my PC and now I don't see all the colours that I should

Not sure if the graphics card or monitor, think it's the card (because there are representatives of Red, Green and Blue being displayed).

Many shades are missing
Examples:
0,0,255 looks like 0,0,0
255,0,255 looks like 255,0,0
But I still see many shaded of blue, weird huh?

I'll prolly replace the card and then if the image isn't what I expected
(It has happened when I look at an image from another PC - new detail that shouldn't have been there had gone unoticed because that shade of colour hadn't shown up on my PC)

 

[Jeratain]

If you want, post the original image and I'll compress it for you without losing too much quality.

 

[stormbind]

I just looked at it on another PC and it's much brighter than I thought but otherwise the same.

Thanks for the offer Jeratain but I would like to know how to do it myself because I may edit the image.

 

[Lucky]

Well, just using your avatar now, you can create a GIF at a reduced number of colors (124) which looks (almost) the same as the JPG and you have your transparency.

-

Not sure about that upper right corner, but I left it as is.
Hmm, now that I look at it I see that´s a TM. Breaking copyrights, are you?!

Anyway, that GIF is at 4087 Byte.

 

[Praetorian]

Looks good to me

 

[stormbind]

Cheers lucky!

btw, which app did you use to save it?

 

[Lucky]

LView Pro, but it doesn´t matter. Everything a little better than Paint(brush) can do that.