13 replies to this topic

[dual]

Someone sent me a great piece of art, rfaworld, but I lost the contributor's name while sorting my deluge of email. I'm pretty sure it was hacnslash or Access Excess, but please let me know so I can give proper credit.

[hacnslash]

it was me.........no problem i can send it to you again if you loose it......

[dual]

I grabbed the png, deleted the email and then my memory failed me again... Thanks.

[hacnslash]

No prob, also, sorry for the big ass png file, but jpeg would screw with the texture too much, so I decided to just leave it like that......

[ntheory]

Wouldn't it be nice if there were a mixed lossy/losslessly compressed image format? I dunno, I think so because I've run into that same problem before.

The image encoder could either try to be smart about it and do it automatically or the artist could specify it with some very basic lasso-like tool. Might be nice...

[hacnslash]

well, it would kick ass if we had compression tech that would make 600 meg isos 20 meg files, that would be serious compression. Images need better formats, and there are so many, and none of them do compression very well, actually they compress, but they lose image quality, so yes there is need for a new format.... who knows.....hey, at least I used png, not bmp......lol

[ntheory]

::whew::

It be more efficient to snail mail it to dual on punch cards than use BMP.

We had a PowerPoint file at work that was 107MB because it had about 15 800x600 images in it (which were originally JPEGs). I have a feeling MS converts them to BMPs when it saves... horrible. Only MS would decide they need to losslessly compress a lossy image.

[hacnslash]

lmao, punch cards, my dad used to have a stack o those!!! oh well. yeah, 107 meg pp file, wow, thats why i stick to openoffice (altho the fonts piss me off, they look xtremely weird in writer)

[ChZ]

I'd think that the problem with an image format that allowed mixing lossless/lossy compression would be that the artifacts in the lossy part of the image would make the lossless part look weird. Have you tried lowering the JPEG compression level? That'll make it look a lot better. PNG really doesn't perform well on photo type images.

[hacnslash]

in a sort of related post..........i used 5 for the png compression, and its not really a photo-type pic, you'll see it when dual puts it up, and indeed I found that png does not work well with photos, it goes along fine with drawing-type pics... and I think that for a format to be succesful it should be lossless and it should be small, I do not want any lossy type shit in my 5 megapixel photo of my dog snookums wearing that pink tutu....ok, I need some caffeine........as I Chz saying, the lossy part of the format would make the lossless part look bad, it wouldnt look lossless anymore.lol. But I guess there could be a format that compresses without loss, it shouldnt be that impossible......

[ChZ]

The compression level should be set to the highest possible level if you're planning on releasing it. The only difference between a low compression level for png and a high compression level is that the high compression level takes longer to save and results in a smaller file size. PNG's lossless, so don't worry about the compression level affecting the image quality.

Lossy compression is a good thing since it can achieve smaller file sizes than a lossless compression algorithm could ever dream of. So what if you lose some image information and some pixels are slightly off color? If the compression level isn't set to some ridiculous level, your eyes probably won't be able to tell the difference.

JPEG info:
http://catcode.com/imgguide/lossy.html
http://www.ece.purdu...t/jpegtut1.html
http://www.theimage....sjpg/gif2A.html

PNG info:
http://www.libpng.org/pub/png/

[ntheory]

I'd think that the problem with an image format that allowed mixing lossless/lossy compression would be that the artifacts in the lossy part of the image would make the lossless part look weird.

Yeah, you'd have to go through great pains to get it right. But I think if the encoder is smart enough it'd be possible. I wish JPEG at least had a non-fixed quantization level. I think JPEG2000 supports variable quantization though, that'll fix your problem 99.9% of the time.

[White_Raven]

Well one thing you need to remember is that graphix type compression make use of special quirks in the data itself that is relitive to grohix only.. what we need is a iso compression type that mathimaticly takes advantage of the iso format.

[hacnslash]

ChZ, thanks for clearing that out, I didn't know png was lossless.....oops, next time, i'll compress it at maximum....