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I took 6 screenshots from Ninja Gaiden, as produced by a MEKA capture.

PCX Total: 112.915 bytes

Converted to GIF using "ACDSee 3.1": 41.770 bytes
Then optimized with "Advanced GIF Optimizer 4.0.12" : 36.478 bytes

Back to original PCX files, converted to PNG using "ACDSee 3.1": 20.220 bytes
Optimized using pngout.exe (a great tool that Maxim recommended me, downloadable here): 13.419 bytes.

pngout.exe is a slow tool, so it took approximately 1 minute to optimize all 6 files. For a high-res scan (~2000x2000), it's in the range of 5/10 minutes on my 600 Mhz computer.

In any cases, PNG seems to rule over GIF for screenshots.
Also, palette precision in PNG seems to be better (GIF lose some subtle nuance).

So we'll use PNG for screenshots. Unless someone come and tell me that PNG is not supported with a widely used web browser ?

If you are curious:
http://wip.smspower.org/tests/image-compression/

Quote

> So we'll use PNG for screenshots. Unless someone come and tell me that PNG is not supported with a widely used web browser ?

*cough* Internet Explorer. It tends to badly handle gamma information stored in files. I think PNGout removes this anyway, so maybe it doesn't matter. Try comparing actual pixel colour values.

Demo:

I made this ages ago and deliberately set the background to the forum background colour of #006699. In IE it appears darker.

Maxim

Quote

> *cough* Internet Explorer. It tends to badly handle gamma information stored in files. I think PNGout removes this anyway, so maybe it doesn't matter. Try comparing actual pixel colour values.

There's nothing we can do. But anyway it is harmless as the original data are unmodified (There's nothing we can do either if one user darken his screen or something..., it's similar). Now if IE gets fixed someday that'll be good but we do not depend on that and the eye difference is not dramatic.

The problem is only really bothering when using transparent PNG or when using a same color outside of the PNG. Most pictures are scans or screenshots, which are all rectangle pictures and do not relate with our site color.

Author	Message
Bock Site Admin Joined: 08 Jul 2001 Posts: 8661 Location: Paris, France	PNG/GIF comparaison Posted: Wed Feb 18, 2004 10:43 am
	I took 6 screenshots from Ninja Gaiden, as produced by a MEKA capture. PCX Total: 112.915 bytes Converted to GIF using "ACDSee 3.1": 41.770 bytes Then optimized with "Advanced GIF Optimizer 4.0.12" : 36.478 bytes Back to original PCX files, converted to PNG using "ACDSee 3.1": 20.220 bytes Optimized using pngout.exe (a great tool that Maxim recommended me, downloadable here): 13.419 bytes. pngout.exe is a slow tool, so it took approximately 1 minute to optimize all 6 files. For a high-res scan (~2000x2000), it's in the range of 5/10 minutes on my 600 Mhz computer. In any cases, PNG seems to rule over GIF for screenshots. Also, palette precision in PNG seems to be better (GIF lose some subtle nuance). So we'll use PNG for screenshots. Unless someone come and tell me that PNG is not supported with a widely used web browser ?

Bock Site Admin Joined: 08 Jul 2001 Posts: 8661 Location: Paris, France	Re: PNG/GIF comparaison files Posted: Wed Feb 18, 2004 10:54 am
	If you are curious: http://wip.smspower.org/tests/image-compression/

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14755 Location: London	The downside of PNG Posted: Wed Feb 18, 2004 1:27 pm
	Quote > So we'll use PNG for screenshots. Unless someone come and tell me that PNG is not supported with a widely used web browser ? cough Internet Explorer. It tends to badly handle gamma information stored in files. I think PNGout removes this anyway, so maybe it doesn't matter. Try comparing actual pixel colour values. Demo: I made this ages ago and deliberately set the background to the forum background colour of #006699. In IE it appears darker. Maxim

Bock Site Admin Joined: 08 Jul 2001 Posts: 8661 Location: Paris, France	Answer Posted: Mon Mar 01, 2004 5:44 pm
	Quote > cough Internet Explorer. It tends to badly handle gamma information stored in files. I think PNGout removes this anyway, so maybe it doesn't matter. Try comparing actual pixel colour values. There's nothing we can do. But anyway it is harmless as the original data are unmodified (There's nothing we can do either if one user darken his screen or something..., it's similar). Now if IE gets fixed someday that'll be good but we do not depend on that and the eye difference is not dramatic. The problem is only really bothering when using transparent PNG or when using a same color outside of the PNG. Most pictures are scans or screenshots, which are all rectangle pictures and do not relate with our site color.

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