Hey there,
I just wanted to point out that the "crunching" done on our pngs produces files that have forced alpha channels. Obviously if the image needs transparency, no harm there. However, for things that should have no opacity (such as screenshots), it can end up bloating them more than they need to be.
Also, I found something that compresses better than pngcrush (however, it is MUCH slower). It's called "pngout", it's cross-platform, it's free, but it is not open source. I'm going to be re-compressing all of our screenshots with it because the results are much better (imho). However, I want to make sure that we get someone with IE to check that they view fine there before proceeding. They do load okay in Opera 10, Firefox 3.5, and everything else that I checked.
A comparison of the 0.47 "spiro" screenshot was as follows:
355726 - Version currently on server 349063 - Saved from GIMP with the unnecessary alpha channel removed 337597 - Compressed w/ pngcrush (brute option) 327638 - Compressed w/ pngout (RGB color option)
28k is 28k... better for serving and receiving. In the end, doing this to all of our screenshots will probably add up to quite a bit.
If anyone is interested in using pngout, it can be obtained here: http://advsys.net/ken/utils.htm
Note: Someone else ported it to Linux, OSX, and BSD... so you'll need to follow a link on that page to the next place.
Cheers, Josh
On 08/09/09 01:08, Joshua A. Andler wrote: <snip />
Also, I found something that compresses better than pngcrush (however, it is MUCH slower). It's called "pngout", it's cross-platform, it's free, but it is not open source. I'm going to be re-compressing all of our screenshots with it because the results are much better (imho). However, I want to make sure that we get someone with IE to check that they view fine there before proceeding. They do load okay in Opera 10, Firefox 3.5, and everything else that I checked.
Just FYI and in case, I use a great little cli tool called pngnq to compress pngs. Works great, very significant compression ratios. It's in the debian/ubuntu repos (sudo apt-get install pngnq).
Here's the homepage: http://pngnq.sourceforge.net/
HTH
Al
Alan Lord (News) wrote:
On 08/09/09 01:08, Joshua A. Andler wrote:
<snip /> > Also, I found something that compresses better than pngcrush (however, > it is MUCH slower). It's called "pngout", it's cross-platform, it's > free, but it is not open source. I'm going to be re-compressing all of > our screenshots with it because the results are much better (imho). > However, I want to make sure that we get someone with IE to check that > they view fine there before proceeding. They do load okay in Opera 10, > Firefox 3.5, and everything else that I checked.
Just FYI and in case, I use a great little cli tool called pngnq to compress pngs. Works great, very significant compression ratios. It's in the debian/ubuntu repos (sudo apt-get install pngnq).
Here's the homepage: http://pngnq.sourceforge.net/
Interesting tool! However, if anyone is going to use this on screenshots or whatever, please keep in mind that this tool is lossy (that is, it reduces the number of colors used and therefore you generally lose some information). From what I see on the site it gives pretty nice results, but for screenshots that show off Inkscape (and/or artwork generated by Inkscape) it might not be appropriate.
On Tue, 2009-09-08 at 10:01 +0200, Jasper van de Gronde wrote:
Alan Lord (News) wrote:
On 08/09/09 01:08, Joshua A. Andler wrote:
<snip /> > Also, I found something that compresses better than pngcrush (however, > it is MUCH slower). It's called "pngout", it's cross-platform, it's > free, but it is not open source. I'm going to be re-compressing all of > our screenshots with it because the results are much better (imho). > However, I want to make sure that we get someone with IE to check that > they view fine there before proceeding. They do load okay in Opera 10, > Firefox 3.5, and everything else that I checked.
Just FYI and in case, I use a great little cli tool called pngnq to compress pngs. Works great, very significant compression ratios. It's in the debian/ubuntu repos (sudo apt-get install pngnq).
Here's the homepage: http://pngnq.sourceforge.net/
Interesting tool! However, if anyone is going to use this on screenshots or whatever, please keep in mind that this tool is lossy (that is, it reduces the number of colors used and therefore you generally lose some information). From what I see on the site it gives pretty nice results, but for screenshots that show off Inkscape (and/or artwork generated by Inkscape) it might not be appropriate.
No way I would use it if it was going to be lossy (at least I don't use settings that would cause any visual difference). And yes... I have compared side by side and there is no difference.
Cheers, Josh
participants (3)
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Alan Lord (News) -
Jasper van de Gronde -
Joshua A. Andler