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1. 

   BIGBEN
   Member

   One very strange thing happens when I try to optimize my GIF's.
   Most of them are optimized very well with your tool, but all of the outgoing PNG's are with 256-color pallete (the ACDSee say they are), even before I had a 64-color gif.
   I ask because even 2-colored after optimization are saved as 256-color. And some of them are bigger than original GIF's.
   Is everything OK?
   
   And when I go to file->properties it is always 8-bit image even if original GIG was 1 bit image.
   When I try to change bit depth reduction less than 8-bit the file isn't written.
   But sometimes if I try to write 6-bit depth Gif file with 1-bit depth reduction option enabled, it outputs me the file with... 8-bit depth again.
   
   What's wrong? Maybe I miss something, all the output PNG's are 8-bit depth, I tried different options, but they do not help.
   
   I can mail you these files, if you want to.
   I have one 64-colored Gif image that is smaller than output PNG and some 2-colored.
   
   Thanks for great, no GREAT program!
   
   Is PNG always SHOULD BE smaller than GIF?
   
   Regards, Benjamin ( you know this guy, don't you ;) )

   Posted 5 years ago #
2. 

   counting_pine
   Member

   When PNGOut converts GIFs, it defaults to 8-bit. The latest version of PNGOut will output at the smallest possible bit depth if you put /d0 on the command line, but PNGGauntlet seems to come with an earlier version that doesn't support this, so if you select Bit Depth Reduction: Minimize, it will have no effect, and GIFs will be converted to 8-bit.
   
   If you want to convert GIFs to a smaller bit depth, you will have to either specifically choose the bit depth you want or download the latest version of pngout.exe from Ken Silverman's utility page.
   
   Any 64-colour GIFs will still have to be converted to 8-bit, though. The PNG format only allows bit depths of 1, 2, 4 and 8 for palette images, providing up to 2, 4, 16 and 256 colours, respectively. So a 64-colour image needs to be converted to 8-bit.
   
   

   BIGBEN wrote:

   Is PNG always SHOULD BE smaller than GIF?

   
   Short answer:
   No.
   
   Long answer:
   PNG is usually smaller than GIF, but:
   - With very small images, GIF is smaller than PNG because its format has less size overhead
   - PNG uses a different type of compression which is usually, but not always, more effective
   - With certain palette sizes, GIF can use a lower bit depth than PNG, so the uncompressed image is smaller. For example, your 64-colour image can have a bit depth of 6 with GIF, but needs a bit depth of 8 in PNG

   Posted 5 years ago #
3. 

   BIGBEN
   Member

   Thank you for your answer. Especially about bitdepth.
   I will keep it in my mind when optimizing resource files for my PocketPC game http://www.wildgames.net
   I'm not a command promt lover so I'll use PNGGauntlet anyway.
   Thanks again

   Posted 5 years ago #
4. 

   counting_pine
   Member

   BIGBEN wrote:

   I'm not a command promt lover so I'll use PNGGauntlet anyway

   
   OK, that's fine. But PNGGauntlet uses pngout.exe to do its PNG compression, so if you want to use the Minimum Bit Depth option in PNGGauntlet, you'll have to either wait for a new version of PNGGauntlet with a later version of pngout.exe, or download the latest pngout.exe from here and overwrite the one included with PNGGauntlet. On my computer it's in "C:\Program Files\PNGGauntlet\support".

   Posted 5 years ago #
5. 

   brh
   Key Master

   Wow, I wish somebody had told me sooner - looks like I had made a mistake packaging the installer, and I didn't notice because I always run the debug version. My bad. I've uploaded a new version of PNGGauntlet that includes the latest PNGOUT.

   Posted 5 years ago #
6. 

   BIGBEN
   Member

   Thank you :P

   Posted 5 years ago #

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