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A satisfied customer
- On another graphics forum I pointed out that the PNGout plugin for IrfanView has a nice GUI and compresses better than pngcrush. This was the response:
"Oh wow... I tried out the PNGout and... just wow."
On a different point, I noticed something unexpected and did a search of this forum to see if it had been mentioned before. PNGout generates a different palette order if I start with a 24 bit BMP image than if I start with a PNG created by Web Image Guru. Consequently, the two resulting output file sizes are different. The original palette order in Web Image Guru's PNG was different to both PNGout versions. How come?Edited at - Thanks for the free advertising : )
Short answer: If you run pngout by specifying the /c3 option explicitly, the palettes will match. There are actually 3 ways to specify palette order in PNGOUT and PNGOUTWin. Study this chart:PNGOUTWin: PNGOUT: Description:
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1. Optimize pngout .. Starts with palette from file if paletted; inconsistent output
2. Regenerate pngout /c3 .. Regenerates palette from scratch - consistent output
3. Preserve pngout /kp .. Doesn't modify palette. Uses method #1 or #2 if no palette
The PNG from Web Image Guru must be a paletted image. The default is optimize, where PNGOUT tries to re-order palette entries to save on Huffman table storage. Re: A satisfied customer
When using /c3 /kp, /kp takes priority, right?- It's easy enough to test with file compare. The answer is yes.