PNG compression levels

I need to save some files a PNG.  Never having used PNG 
before, I'm a bit unsure about the meaning of compression 
level.

Is it true that PNG is completely lossless regardless of the 
compression level, and that compression level only determines 
how fast or slow a file will be to save and open?   Is that 
the only consideration for PNG compression levels?


-- 
Joe
http://www.joekaz.net/
http://www.cafeshops.com/joekaz


0
Joe
11/26/2003 9:27:57 PM
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Joe <nospam@joekaz.net> wrote:
> I need to save some files a PNG.  Never having used PNG 
> before, I'm a bit unsure about the meaning of compression 
> level.
> 
> Is it true that PNG is completely lossless regardless of the 
> compression level, and that compression level only determines 
> how fast or slow a file will be to save and open?   Is that 
> the only consideration for PNG compression levels?

Yes, yes and yes.

Of course it takes a tad longer to compress an image with the higher
compression levels, but recent computers really are fast ernough
to always compress using the highest compression level. You won't notice
the difference in time.

Bye,
       Simon
-- 
      Simon.Budig@unix-ag.org       http://www.home.unix-ag.org/simon/
0
Simon
11/26/2003 9:38:41 PM
In <3fc52b6f@si-nic.hrz.uni-siegen.de>, Simon Budig wrote:

>> Is it true that PNG is completely lossless regardless of the 
>> compression level, and that compression level only determines 
>> how fast or slow a file will be to save and open?   Is that 
>> the only consideration for PNG compression levels?
> 
> Yes, yes and yes.

I want to add that *opening* a PNG with high(est) compression level isn't
slower than one with low(est) compression level.  It just affects the
speed of the compression.

Ciao,
	Marc 'BlackJack' Rintsch
0
Marc
11/28/2003 10:48:39 PM
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