OpenMined <**Mail Free America**> wrote:
: If I wish to distribute animated graphics files, is there any other choice?

  Firstly, if you want to put gifs in your www page you'll have to pay quite
a lot of money to unisys (at least if you live in one of those countries).

  Secondly, 256-color animations are quite restricted. Of course there are
some things (like really flat cartoon animations) where 256 colors is enough,
but usually it isn't (eg. if you make a rendered animation with povray).
Rendered animations converted to gif usually look like crap.
  GIF doesn't support sound either.

: GIF, by the way, for some types of work, actually seems the SUPERIOR format,
: at least compared to JPG.

  Now you are comparing gif with an image format which doesn't support
animation.
  GIF is certainly crap compared to JPG or PNG (the choice between the two
depends on the type of image). With most images JPG, although lossy, gives
a very good quality with laughably small file sizes (specially when
compressing with the right parameter to avoid artifacts).

  I made a test to compare file sizes with the skyvase image (at 640x480)
in the standard povray distribution:

skyvase.gif      114 979
skyvase.jpg       57 453
skyvase.png      197 256
skyvase256.png    96 988

(The images can be found at
http://www.cs.tut.fi/~warp/skyvasetest/skyvase* (by specifying the explicit
name of the image).)

  It's interesting to note that the 256-color png image which (when
uncompressed) results pixel-by-pixel in the exact same image as the gif
image is quite smaller.
  The jpg image (with very high quality to avoid visible artifacts) is much
smaller than the gif image, even when it's a truecolor image.
  It's also interesting that even the truecolor png (which preserves
exactly the original image) is not unacceptably larger then the gif image
(of course it's much larger because it's lossless and it has to contain
24-bit colors instead of 8-bit colors, but still it's suprisingly small).

  The png image format also supports a lot more things that gif doesn't
(for example gif only supports 24-bit colors in its palette while png
supports up to 48-bit colors, gif supports one (1) transparent color while
png supports a whole alpha channel (which can be up to 16 bits deep) and so
on).
  What makes you say that gif is "superior" goes beyond me. Gif is just crap.

: When PNG becomes universal

  In which world do you live? What makes you think that png is not
"universal"? Which program does not support png (and don't bother
mentioning some 5 years old programs)?
  I would say that nowadays there are more programs (specially freeware ones)
that support png and don't support gif (because of the patent issues).

-- 
char*i="b[7FK@`3NB6>B:b3O6>:B:b3O6><`3:;8:6f733:>::b?7B>:>^B>C73;S1";
main(_,c,m){for(m=32;c=*i++-49;c&m?puts(""):m)for(_=(
c/4)&7;putchar(m),_--?m:(_=(1<<(c&3))-1,(m^=3)&3););}    /*- Warp -*/

Post a reply to this message