In article <web.3faef3a6513875ff5cd9832d0@news.povray.org>,
 "Tony LaVigne" <ton### [at] xenomechanicscom> wrote:

> I thought this would be a good idea for a couple of reasons. The first is
> that I'm under the impression a jpg can be compressed yet still maintain
> the same quality as bmp type file.  This is because I'm assuming;
> a) Default quality of a jpg is 80% (100% would be our bmp formated file)

Even a 100% JPEG loses information. JPEG2000 does allow lossless 
compression, however.


> b) each pixel of a jpg indexes a  rgb color map (assuming multi toned)

Incorrect. JPEG is not an indexed format.


> c) some pixels will have the same rgb value, so they use the same index to
> of the color map and that's why the jpg can be compressed, smaller in size
> than a bmp file.  Ideally there would be an option  for the quality of a
> jpg.

Not even close. I suggest you look up some information about the JPEG 
format.


> I also thought since it's so widely used it would make POVRAY that much more
> user friendly.  For instance I've found bmp's to be much more problematic
> for web pages.  Many of us have learned how to convert file formats but I
> remember starting out that it was one more hurdle that I had to get around.

There is simply no reason to put Windows BMP files on the web. There is 
really no reason to use the format at all, IMO. The best formats for 
this purpose would be either PNG for lossless images, or hand-tuned JPEG 
for small file sizes with good quality. POV-Ray has the ability to 
output PNG as well as several other lossless formats, and it is best to 
hand tune the compression of JPEG files.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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