Wasn't it Tony LaVigne who wrote:
>Marty wrote:
>>is image output direct to jpg going to be an option in the next release
>>of povray?
>>
>
>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)
>b) each pixel of a jpg indexes a  rgb color map (assuming multi toned)
>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.
>
>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 now support for lossless compression in the JPEG image format,
but there's very little support for it at the moment. In particular
Internet Explorer can't display lossless JPEGs, so don't use them on web
pages.

The concept of "100%" quality in the standard JPEG format is misleading,
it does not mean that the image is lossless. In the tests that I did, a
lossless JPEG tended to have a file size that was twice the size of a
"100% quality" JPEG, and there were differences in the images
particularly at sharp edges.

I'd suggest the use of PNG images. These are supported by all the major
web browsers, are lossless, and POVRay can output them.

-- 
Mike Williams
Gentleman of Leisure

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