I have been testing a free program for making JPEG2000 files from BMPs and
converting them back to BMP (to see how the compression turns out). This
program is based on the first draft of the JPEG2000 specifications... and I
must say that I am thoroughly impressed. Here are some of my results:

FORMAT    COMPRESSION    SIZE      QUALITY

(YAHI 640x480)
 BMP          -          900kb        -
 PNG          -          489kb        -
 JPG         ~0%         234kb     No perceivable quality loss
 JP2          0%         341kb     No perceivable quality loss
 JP2         10%          90kb     Some JPEGness becoming visible
 JP2         20%          45kb     Some areas become blurry and JPEGy
 JP2         30%          30kb     More blurriness and JPEGness visible
 JP2         40%          23kb     and
 JP2         50%          18kb     so
 JP2         60%          15kb     on...
 JP2         70%          13kb     ...
 JP2         80%          11kb     ...
 JP2         90%          10kb     ...
 JP2        100%           9kb     Looks like when I take my glasses off

(Abstrahere 1400x1050)
 BMP          -         4307kb        -
 PNG          -         1473kb        -
 JPG         ~0%         857kb     No perceivable quality loss
 JP2          0%        1255kb     No perceivable quality loss
 JP2         10%         430kb     No perceivable quality loss
 JP2         20%         215kb     Very slight changes in some areas
 JP2         30%         143kb     Some JPEGness in areas without much
detail
 JP2         40%         107kb     More of the above, with slight JPEGness
in areas with detail
 JP2         50%          86kb     and
 JP2         60%          72kb     so
 JP2         70%          62kb     on...
 JP2         80%          54kb     ...
 JP2         90%          48kb     ...
 JP2        100%          43kb     Lots of blurriness in some areas, others
very sharp
                                   (the more detail, the sharper it is)

I hope someone finds this useful/interesting. I know I do. I can't wait till
this gets integrated into Internet applications. :)

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