So... you put a graphic from a file into a Paradox "graphic" field and ...

.... what the ^@$@%#%?! ... it looks like an Impressionist painting ... by a
madman!

What happened, and what do you do about it?

EXPLANATION OF THE PROBLEM:
The root cause of this problem is that Paradox provides only 256 colors in
its "palettes." Palettes are a table of colors, indexed by number, which
identify all of the colors used on an image. Typical bitmaps and JPEGs
contain palettes with thousands or even tens of thousands of entries.
These must be squeezed down to 256... and if several bitmaps are on the
screen at the same time, all of them TOGETHER must be squeezed into this
color-space. (The process is called "quantizing.") Paradox is perfectly
awful at doing this.

WHAT DO YOU DO?
The solution is to pre-process images, using external tools, before you
import them into Paradox. You should convert them into Windows Bitmap
format and you should reduce the color-palette to less-than 256 colors.
Then import that image. Paradox won't have to do anything more to it,
which also avoids nasty problems in Paradox 8-10 that manifest when you try
to LoadFromFile() a bunch of JPG images in a row.

HOW CAN YOU DO IT?
I used the tool ImageMagick (http://www.imagemagick.org) which is a very
powerful, open-source graphic manipulation suite. It's free. I used the
"Convert" command-line program.

In ObjectPAL, the "Convert" program is run programmtically with a
command-line like this:
CONVERT -colors 128 -colorspace RGB foo.jpg BMP3:bar.bmp
... then loadFromFile("bar.bmp") and delete this temporary file.
("convert" is an ImageMagick program.)

WHY 128 COLORS?
The above example has boiled the color-palette on the image all the way down
to only 128 colors. That isn't a "magic" number, only a number that is
"quite a bit" less than 256. What I'm trying to do is to increase the
chances that Paradox will be able to display my image, and maybe several
images at a time, without having to /further/ re-map the colors that I'm
providing. I'm trying to improve the odds that it will have enough space
in its limited palette to fit all of my colors without having to quantize
any of them still further.

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Thanks, this was interesting info. I'll try this out.

Bitmap seems to look OK if they're in 100% size, but if you reduce the size
they look bad - on screen. On paper, however, Paradox seems to be able to
make them look good always.

Jostein Bakke

Jostein Bakke wrote:
Resizing, as I have seen it, does not seem to be a huge problem. But huge
palettes (a digital camera might generate an image with 64,000 entries) are
definitely a problem for Paradox (and Access, for that matter).

ImageMagick does a very good job of reducing the color-space, even such a
large jump as squeezing 64,000 colors down to 120. And once the colors
have been made "manageable," Paradox is fine with them. So it goes.

The goofy thing .. what had me puzzled for so long .. is that an /excess/ of
color information produces an output with /few/ useful colors.

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