🚀 go-pugleaf

Hi everybody,

I'm trying to code a small program that extract an object from a
picture.
For that, I coded somes functions in order to grab pictures from my
webcam (using VFW).
This program works fine BUT the obtained image is a DIB with 16
millions colors.
I need images with only 256 colors.
I tried to use the the macro capSetVideoFormat in order to force my
webcam (Dexxa) to use the following format :
    bi.bmiHeader.biWidth = 320;
    bi.bmiHeader.biHeight = 240;
    bi.bmiHeader.biPlanes = 1;            // This value must be set to
1.
    bi.bmiHeader.biBitCount = 8;          // 256 couleurs
    bi.bmiHeader.biCompression = BI_RGB;  // No compression
    bi.bmiHeader.biSizeImage = 0;         // Set to 0 for BI_RGB
bitmaps.
    bi.bmiHeader.biXPelsPerMeter = 1;
    bi.bmiHeader.biYPelsPerMeter = 1;
    bi.bmiHeader.biClrUsed = 0;           // All colors are used
    bi.bmiHeader.biClrImportant = 0;      // All are important
    if( capSetVideoFormat(CaptureWindow,&bi,sizeof(BITMAPINFO)) ==
true)
    ...
but when I run the preview, I got the error 418 : Unknown format => I
guess the driver of my webcam is not able to handle a such format.
===> If you have an idea... (thanks)

OK, don't matter, I have a picture (not exactly what I want but, for
the moment ... :o) ). Now, because I really need 256 colors, I would
like to know how to decrease the number of colors of the bitmap in
order to "build" a palette. I need this palette to build an histogram
that will be used in the extraction.
Is there somebody who know how to do ?
Thanks a lot for your support.

Neurone66