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I have recently fount that .NET 2.0 will not convert to a grayscale 8 bit pixel format out of the box...

It seems that the Swift Decoder Demonstrator application that comes with the sd2.dll does this by using ImageConver.dll...  However,,, no documentation was provided on how to use this ImageConvert.dll...

Is this documentation availiable???  If so,,, where???

Thanks...

We do not provide documentation for the ImageConvert.dll.  For information and code on how to convert an image to grayscale using .NET try this link.

Yeah,,, already tried that...  The key word here is "indexed"...  The link you provided converts to grayscale,,, sure,,, but is VERY slow,,, and is not indexed...  The resulting image still will not work with your software...  There are ways to do this unmanaged to increase performance by an order of magnitude (literally) using bit shifting,,, but still,,, the end result is grayscale,,, not 8 bits per pixel indexed grayscale...

ok,,, got it...

Had to first convert to gray using bit shifting...

Then used a graphics object to redraw as PixelFormat.Format8bppIndexed...

Then save to a bmp file...

The only problem I see now is the large size of the bmp created...  I m sure I can get this to a reasonable size though...

Z

Nope,,, I was wrong...  Forgot that the test app does convertion to gray and indexed for you...

Still getting the same error...

"A Graphics object cannot be created from an image that has an indexed pixel format."

This stops me from being able to create the required format from a jpg in .NET...

Any more ideas???

Thanks...

What I have done in the past is to create a secondary image where the converted data will be placed:

System.Drawing.Imaging.BitmapData bmd = image.LockBits(new System.Drawing.Rectangle(0, 0, frame.Width, frame.Height), System.Drawing.Imaging.ImageLockMode.WriteOnly, imageFormat);

 /* Write grayscale image contents into image from original image */

return image;