I have it working :)))))
It turned out i had the image data in the wrong order.
image.mpData should not be RGB, RGB, RGB. But have first the complete red plane, then the green plane, and last the blue plane.
eg. If the image height and width both are 3 (very small just for this example.)
the byte input blob should look like:
R0 R1 R2 R3 R4 R5 R6 R7 R8 G0 G1 G2 G3 G4 G5 G6 G7 G8 B0 B1 B2 B3 B4 B5 B6 B7 B8
Ow, and 0,0 is the top-left of the image, also the float values of the image should be 0.000 - 1.000, dividing by 255 is correct. Other preprocessing is not needed.
Regards,
Richard