Sure, You get a byte stream from a webCam, & you'd like to display said image. Correct? Well, I'll assume that your data is pointed to by *rawData and that the lines aren't padded (each horizontal line of the image consumes width*3 bytes) wouldn't you just start-out by writing a few functions that will allow you to get all of the pixels one-by-one and insert them into a HBITMAP object? As a start, how about something to get pixel values (watch for endianess)
COLORREF getPixelFromRawData(int x, int y)
{
char *data, r, g, b;
long index;
data = rawData;
index = (y\*widthPixels\*3) + (x\*3)
r = data\[index+0\];
g = data\[index+1\];
b = data\[index+2\];
return RGB(r,g,b)
}