Creating Developer Defined BitmapPalette for 16-Bit Grayscale Image

Hi,
Wondering, if someone else knows/can help?
 
I am looking for a way to use a custom palette with 16-bit grayscale image data. I am looking to remap the pixels for display only (so can see normally image features that are too dark). I want to use the palette to avoid looping through all of the millions of pixels in the image (which does not meet my performance desires).
 
This code displays the 16-bit grayscale image correctly.

            PixelFormat pf = PixelFormats.Gray16; //int rawStride = ((width * pf.BitsPerPixel) + 7) / 8; // Create a BitmapSource.            BitmapPalette palette = BitmapPalettes.Gray16;
            BitmapSource bitmap = BitmapSource.Create(
                width, 
                height,96, // 96 is dpi for X and Y96, 
                pf, 
                palette, 
                pixelData, 
                rawStride); return bitmap;

 
It seems to ignore a new custom palette (not in above code) unless I make the

PixelFormat pf = PixelFormats.Indexed<4|8>

but I do not see a PixelFormats.Indexed16 for 16-bit support.
 
Thanks for looking!