Converting an image with n-bit bit depth to a 16-bit bit depth image. (where 8 < n < 16)

I need to call the following IPP methods on an input image data.

• ippiColorToGray
• ippiLUTPalette
• ippiScale (just for 16 bit images)
• ippiCopy
• ippiSet
• ippiAlphaComp

I was using the 8-bit and 16 bit versions of this methods till now. But now we also allow 12 bit images as input. For ippiLUTPalette, I see that we can pass the bitSize that we are dealing with. But for the other API's we don't have it.

One approach I was thinking of trying out was to convert the images that has a bit depth falling between 8 and 16 bit to a 16 bit image and continue working on the result. I believe, ippiScale performs such conversions. But I couldn't find a flavor of it that works on bit depths other than 8, 16 & 32.

Is there a way to perform this conversion?

Or Is it possible to call the before mentioned APIs on images with bit depths other than 8 and 16 bits?