Problem about cudaCreateChannelDesc

Dear all,
I have some question about cudaCreateChannelDesc,I have read the CUDA_runtime_api.h.What does x,y,z,w mean?
Is it the bit depth?
If a bmp file ,so I read the API like cudaCreateChannelDesc(8,8,8,8,cudaChannelFormatKindUnsigned),because all RGB and alpha channel are 8 bits.
So if the data is 10 or 12 bit,I can run the API lik cudaCreateChannelDsec(10,10,10,10,cudaChannelFormatKindUnsigned)?

[url]http://docs.nvidia.com/cuda/cuda-runtime-api/group__CUDART__HIGHLEVEL.html#group__CUDART__HIGHLEVEL_1g655725c27d8ffe75accb9b531ecf2d15[/url]

If you search for it in the cuda programming guide, you can find several examples.

There are also cuda sample codes which provide examples.

Is there any clear explanation?The CUDA_Runtime_API.pdf in 229 page write (x —— x component)。So does it mean bit depth?

Did you click on the link I gave? It says:

“Returns a channel descriptor with format f and number of bits of each component x, y, z, and w.”