Hello,
I experimented with decoding "VDHA" pixel format, and to me it looks like packed 422 YUYV with 16 bits per component. Everything is fine except what might be lower 8 bits of precision are always filled with zero.
Is there a way?

Also, can I find Cineform-encoded test samples somewhere?

I may be wrong, but I believe Video for Windows is limited to 8-bit.
There are custom bypasses of strict Vfw use to get around this. The Cineform SDK is one for Cineform codec use. A lot of app support the direct Cineform SDK AFAIK.

VfW is a very old API. It has been depreciated since the mid 1990's.

This is just transparent data transfer between cfhd.dll and my program. There is no way for windows to know that something is happening and enforce any limits.
I am happy to use SDK, but there is some legal uncertainty
As I understand, SDK is activated by Cineform license which probably means purchasing Studio Premium.
Also, from reading older posts, permission to use SDK is not public.
These are two reasons I am looking into vfw first.