Translating I420_10LE to P010 in wg_parser_get_preferred_format() would achieve the same thing on the win32 side, just in a more declarative way.
I'm happy with that. I meant I'd prefer to offer P010 rather than skip adding the preferred format.
To be clear, "preferred format" is exclusively a winegstreamer concept, not a win32 concept nor a GStreamer concept.
I guess the parallel I'm drawing is from the following line in the documentation for [IMFTransform::GetOutputAvailableType](https://learn.microsoft.com/en-us/windows/win32/api/mftransform/nf-mftransfo...): _The MFT defines a list of available media types for each output stream and orders them by preference._
P010 is offered as the first option on Windows for the video I'm testing; and that's the behavior I wanted to keep. Although, my motive for that was in case an application was dependent on that behavior, but it looks like that list is only available through the MFT interface anyway (i.e. it's not mirrored by the IMFSourceReader interface for example, which only offers the native types), so maybe it's not so important.
There are a couple reasons that I didn't use GUIDs ...
OK, that makes sense. Thank you.
This is pretty much the problem, and it needs to be changed.
I agree, we want to match Windows behavior where we can, but I don't think that change is within the scope of this MR.
So given my only motive for translating I420_10LE to P010 seems moot (as that behavior on Windows is in the AV1 decoder MFT, which we don't have), maybe just skipping the preferred format if it's UNKNOWN is the best option?