According to msdk spec, there are two ways to enable filters:
1: Filters can be enabled by adding a filter ID
to mfxExtVPPDoUse. In this case, default filter parameters are used
2: Add filter configuration structures directly to mfxVideoParam.
Using 1 with 2 is optional but legal. Unfortunately it won't work
with some specific use cases like Detail/EdgeEnhancement.
Let's stick with option2 which works fine for all VPP operations.
https://bugzilla.gnome.org/show_bug.cgi?id=796468
Since we do the MSDK initializing in set_caps(), a FALSE
return may still cause the invokation of set_caps() again
and this will leads to buffer allocation and other mess-up.
So make sure the msdk initialized correctly before trying
to do any buffer allocation.
https://bugzilla.gnome.org/show_bug.cgi?id=796465
So far msdk produced dmabuf fds are non-mappable.
If user wants to download the content of underlined surfaces,
dmabufcapsfeature negotiated pipeline will fail. So if the input surface
is dmabuf and downstream doesn't have support for dmabuf capsfeatures,
we do the vpp (no passthrough) and produce the mappable videomemory
buffers.
https://bugzilla.gnome.org/show_bug.cgi?id=794946
