The previous code was not wrong, but I'd claim this makes the code more
robust. If a situation could happen in which the passed surface size is
incorrect, we could have passed a too small image, and
VdpOutputSurfaceGetBitsNative could have randomly overwritten memory.
Check the maximum size of video surfaces, and refuse initialization if
the video is too large for them.
Maybe we could do something more sophisticated, like inserting a
software scaler. On the other hand, this would have a very questionable
benefit, as it would be guaranteed to be too slow.
Instead of converting the hw surface to an image in the VO, provide a
generic way to convet hw surfaces, and use this in the screenshot code.
It's all relatively straightforward, except vdpau is being terrible. It
needs a huge chunk of new code, because copying back is not simple.
mpv supports two hardware decoding APIs on Linux: vdpau and vaapi. Each
of these has emulation wrappers. The wrappers are usually slower and
have fewer features than their native opposites. In particular the libva
vdpau driver is practically unmaintained.
Check the vendor string and print a warning if emulation is detected.
Checking vendor strings is a very stupid thing to do, but I find the
thought of people using an emulated API for no reason worse.
Also, make --hwdec=auto never use an API that is detected as emulated.
This doesn't work quite right yet, because once one API is loaded,
vo_opengl doesn't unload it, so no hardware decoding will be used if the
first probed API (usually vdpau) is rejected. But good enough.
We had some code for checking profiles earlier, which was removed in
commits 2508f38 and adfb71b. These commits mentioned that (working) hw
decoding was sometimes prevented due to profile checking, but I can't
find the samples anymore that showed this behavior. Also, I changed my
opinion, and I think checking the profiles is something that should be
done for better fallback to software decoding behavior.
The checks roughly follow VLC's vdpau profile checks, although we do
not check codec levels. (VLC's profile checks aren't necessarily
completely correct, but they're a welcome help anyway.)
Add a --vd-lavc-check-hw-profile option, which skips the profile check.
Formally, this sets the "background color" of the presentation queue.
But in practice, this color is also used as colorkey.
This commit doesn't change the VDPAU default yet.
Instead of generating vdpau_template.c with a Perl script, just include
the generated file in git. This is ok because it changes very rarely,
and the script is larger than the output it generates.
It also simplify the Makefile, and fixes the build. The problem was that
transitive dependencies do not work with generated files: there is no
dependency information yet when building it the first time. I overlooked
this because I didn't delete the .d files for testing (which contained
the correct dependencies, but only _after_ a first successful build).
