[FFmpeg-devel] [PATCH] avcodec: remove old vdpau decoder implementation

[Philip Langdale]

On Sun, 4 Oct 2015 09:25:23 -0400
compn <tempn at mi.rr.com> wrote:

> carl: if this new api works with kodi and mplayer, whats the problem?
> 
> are there still users of this api in 2015? yes or no?
> 
> carl, do you use this api? what for? to test vdpau?

I'm curious about this too. Traditionally, mplayer *is* the long
tail of api usage, and even it was updated to use the new API a long
time ago. The change I made recently simply removed some usage of old
API structs to carry new API data, and that was a trivial cleanup - it
has not been possible to use the actual old API for a long time.

While hwaccel is still confusing from the client side, the
implementation inside avcodec is far far superior, as wm4 says. When I
added hevc vdpau support, I simply had to implement the hwaccel hooks
and make one change in the hevc parser to expose one metadata item. I
didn't need to touch anything else. I can only imagine how horrible it
would have been to make work in the old API - needing to work out how
to expose the parser separate from the decoding logic and all the other
messy things that the other codecs had to deal with.

There is a non-trivial cost associated with keeping all those
convoluted #ifdefs, and I think the reality is that those costs were
actually not being paid - meaning that the old API probably didn't
work, given that no application, that I'm aware of, was using it. Not
mplayer, not kodi, not vlc, not ffmpeg-vdpau.c. And there's no FATE for
it either (or the new one, of course).

> carl is maintainer of this vdpau code, wm4.
> its right there in MAINTAINERS.

As am I, for better or worse.

Perhaps Carl and I can talk about this at the GSoC summit. I support
this clean up, but I'd also like Carl to be on-board with it.

Thanks,

--phil