[FFmpeg-devel] [PATCH] nvenc: implement flush to help allow an encoder to be re-used

[Philip Langdale]

On Fri, 20 Dec 2019 16:07:18 -0800
Josh Allmann <joshua.allmann at gmail.com> wrote:

> One concern I had was about the long-term stability of this behavior.
> Right now, it works, but perhaps only coincidentally? Being flushable
> and resumable like this isn't explicitly part of the "contract" for
> nvenc, as far as I can see. Could future changes inadvertently
> introduce state that isn't reset in between flushes, breaking the
> resumable behavior? If so, is there a way to safeguard against that?
> 
> Josh

So, the behaviour at the ffmpeg level is something you can view as
stable. If it was to break, I'd expect us to fix it. For nvenc itself,
that's harder to make any statements about. I wouldn't expect the
nvidia folks to change thing casually, but until they document a
specific flush behaviour, there's always going to be a risk -
ultimately we just have to react if they change something.

In an ideal world, you'd have a test running for this, but we're not
set up to exercise any hwaccels in our automated fate executions.

Did this form of the patch work for you?

--phil