[FFmpeg-devel] [PATCH 0/1] ffmpeg: Switch cuvid to generic hwaccel

[Philip Langdale]

On Fri, 16 Jun 2017 21:53:22 +0200
wm4 <nfxjfg at googlemail.com> wrote:

> On Fri, 16 Jun 2017 20:31:14 +0200
> Timo Rothenpieler <timo at rothenpieler.org> wrote:
> 
> > Am 16.06.2017 um 16:41 schrieb Philip Langdale:  
> > > This is mechanically simple, but does the fact that additional
> > > command line arguments have to be used to get the same results
> > > count as a compatibility break? Do we need to fix that before we
> > > can actually make this change?    
> > 
> > I'd consider that as a breaking change, even though things don't 
> > "break", it results in unexpected behavior that is not obvious.  
> 
> Probably, but it's also slightly saner in general if you consider that
> a user could add video filters. Currently, hwaccel filters and normal
> filters are completely different beasts, so the user needs to be aware
> of the difference, and select the appropriate mode. So depending on
> whether you output hw surfaces by default, you'll break hw filters or
> sw filters by default. Making sure sw filters work by default seems
> like the better choice.
> 
> But yes, maybe we could rename the hwaccel just so that users of the
> old hwaccel become aware of the change. You could even keep the old
> hwaccel name, and make it somehow override the -hwaccel_output_format
> option and print a warning, in case you care enough for compatibility
> in this case.

We could use it as an opportunity to rename it to 'cuda' which is more
accurate.

Keeping the old specialised code for 'cuvid' would also ensure
compatibility :-)

--phil