[FFmpeg-devel] [PATCH] avfilter: add rawdump filter

[Eoff, Ullysses A]

> -----Original Message-----
> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf Of Nicolas George
> Sent: Wednesday, July 10, 2019 7:53 AM
> To: FFmpeg development discussions and patches <ffmpeg-devel at ffmpeg.org>
> Subject: Re: [FFmpeg-devel] [PATCH] avfilter: add rawdump filter
> 
> Eoff, Ullysses A (12019-07-10):
> > For the record, this "static" is a problem if multiple rawdump filters are
> > specified in the graph.  The initial reason for this was to open the file for
> > writing on the first init (to overwrite any pre-existing file), then open for
> > appending on successive reinit's (e.g. frame resolution changes).  Thus,
> > would need a better solution to achieve the same result without
> > influencing other instances of the filter.
> 
> The variable needs to be in the filter's private context, nothing more.
> 

Each time init is called (i.e. for reinit on resolution change), the private context is a
new instance.  On first init we want mode="w" for each rawdump filter in the
graph, but on reinit we want mode="a".  How do we achieve this when every
call to init passes a new private context instance.  I am not very familiar with
ffmpeg's programming API's, so maybe I'm missing something?

> Regards,
> 
> --
>   Nicolas George