[FFmpeg-devel] [PATCH] avcodec/qsvenc: fix version detection on cygwin

[Li, Zhong]

> -----Original Message-----
> From: ffmpeg-devel [mailto:ffmpeg-devel-bounces at ffmpeg.org] On Behalf
> Of Mark Thompson
> Sent: Sunday, June 17, 2018 11:48 PM
> To: ffmpeg-devel at ffmpeg.org
> Subject: Re: [FFmpeg-devel] [PATCH] avcodec/qsvenc: fix version detection
> on cygwin
> 
> On 15/06/18 15:52, Timo Rothenpieler wrote:
> > ---
> >  libavcodec/qsvenc.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/libavcodec/qsvenc.h b/libavcodec/qsvenc.h index
> > d48272224c..bb175c5df8 100644
> > --- a/libavcodec/qsvenc.h
> > +++ b/libavcodec/qsvenc.h
> > @@ -45,7 +45,7 @@
> >  #define QSV_HAVE_LA_DS  QSV_VERSION_ATLEAST(1, 8)  #define
> > QSV_HAVE_LA_HRD QSV_VERSION_ATLEAST(1, 11)
> >
> > -#if defined(_WIN32)
> > +#if defined(_WIN32) || defined(__CYGWIN__)
> >  #define QSV_HAVE_AVBR   QSV_VERSION_ATLEAST(1, 3)
> >  #define QSV_HAVE_ICQ    QSV_VERSION_ATLEAST(1, 8)
> >  #define QSV_HAVE_VCM    QSV_VERSION_ATLEAST(1, 8)
> >
> 
> Probably ok.
> 
> Does something actually go wrong here on Cygwin, or do you just end up
> without those features?  (This stuff should all be tested at runtime, but I
> can't ask you to rewrite it to do that...)
Agree that should be checked at runtime with MFXVideoENCODE_Query().
But unfortunately it just return yes or no (and messed with other input encoding parameters) instead of a list of supported features. Thus hard to handle in ffmpeg.
Do you have any detailed suggestion? Then maybe I can improve it

> 
> Are you going to want similar checks at the other instances of #if _WIN32 in
> that code?
> 
> Thanks,
> 
> - Mark