[FFmpeg-devel] [EXT] [PATCH v5] avcodec/v4l2_m2m_enc: Support changing qmin/qmax

Andriy Gelman andriy.gelman at gmail.com
Thu Apr 30 19:00:54 EEST 2020


On Wed, 29. Apr 02:45, Ming Qian wrote:
> > -----Original Message-----
> > From: ffmpeg-devel <ffmpeg-devel-bounces at ffmpeg.org> On Behalf Of Andriy
> > Gelman
> > Sent: Wednesday, April 29, 2020 1:07 AM
> > To: ffmpeg-devel at ffmpeg.org
> > Cc: Andriy Gelman <andriy.gelman at gmail.com>
> > Subject: [EXT] [FFmpeg-devel] [PATCH v5] avcodec/v4l2_m2m_enc: Support
> > changing qmin/qmax
> > 
> > Caution: EXT Email
> > 
> > From: Andriy Gelman <andriy.gelman at gmail.com>
> > 
> > Hard coded parameters for qmin and qmax are currently used to initialize
> > v4l2_m2m device. This commit uses values from avctx->{qmin,qmax} if they
> > are set.
> > 
> > Signed-off-by: Andriy Gelman <andriy.gelman at gmail.com>
> > ---
> > 
> >  Changes in v5:
> >     - Check that qmin does not exceed qmax (thanks for feedback from Ming
> > Qian)
> > 
> >  libavcodec/v4l2_m2m_enc.c | 23 +++++++++++++++++++----
> >  1 file changed, 19 insertions(+), 4 deletions(-)
> > 
> > diff --git a/libavcodec/v4l2_m2m_enc.c b/libavcodec/v4l2_m2m_enc.c index
> > 8454e2326c..b22cfc61fb 100644
> > --- a/libavcodec/v4l2_m2m_enc.c
> > +++ b/libavcodec/v4l2_m2m_enc.c
> > @@ -31,6 +31,7 @@
> >  #include "v4l2_context.h"
> >  #include "v4l2_m2m.h"
> >  #include "v4l2_fmt.h"
> > +#include "internal.h"
> > 
> >  #define MPEG_CID(x) V4L2_CID_MPEG_VIDEO_##x  #define MPEG_VIDEO(x)
> > V4L2_MPEG_VIDEO_##x @@ -252,11 +253,18 @@ static int
> > v4l2_prepare_encoder(V4L2m2mContext *s)
> >          return 0;
> >      }
> > 
> > -    if (qmin != avctx->qmin || qmax != avctx->qmax)
> > -        av_log(avctx, AV_LOG_WARNING, "Encoder adjusted: qmin (%d),
> > qmax (%d)\n", qmin, qmax);
> > +    if (avctx->qmin >= 0 && avctx->qmax >= 0 && avctx->qmin > avctx->qmax)
> > {
> > +        av_log(avctx, AV_LOG_WARNING, "Invalid qmin:%d qmax:%d. qmin
> > should not "
> > +                                      "exceed qmax\n", avctx->qmin,
> > avctx->qmax);
> > +    } else {
> > +        qmin = avctx->qmin >= 0 ? avctx->qmin : qmin;
> > +        qmax = avctx->qmax >= 0 ? avctx->qmax : qmax;
> > +    }
> > 
> > -    v4l2_set_ext_ctrl(s, qmin_cid, qmin, "minimum video quantizer scale", 0);
> > -    v4l2_set_ext_ctrl(s, qmax_cid, qmax, "maximum video quantizer scale",
> > 0);
> > +    v4l2_set_ext_ctrl(s, qmin_cid, qmin, "minimum video quantizer scale",
> > +                      avctx->qmin >= 0);
> > +    v4l2_set_ext_ctrl(s, qmax_cid, qmax, "maximum video quantizer scale",
> > +                      avctx->qmax >= 0);
> > 
> >      return 0;
> >  }
> > @@ -369,6 +377,12 @@ static const AVOption options[] = {
> >      { NULL },
> >  };
> > 
> > +static const AVCodecDefault v4l2_m2m_defaults[] = {
> > +    { "qmin", "-1" },
> > +    { "qmax", "-1" },
> > +    { NULL },
> > +};
> > +
> >  #define M2MENC_CLASS(NAME) \
> >      static const AVClass v4l2_m2m_ ## NAME ## _enc_class = { \
> >          .class_name = #NAME "_v4l2m2m_encoder", \ @@ -390,6 +404,7
> > @@ static const AVOption options[] = {
> >          .send_frame     = v4l2_send_frame, \
> >          .receive_packet = v4l2_receive_packet, \
> >          .close          = v4l2_encode_close, \
> > +        .defaults       = v4l2_m2m_defaults, \
> >          .capabilities   = AV_CODEC_CAP_HARDWARE |
> > AV_CODEC_CAP_DELAY, \
> >          .wrapper_name   = "v4l2m2m", \
> >      };
> > --
> > 2.25.1
> > 

> 
> Lgtm
> 

Thanks, I also locally put internal.h header in the correct alphabetical order.

Will apply Sunday if no one objects. 

-- 
Andriy


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