Re: [PATCH v4] Add following V4L2 QP parameters for H.264: * V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MIN_QP * V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MAX_QP * V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MIN_QP * V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MAX_QP

[Fish Lin]

Got it, thanks!

Fish

Hans Verkuil <hverkuil-cisco@xxxxxxxxx> æ 2019å3æ20æ éä äå11:00åéï
>
> This subject line is insanely long :-)
>
> Please use a short subject line for v5 (i.e. "Add V4L2 QP parameters for H.264")
> and mention the actual parameters you are adding in the commit log.
>
> Some more comments below:
>
> On 3/15/19 9:40 AM, Fish Lin wrote:
> > These controls will limit QP range for intra and inter frame,
> > provide more manual control to improve video encode quality.
> >
> > Signed-off-by: Fish Lin <linfish@xxxxxxxxxx>
> > ---
> > Changelog since v3:
> > - Put document in ext-ctrls-codec.rst instead of extended-controls.rst
> >   (which was previous version).
> >
> > Changelog since v2:
> > - Add interaction with V4L2_CID_MPEG_VIDEO_H264_MIN/MAX_QP
> >   description in the document.
> >
> > Changelog since v1:
> > - Add description in document.
> >
> >  .../media/uapi/v4l/ext-ctrls-codec.rst        | 24 +++++++++++++++++++
> >  drivers/media/v4l2-core/v4l2-ctrls.c          |  4 ++++
> >  include/uapi/linux/v4l2-controls.h            |  6 +++++
> >  3 files changed, 34 insertions(+)
> >
> > diff --git a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst
> > index c97fb7923be5..de60b2e788eb 100644
> > --- a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst
> > +++ b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst
> > @@ -1048,6 +1048,30 @@ enum v4l2_mpeg_video_h264_entropy_mode -
> >      Quantization parameter for an B frame for H264. Valid range: from 0
> >      to 51.
> >
> > +``V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MIN_QP (integer)``
> > +    Minimum quantization parameter for H264 I frame, to limit I frame
>
> H264 -> the H264
> frame, to -> frame to
>
> Same below.
>
> > +    quality in a range. Valid range: from 0 to 51. If
>
> in -> to
>
> (you limit a value *to* a range, not 'in a range')
>
> Same below.
>
> Regards,
>
>         Hans
>
> > +    V4L2_CID_MPEG_VIDEO_H264_MIN_QP is also set, the quantization parameter
> > +    should be chosen to meet both requirements.
> > +
> > +``V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MAX_QP (integer)``
> > +    Maximum quantization parameter for H264 I frame, to limit I frame
> > +    quality in a range. Valid range: from 0 to 51. If
> > +    V4L2_CID_MPEG_VIDEO_H264_MAX_QP is also set, the quantization parameter
> > +    should be chosen to meet both requirements.
> > +
> > +``V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MIN_QP (integer)``
> > +    Minimum quantization parameter for H264 P frame, to limit P frame
> > +    quality in a range. Valid range: from 0 to 51. If
> > +    V4L2_CID_MPEG_VIDEO_H264_MIN_QP is also set, the quantization parameter
> > +    should be chosen to meet both requirements.
> > +
> > +``V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MAX_QP (integer)``
> > +    Maximum quantization parameter for H264 P frame, to limit P frame
> > +    quality in a range. Valid range: from 0 to 51. If
> > +    V4L2_CID_MPEG_VIDEO_H264_MAX_QP is also set, the quantization parameter
> > +    should be chosen to meet both requirements.
> > +
> >  ``V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP (integer)``
> >      Quantization parameter for an I frame for MPEG4. Valid range: from 1
> >      to 31.
> > diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
> > index b79d3bbd8350..115fb8debe23 100644
> > --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> > +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> > @@ -828,6 +828,10 @@ const char *v4l2_ctrl_get_name(u32 id)
> >       case V4L2_CID_MPEG_VIDEO_H264_CONSTRAINED_INTRA_PREDICTION:
> >                                                               return "H264 Constrained Intra Pred";
> >       case V4L2_CID_MPEG_VIDEO_H264_CHROMA_QP_INDEX_OFFSET:   return "H264 Chroma QP Index Offset";
> > +     case V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MIN_QP:           return "H264 I-Frame Minimum QP Value";
> > +     case V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MAX_QP:           return "H264 I-Frame Maximum QP Value";
> > +     case V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MIN_QP:           return "H264 P-Frame Minimum QP Value";
> > +     case V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MAX_QP:           return "H264 P-Frame Maximum QP Value";
> >       case V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP:              return "MPEG4 I-Frame QP Value";
> >       case V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP:              return "MPEG4 P-Frame QP Value";
> >       case V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP:              return "MPEG4 B-Frame QP Value";
> > diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> > index 06479f2fb3ae..4421baa84177 100644
> > --- a/include/uapi/linux/v4l2-controls.h
> > +++ b/include/uapi/linux/v4l2-controls.h
> > @@ -535,6 +535,12 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type {
> >  #define V4L2_CID_MPEG_VIDEO_H264_HIERARCHICAL_CODING_LAYER_QP        (V4L2_CID_MPEG_BASE+382)
> >  #define V4L2_CID_MPEG_VIDEO_H264_CONSTRAINED_INTRA_PREDICTION        (V4L2_CID_MPEG_BASE+383)
> >  #define V4L2_CID_MPEG_VIDEO_H264_CHROMA_QP_INDEX_OFFSET              (V4L2_CID_MPEG_BASE+384)
> > +
> > +#define V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MIN_QP      (V4L2_CID_MPEG_BASE+390)
> > +#define V4L2_CID_MPEG_VIDEO_H264_I_FRAME_MAX_QP      (V4L2_CID_MPEG_BASE+391)
> > +#define V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MIN_QP      (V4L2_CID_MPEG_BASE+392)
> > +#define V4L2_CID_MPEG_VIDEO_H264_P_FRAME_MAX_QP      (V4L2_CID_MPEG_BASE+393)
> > +
> >  #define V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP (V4L2_CID_MPEG_BASE+400)
> >  #define V4L2_CID_MPEG_VIDEO_MPEG4_P_FRAME_QP (V4L2_CID_MPEG_BASE+401)
> >  #define V4L2_CID_MPEG_VIDEO_MPEG4_B_FRAME_QP (V4L2_CID_MPEG_BASE+402)
> >
>