Re: [PATCH v6] [media] v4l: add I / P frame min max QP definitions
From: Fish Lin
Date: Thu Mar 28 2019 - 22:58:12 EST
Hans Verkuil <hverkuil-cisco@xxxxxxxxx> æ 2019å3æ28æ éå äå11:01åéï
>
> On 3/21/19 3:20 AM, Fish Lin wrote:
> > 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
> >
> > 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 v5:
> > - Adjust documentation wording.
> >
> > Changelog since v4:
> > - Fix patch subject and send again.
> >
> > 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..5b2db52d3b4e 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 the H264 I frame to limit I frame
> > + quality to 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_I_FRAME_MAX_QP (integer)``
> > + Maximum quantization parameter for the H264 I frame to limit I frame
> > + quality to 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 the H264 P frame to limit P frame
> > + quality to 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 the H264 P frame to limit P frame
> > + quality to 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)
>
> There is no need for a gap in numbering. Just start with +385.
>
> Sorry for this, I missed that in the previous reviews. Everything else looks good
> to me, so if you post a v7 I'll take it.
>
> Thanks!
>
> Hans
>
> > +#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)
> > --
> > 2.21.0.225.g810b269d1ac-goog
> >
>
Thanks for the review!
Fish