Re: [PATCH v2 1/2] media: v4l2-ctrl: Add control for VP9 profile

[Tomasz Figa]

On Fri, Jun 8, 2018 at 6:40 PM Hans Verkuil <hverkuil@xxxxxxxxx> wrote:
>
> On 06/08/2018 11:31 AM, Tomasz Figa wrote:
> > Hi Hans,
> >
> > On Fri, Jun 8, 2018 at 6:29 PM Hans Verkuil <hverkuil@xxxxxxxxx> wrote:
> >>
> >> On 05/30/2018 09:16 AM, Keiichi Watanabe wrote:
> >>> Add a new control V4L2_CID_MPEG_VIDEO_VP9_PROFILE for selecting desired
> >>> profile for VP9 encoder and querying for supported profiles by VP9 encoder
> >>> or decoder.
> >>>
> >>> An existing control V4L2_CID_MPEG_VIDEO_VPX_PROFILE cannot be
> >>> used for querying since it is not a menu control but an integer
> >>> control, which cannot return an arbitrary set of supported profiles.
> >>>
> >>> The new control V4L2_CID_MPEG_VIDEO_VP9_PROFILE is a menu control as
> >>> with controls for other codec profiles. (e.g. H264)
> >>
> >> Please ignore my reply to patch 2/2. I looked at this a bit more and what you
> >> should do is to change the type of V4L2_CID_MPEG_VIDEO_VPX_PROFILE to enum.
> >
> > Note that we still need a way to query VP8 and VP9 separately, since
> > the supported profiles will differ. (Most of hardware we have today
> > support all 4 profiles of VP8 and only profile 0 of VP9.)
>
> Urgh. So V4L2_CID_MPEG_VIDEO_VPX_PROFILE is really just for VP8?

I don't know the background, but it's completely inconsistent to
similar controls we have for other codecs. (Also we don't have
V4L2_CID_MPEG_VIDEO_PROFILE, but rather 1 control for each codec).

>
> In that case I would suggest that we rename V4L2_CID_MPEG_VIDEO_VPX_PROFILE to
> V4L2_CID_MPEG_VIDEO_VP8_PROFILE and change it to an enum. Also add this line
> to v4l2-controls.h:
>
> #define V4L2_CID_MPEG_VIDEO_VPX_PROFILE V4L2_CID_MPEG_VIDEO_VP8_PROFILE
>
> And add a new V4L2_CID_MPEG_VIDEO_VP9_PROFILE (basically this patch).
>
> Would that work?
>
> This standardizes on enums for all profile controls (except s5p-mfc, which
> makes its own int control, up to samsung to decide whether or not to change
> that), and you have VP8 and VP9 specific profiles.

Sounds good to me, thanks.

Best regards,
Tomasz

>
> Regards,
>
>         Hans
>
> >
> > Best regards,
> > Tomasz
> >
> >>
> >> All other codec profile controls are all enums, so the fact that VPX_PROFILE
> >> isn't is a bug. Changing the type should not cause any problems since the same
> >> control value is used when you set the control.
> >>
> >> Sylwester: I see that s5p-mfc uses this control, but it is explicitly added
> >> as an integer type control, so the s5p-mfc driver should not be affected by
> >> changing the type of this control.
> >>
> >> Stanimir: this will slightly change the venus driver, but since it is a very
> >> recent driver I think we can get away with changing the core type of the
> >> VPX_PROFILE control. I think that's better than ending up with two controls
> >> that do the same thing.
> >>
> >> Regards,
> >>
> >>         Hans
> >>
> >>>
> >>> Signed-off-by: Keiichi Watanabe <keiichiw@xxxxxxxxxxxx>
> >>> ---
> >>>  .../media/uapi/v4l/extended-controls.rst      | 26 +++++++++++++++++++
> >>>  drivers/media/v4l2-core/v4l2-ctrls.c          | 12 +++++++++
> >>>  include/uapi/linux/v4l2-controls.h            |  8 ++++++
> >>>  3 files changed, 46 insertions(+)
> >>>
> >>> diff --git a/Documentation/media/uapi/v4l/extended-controls.rst b/Documentation/media/uapi/v4l/extended-controls.rst
> >>> index 03931f9b1285..4f7f128a4998 100644
> >>> --- a/Documentation/media/uapi/v4l/extended-controls.rst
> >>> +++ b/Documentation/media/uapi/v4l/extended-controls.rst
> >>> @@ -1959,6 +1959,32 @@ enum v4l2_vp8_golden_frame_sel -
> >>>      Select the desired profile for VPx encoder. Acceptable values are 0,
> >>>      1, 2 and 3 corresponding to encoder profiles 0, 1, 2 and 3.
> >>>
> >>> +.. _v4l2-mpeg-video-vp9-profile:
> >>> +
> >>> +``V4L2_CID_MPEG_VIDEO_VP9_PROFILE``
> >>> +    (enum)
> >>> +
> >>> +enum v4l2_mpeg_video_vp9_profile -
> >>> +    This control allows to select the profile for VP9 encoder.
> >>> +    This is also used to enumerate supported profiles by VP9 encoder or decoder.
> >>> +    Possible values are:
> >>> +
> >>> +
> >>> +
> >>> +.. flat-table::
> >>> +    :header-rows:  0
> >>> +    :stub-columns: 0
> >>> +
> >>> +    * - ``V4L2_MPEG_VIDEO_VP9_PROFILE_0``
> >>> +      - Profile 0
> >>> +    * - ``V4L2_MPEG_VIDEO_VP9_PROFILE_1``
> >>> +      - Profile 1
> >>> +    * - ``V4L2_MPEG_VIDEO_VP9_PROFILE_2``
> >>> +      - Profile 2
> >>> +    * - ``V4L2_MPEG_VIDEO_VP9_PROFILE_3``
> >>> +      - Profile 3
> >>> +
> >>> +
> >>>
> >>>  High Efficiency Video Coding (HEVC/H.265) Control Reference
> >>>  -----------------------------------------------------------
> >>> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
> >>> index d29e45516eb7..401ce21c2e63 100644
> >>> --- a/drivers/media/v4l2-core/v4l2-ctrls.c
> >>> +++ b/drivers/media/v4l2-core/v4l2-ctrls.c
> >>> @@ -431,6 +431,13 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
> >>>               "Use Previous Specific Frame",
> >>>               NULL,
> >>>       };
> >>> +     static const char * const vp9_profile[] = {
> >>> +             "0",
> >>> +             "1",
> >>> +             "2",
> >>> +             "3",
> >>> +             NULL,
> >>> +     };
> >>>
> >>>       static const char * const flash_led_mode[] = {
> >>>               "Off",
> >>> @@ -614,6 +621,8 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
> >>>               return mpeg4_profile;
> >>>       case V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL:
> >>>               return vpx_golden_frame_sel;
> >>> +     case V4L2_CID_MPEG_VIDEO_VP9_PROFILE:
> >>> +             return vp9_profile;
> >>>       case V4L2_CID_JPEG_CHROMA_SUBSAMPLING:
> >>>               return jpeg_chroma_subsampling;
> >>>       case V4L2_CID_DV_TX_MODE:
> >>> @@ -841,6 +850,8 @@ const char *v4l2_ctrl_get_name(u32 id)
> >>>       case V4L2_CID_MPEG_VIDEO_VPX_P_FRAME_QP:                return "VPX P-Frame QP Value";
> >>>       case V4L2_CID_MPEG_VIDEO_VPX_PROFILE:                   return "VPX Profile";
> >>>
> >>> +     case V4L2_CID_MPEG_VIDEO_VP9_PROFILE:                   return "VP9 Profile";
> >>> +
> >>>       /* HEVC controls */
> >>>       case V4L2_CID_MPEG_VIDEO_HEVC_I_FRAME_QP:               return "HEVC I-Frame QP Value";
> >>>       case V4L2_CID_MPEG_VIDEO_HEVC_P_FRAME_QP:               return "HEVC P-Frame QP Value";
> >>> @@ -1180,6 +1191,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
> >>>       case V4L2_CID_DEINTERLACING_MODE:
> >>>       case V4L2_CID_TUNE_DEEMPHASIS:
> >>>       case V4L2_CID_MPEG_VIDEO_VPX_GOLDEN_FRAME_SEL:
> >>> +     case V4L2_CID_MPEG_VIDEO_VP9_PROFILE:
> >>>       case V4L2_CID_DETECT_MD_MODE:
> >>>       case V4L2_CID_MPEG_VIDEO_HEVC_PROFILE:
> >>>       case V4L2_CID_MPEG_VIDEO_HEVC_LEVEL:
> >>> diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> >>> index 8d473c979b61..56203b7b715c 100644
> >>> --- a/include/uapi/linux/v4l2-controls.h
> >>> +++ b/include/uapi/linux/v4l2-controls.h
> >>> @@ -589,6 +589,14 @@ enum v4l2_vp8_golden_frame_sel {
> >>>  #define V4L2_CID_MPEG_VIDEO_VPX_P_FRAME_QP           (V4L2_CID_MPEG_BASE+510)
> >>>  #define V4L2_CID_MPEG_VIDEO_VPX_PROFILE                      (V4L2_CID_MPEG_BASE+511)
> >>>
> >>> +#define V4L2_CID_MPEG_VIDEO_VP9_PROFILE                      (V4L2_CID_MPEG_BASE+512)
> >>> +enum v4l2_mpeg_video_vp9_profile {
> >>> +     V4L2_MPEG_VIDEO_VP9_PROFILE_0                           = 0,
> >>> +     V4L2_MPEG_VIDEO_VP9_PROFILE_1                           = 1,
> >>> +     V4L2_MPEG_VIDEO_VP9_PROFILE_2                           = 2,
> >>> +     V4L2_MPEG_VIDEO_VP9_PROFILE_3                           = 3,
> >>> +};
> >>> +
> >>>  /* CIDs for HEVC encoding. */
> >>>
> >>>  #define V4L2_CID_MPEG_VIDEO_HEVC_MIN_QP              (V4L2_CID_MPEG_BASE + 600)
> >>> --
> >>> 2.17.0.921.gf22659ad46-goog
> >>>
> >>
>