On Thu, Apr 4, 2019 at 8:54 PM Tomasz Figa <tfiga@xxxxxxxxxxxx> wrote: > > Hi, > > On Thu, Apr 4, 2019 at 9:26 PM Maxime Ripard <maxime.ripard@xxxxxxxxxxx> wrote: > > > > From: Pawel Osciak <posciak@xxxxxxxxxxxx> > > > > Stateless video codecs will require both the H264 metadata and slices in > > order to be able to decode frames. > > > > This introduces the definitions for a new pixel format for H264 slices that > > have been parsed, as well as the structures used to pass the metadata from > > the userspace to the kernel. > > > > Reviewed-by: Tomasz Figa <tfiga@xxxxxxxxxxxx> > > Signed-off-by: Pawel Osciak <posciak@xxxxxxxxxxxx> > > Signed-off-by: Guenter Roeck <groeck@xxxxxxxxxxxx> > > Co-developed-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx> > > Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx> > > --- > > Documentation/media/uapi/v4l/biblio.rst | 9 +- > > Documentation/media/uapi/v4l/ext-ctrls-codec.rst | 569 ++++++++++++++- > > Documentation/media/uapi/v4l/pixfmt-compressed.rst | 19 +- > > Documentation/media/uapi/v4l/vidioc-queryctrl.rst | 30 +- > > Documentation/media/videodev2.h.rst.exceptions | 5 +- > > drivers/media/v4l2-core/v4l2-ctrls.c | 42 +- > > drivers/media/v4l2-core/v4l2-ioctl.c | 1 +- > > include/media/h264-ctrls.h | 192 +++++- > > include/media/v4l2-ctrls.h | 13 +- > > include/uapi/linux/videodev2.h | 1 +- > > 10 files changed, 880 insertions(+), 1 deletion(-) > > create mode 100644 include/media/h264-ctrls.h > > > > diff --git a/Documentation/media/uapi/v4l/biblio.rst b/Documentation/media/uapi/v4l/biblio.rst > > index ec33768c055e..8f4eb8823d82 100644 > > --- a/Documentation/media/uapi/v4l/biblio.rst > > +++ b/Documentation/media/uapi/v4l/biblio.rst > > @@ -122,6 +122,15 @@ ITU BT.1119 > > > > :author: International Telecommunication Union (http://www.itu.ch) > > > > +.. _h264: > > + > > +ITU-T Rec. H.264 Specification (04/2017 Edition) > > +================================================ > > + > > +:title: ITU-T Recommendation H.264 "Advanced Video Coding for Generic Audiovisual Services" > > + > > +:author: International Telecommunication Union (http://www.itu.ch) > > + > > .. _jfif: > > > > JFIF > > diff --git a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst > > index 67a122339c0e..1285bfec7d3d 100644 > > --- a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst > > +++ b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst > > @@ -1371,6 +1371,575 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type - > > - Layer number > > > > > > +.. _v4l2-mpeg-h264: > > + > > +``V4L2_CID_MPEG_VIDEO_H264_SPS (struct)`` > > + Specifies the sequence parameter set (as extracted from the > > + bitstream) for the associated H264 slice data. This includes the > > + necessary parameters for configuring a stateless hardware decoding > > + pipeline for H264. The bitstream parameters are defined according > > + to :ref:`h264`, section 7.4.2.1.1 "Sequence Parameter Set Data > > + Semantics". For further documentation, refer to the above > > + specification, unless there is an explicit comment stating > > + otherwise. > > + > > + .. note:: > > + > > + This compound control is not yet part of the public kernel API and > > + it is expected to change. > > + > > +.. c:type:: v4l2_ctrl_h264_sps > > + > > +.. cssclass:: longtable > > + > > +.. flat-table:: struct v4l2_ctrl_h264_sps > > + :header-rows: 0 > > + :stub-columns: 0 > > + :widths: 1 1 2 > > + > > + * - __u8 > > + - ``profile_idc`` > > + - > > + * - __u8 > > + - ``constraint_set_flags`` > > + - See :ref:`Sequence Parameter Set Constraints Set Flags <h264_sps_constraints_set_flags>` > > + * - __u8 > > + - ``level_idc`` > > + - > > + * - __u8 > > + - ``seq_parameter_set_id`` > > + - > > + * - __u8 > > + - ``chroma_format_idc`` > > + - > > + * - __u8 > > + - ``bit_depth_luma_minus8`` > > + - > > + * - __u8 > > + - ``bit_depth_chroma_minus8`` > > + - > > + * - __u8 > > + - ``log2_max_frame_num_minus4`` > > + - > > + * - __u8 > > + - ``pic_order_cnt_type`` > > + - > > + * - __u8 > > + - ``log2_max_pic_order_cnt_lsb_minus4`` > > + - > > + * - __u8 > > + - ``max_num_ref_frames`` > > + - > > + * - __u8 > > + - ``num_ref_frames_in_pic_order_cnt_cycle`` > > + - > > + * - __s32 > > + - ``offset_for_ref_frame[255]`` > > + - > > + * - __s32 > > + - ``offset_for_non_ref_pic`` > > + - > > + * - __s32 > > + - ``offset_for_top_to_bottom_field`` > > + - > > + * - __u16 > > + - ``pic_width_in_mbs_minus1`` > > + - > > + * - __u16 > > + - ``pic_height_in_map_units_minus1`` > > + - > > We recently had some reflection with Alex that this is redundant with > the width and height in the OUTPUT format. It may also apply to some > other fields in these structs. I feel like they should be removed and > passed via corresponding generic V4L2 properties - format, selection, > etc. > > The same problem is also present in the MPEG2 controls. In fact, there > was a patch already which used some fields from the controls to > calculate the destination buffer strides, rather than bytesperline in > the format. > > Since we're in staging, it could be done with a follow-up patch, though. Just my two cents. I played with some codecs a while back. IIRC some specify a "codec" size in addition to the actual picture size, like when the encoder does padding to fit the requirements of the codec (spec). Is this needed anywhere? ChenYu
