| Message ID | 20210222122406.41782-1-benjamin.gaignard@collabora.com |
|---|---|
| Headers | show |
| Series | Add HANTRO G2/HEVC decoder support for IMX8MQ | expand |
Hi Benjamin, On Mon, 2021-02-22 at 13:23 +0100, Benjamin Gaignard wrote: > The IMX8MQ got two VPUs but until now only G1 has been enabled. > This series aim to add the second VPU (aka G2) and provide basic > HEVC decoding support. > > To be able to decode HEVC it is needed to add/update some of the > structures in the uapi. In addition of them one HANTRO dedicated > control is required to inform the driver of the numbre of bits to skip > at the beginning of the slice header. > The hardware require to allocate few auxiliary buffers to store the > references frame or tile size data. > > The driver has been tested with fluster test suite stream. > For example with this command: ./fluster.py run -ts JCT-VC-HEVC_V1 -d GStreamer-H.265-V4L2SL-Gst1.0 > > This series depends of the reset rework posted here: https://www.spinics.net/lists/arm-kernel/msg875766.html > > Finally the both VPUs will have a node the device-tree and be > independent from v4l2 point of view. > > A branch with all the dev is available here: > https://gitlab.collabora.com/benjamin.gaignard/for-upstream/-/commits/upstream_g2_v2 > > version 3: > - Fix typo in Hantro v4l2 dedicated control > - Add documentation for the new structures and fields > - Rebased on top of media_tree for-linus-5.12-rc1 tag > > version 2: > - remove all change related to scaling > - squash commits to a coherent split > - be more verbose about the added fields > - fix the comments done by Ezequiel about dma_alloc_coherent usage > - fix Dan's comments about control copy, reverse the test logic > in tile_buffer_reallocate, rework some goto and return cases. > - be more verbose about why I change the bindings > - remove all sign-off expect mime since it is confusing I don't think it's about having less confusing commits, but trying to describe fairly accurately the origin of the work and the authorship of changes. In this series I believe we have three cases, please correct me if I'm wrong: * Changes that you have authored, for instance it would seem to me that "dt-bindings: media: nxp,imx8mq-vpu: Update bindings", and "media: uapi: Add a control for HANTRO driver" would be in that category. * Changes that Adrian and/or me have initially authored, where both Adrian and me did further work, and also where you did significant work on as well. IOW, changes where the three of us did significant work. I guess in this case, the original author could be the author of the patch (git's Author tag), and additionally authorship would be indicated with Co-developed-by tags. commit 494adacd844e5656b570895a82bc343438b23023 Author: Adrian Ratiu <adrian.ratiu@collabora.com> Date: Thu Feb 18 12:17:37 2021 +0100 media: hantro: Introduce G2/HEVC decoder ... Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Co-developed-by: Ezequiel Garcia <ezequiel@collabora.com> Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com> Co-developed-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> * And finally changes with an original author (Adrian or me), which you haven't changed, but you are just submitting (or you did minor work). Maybe with the current way of splitting commits we don't have these type of patches, but just for the sake of it, let's say there's a commit authored by Adrian that you are mostly picking up, it would be: commit 896776d3bcd032808e4d5772e6749da5dd4eec42 Author: Adrian Ratiu <adrian.ratiu@collabora.com> Date: Fri Feb 5 12:14:16 2021 +0100 media: hantro: Some change ... Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> Thanks a lot! Ezequiel > - remove useless clocks in VPUs nodes > > Benjamin > > Benjamin Gaignard (9): > media: hevc: Modify structures to follow H265 ITU spec > media: hantro: Define HEVC codec profiles and supported features > media: hantro: Add a field to distinguish the hardware versions > media: uapi: Add a control for HANTRO driver > media: hantro: Introduce G2/HEVC decoder > media: hantro: handle V4L2_PIX_FMT_HEVC_SLICE control > media: hantro: IMX8M: add variant for G2/HEVC codec > dt-bindings: media: nxp,imx8mq-vpu: Update bindings > arm64: dts: imx8mq: Add node to G2 hardware > > .../bindings/media/nxp,imx8mq-vpu.yaml | 54 +- > .../media/v4l/ext-ctrls-codec.rst | 126 +++- > .../media/v4l/vidioc-queryctrl.rst | 6 + > arch/arm64/boot/dts/freescale/imx8mq.dtsi | 41 +- > drivers/media/v4l2-core/v4l2-ctrls.c | 26 +- > drivers/staging/media/hantro/Makefile | 2 + > drivers/staging/media/hantro/hantro.h | 34 +- > drivers/staging/media/hantro/hantro_drv.c | 103 +++ > .../staging/media/hantro/hantro_g2_hevc_dec.c | 587 ++++++++++++++++++ > drivers/staging/media/hantro/hantro_g2_regs.h | 198 ++++++ > drivers/staging/media/hantro/hantro_hevc.c | 321 ++++++++++ > drivers/staging/media/hantro/hantro_hw.h | 48 ++ > .../staging/media/hantro/hantro_postproc.c | 17 + > drivers/staging/media/hantro/hantro_v4l2.c | 1 + > drivers/staging/media/hantro/imx8m_vpu_hw.c | 95 ++- > drivers/staging/media/sunxi/cedrus/cedrus.c | 6 + > drivers/staging/media/sunxi/cedrus/cedrus.h | 1 + > .../staging/media/sunxi/cedrus/cedrus_dec.c | 2 + > .../staging/media/sunxi/cedrus/cedrus_h265.c | 6 +- > include/media/hevc-ctrls.h | 45 +- > include/uapi/linux/hantro-v4l2-controls.h | 20 + > include/uapi/linux/v4l2-controls.h | 5 + > 22 files changed, 1674 insertions(+), 70 deletions(-) > create mode 100644 drivers/staging/media/hantro/hantro_g2_hevc_dec.c > create mode 100644 drivers/staging/media/hantro/hantro_g2_regs.h > create mode 100644 drivers/staging/media/hantro/hantro_hevc.c > create mode 100644 include/uapi/linux/hantro-v4l2-controls.h >
Dne četrtek, 25. februar 2021 ob 18:34:48 CET je Ezequiel Garcia napisal(a): > Hey Jernej, > > On Thu, 2021-02-25 at 18:01 +0100, Jernej Škrabec wrote: > > Hi Ezequiel, > > > > Dne četrtek, 25. februar 2021 ob 14:09:52 CET je Ezequiel Garcia napisal(a): > > > Hi Benjamin, > > > > > > Thanks for the good work. > > > > > > On Mon, 2021-02-22 at 13:23 +0100, Benjamin Gaignard wrote: > > > > The H.265 ITU specification (section 7.4) define the general > > > > slice segment header semantics. > > > > Modified/added fields are: > > > > - video_parameter_set_id: (7.4.3.1) identifies the VPS for > > > > reference by other syntax elements. > > > > - seq_parameter_set_id: (7.4.3.2.1) specifies the value of > > > > the vps_video_parameter_set_id of the active VPS. > > > > - chroma_format_idc: (7.4.3.2.1) specifies the chroma sampling > > > > relative to the luma sampling > > > > - pic_parameter_set_id: (7.4.3.3.1) identifies the PPS for > > > > reference by other syntax elements > > > > - num_ref_idx_l0_default_active_minus1: (7.4.3.3.1) specifies > > > > the inferred value of num_ref_idx_l0_active_minus1 > > > > - num_ref_idx_l1_default_active_minus1: (7.4.3.3.1) specifies > > > > the inferred value of num_ref_idx_l1_active_minus1 > > > > - slice_segment_addr: (7.4.7.1) specifies the address of > > > > the first coding tree block in the slice segment > > > > - num_entry_point_offsets: (7.4.7.1) specifies the number of > > > > entry_point_offset_minus1[ i ] syntax elements in the slice header > > > > > > > > Add HEVC decode params contains the information used in section > > > > "8.3 Slice decoding process" of the specification to let the hardware > > > > perform decoding of a slices. > > > > > > > > Adapt Cedrus driver according to these changes. > > > > > > > > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> > > > > --- > > > > version 3: > > > > - Add documentation about the new structuers and fields. > > > > > > > > version 2: > > > > - remove all change related to scaling > > > > - squash commits to a coherent split > > > > - be more verbose about the added fields > > > > > > > > .../media/v4l/ext-ctrls-codec.rst | 126 ++++++++++++++ +--- > > > > .../media/v4l/vidioc-queryctrl.rst | 6 + > > > > drivers/media/v4l2-core/v4l2-ctrls.c | 26 +++- > > > > drivers/staging/media/sunxi/cedrus/cedrus.c | 6 + > > > > drivers/staging/media/sunxi/cedrus/cedrus.h | 1 + > > > > .../staging/media/sunxi/cedrus/cedrus_dec.c | 2 + > > > > .../staging/media/sunxi/cedrus/cedrus_h265.c | 6 +- > > > > include/media/hevc-ctrls.h | 45 +++++-- > > > > 8 files changed, 186 insertions(+), 32 deletions(-) > > > > > > > > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/ > > Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > > > index 00944e97d638..5e6d77e858c0 100644 > > > > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > > > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > > > @@ -3109,6 +3109,15 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > > > :stub-columns: 0 > > > > :widths: 1 1 2 > > > > > > > > + * - __u8 > > > > + - ``video_parameter_set_id`` > > > > + - Identifies the VPS for reference by other syntax elements > > > > + * - __u8 > > > > + - ``seq_parameter_set_id̀`` > > > > + - Specifies the value of the vps_video_parameter_set_id of the > > active VPS > > > > + * - __u8 > > > > + - ``chroma_format_idc`` > > > > + - Specifies the chroma sampling relative to the luma sampling > > > > > > None of these fields seem needed for the Hantro G2 driver, > > > so I suggest you drop them for now. > > > > > > > * - __u16 > > > > - ``pic_width_in_luma_samples`` > > > > - > > > > @@ -3172,6 +3181,9 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > > > * - __u8 > > > > - ``chroma_format_idc`` > > > > - > > > > + * - __u8 > > > > + - ``num_slices`` > > > > + > > > > > > Not used, but also doesn't seem part of the SPS syntax. If we have to > > > pass the number of slices, we'll need another mechanism. > > > > > > > - > > > > * - __u64 > > > > - ``flags`` > > > > - See :ref:`Sequence Parameter Set Flags <hevc_sps_flags>` > > > > @@ -3231,9 +3243,18 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > > > :stub-columns: 0 > > > > :widths: 1 1 2 > > > > > > > > + * - __u8 > > > > + - ``pic_parameter_set_id`` > > > > + - Identifies the PPS for reference by other syntax elements > > > > > > Not used. > > > > > > > * - __u8 > > > > - ``num_extra_slice_header_bits`` > > > > - > > > > + * - __u8 > > > > + - ``num_ref_idx_l0_default_active_minus1`` > > > > + - Specifies the inferred value of num_ref_idx_l0_active_minus1 > > > > + * - __u8 > > > > + - ``num_ref_idx_l1_default_active_minus1`` > > > > + - Specifies the inferred value of num_ref_idx_l1_active_minus1 > > > > * - __s8 > > > > - ``init_qp_minus26`` > > > > - > > > > @@ -3342,6 +3363,12 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > > > * - ``V4L2_HEVC_PPS_FLAG_SLICE_SEGMENT_HEADER_EXTENSION_PRESENT`` > > > > - 0x00040000 > > > > - > > > > + * - ``V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT`` > > > > + - 0x00080000 > > > > + - > > > > + * - ``V4L2_HEVC_PPS_FLAG_UNIFORM_SPACING`` > > > > + - 0x00100000 > > > > + - > > > > > > > > > > I suggest to do all the PPS control changes in a separate patch, > > > feels easier to review and cleaner as you can explain the > > > changes with more detail in the commit description. > > > > > > Looking at the PPS syntax for tiles, I'm wondering if these > > > deserve their own control, which would be used if tiles are enabled, > > > i.e. V4L2_HEVC_PPS_FLAG_TILES_ENABLED is set. > > > > > > __u8 num_tile_columns_minus1; > > > __u8 num_tile_rows_minus1; > > > __u8 column_width_minus1[20]; > > > __u8 row_height_minus1[22]; > > > > > > Not something we necessarily have to tackle now. > > > > > > > ``V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS (struct)`` > > > > Specifies various slice-specific parameters, especially from the NAL > > unit > > > > @@ -3366,6 +3393,12 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > > > * - __u32 > > > > - ``data_bit_offset`` > > > > - Offset (in bits) to the video data in the current slice data. > > > > + * - __u32 > > > > + - ``slice_segment_addr`` > > > > + - Specifies the address of the first coding tree block in the slice > > segment > > > > > > Not used. > > > > > > > + * - __u32 > > > > + - ``num_entry_point_offsets`` > > > > + - Specifies the number of entry_point_offset_minus1[ i ] syntax > > elements in the slice header > > > > > > Not used. > > > > While above two fields may not be used in Hantro, they are for sure useful for > > Cedrus and RPi4. I would like to keep them, otherwise with such approach HEVC > > will stay in staging for a long time. I'm still baffled why scaling matrix > > control was dropped. It would fit well in Cedrus and RPi4 driver and after a > > quick look, it seems that it was used in driver in later patch. > > > > I'd like to make sure each modification we are making to the uAPI > goes in the right direction, that is in the direction of moving > the API out of staging. > > Since reviewing each field is quite hard, and opens some discussions, > I wanted to keep this patchset specific to what's needed for Hantro G2. > > The Scaling matrix control is certainly a good one, as well as the ones > needed for Cedrus and RPi4. However, I feel it's better to discuss > them in their own "uAPI review" series so we can review all the changes > with an API hat. > > This way we decouple the Hantro G2 discussion and work from the API work. > > Also please feel free to submit RFC patches fo Cedrus and RPi4 > (API and driver changes). We can certainly start the discussion around that, > with driver changes in context. I don't know much about RPi4 driver, only few implementation details, so you'll have to ping developer who wrote it. Regarding HEVC on Cedrus - it has one pain point - it needs entry point table which in turn needs support for variable arrays in order to be feasable AFAIK. I don't plan to develop that. Patches for scaling matrix and segment address were sent a bit more than a year ago but were turned down because they change control structures (among other things). Sorry to say, but I work on other things now, so Cedrus will have to wait. Alternatively, someone can take my patches from LibreELEC, update and submit them. They are in use for a long time. Best regards, Jernej > > Hope I'm making sense here :) > > Thanks, > Ezequiel > > > Best regards, > > Jernej > > > > > > > > > * - __u8 > > > > - ``nal_unit_type`` > > > > - > > > > @@ -3422,28 +3455,20 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > > > * - __u8 > > > > - ``pic_struct`` > > > > - > > > > - * - __u8 > > > > - - ``num_active_dpb_entries`` > > > > - - The number of entries in ``dpb``. > > > > > > Need to explain in the commit description why this field is moved. > > > > > > > * - __u8 > > > > - ``ref_idx_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > - The list of L0 reference elements as indices in the DPB. > > > > * - __u8 > > > > - ``ref_idx_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > - The list of L1 reference elements as indices in the DPB. > > > > + * - __u16 > > > > + - ``short_term_ref_pic_set_size`` > > > > + > > > > > > Not used. > > > > > > > - > > > > + * - __u16 > > > > + - ``long_term_ref_pic_set_size`` > > > > + - > > > > > > Not used. > > > > > > > * - __u8 > > > > - - ``num_rps_poc_st_curr_before`` > > > > - - The number of reference pictures in the short-term set that come > > before > > > > - the current frame. > > > > > > If this matches NumPocStCurrBefore from section 8.3.2 "Decoding process for > > reference picture set" > > > then I would document that. And perhaps rename it to num_poc_st_curr_before. > > > > > > > - * - __u8 > > > > - - ``num_rps_poc_st_curr_after`` > > > > - - The number of reference pictures in the short-term set that come > > after > > > > - the current frame. > > > > > > Ditto. > > > > > > > - * - __u8 > > > > - - ``num_rps_poc_lt_curr`` > > > > - - The number of reference pictures in the long-term set. > > > > > > Ditto. > > > > > > Also, I'd like the changes that move fields from > > V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS > > > to the new V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS control, to be in their > > > patch. > > > > > > That will allow us to put in the commit description a proper > > > explanation of why are fields being moved. Nothing fancy, simply > > > explaining that these variables come from section 8.3.2 > > > "Decoding process for reference picture set", which describes > > > a process invoked once per picture, so they are not per-slice. > > > > > > > - * - __u8 > > > > - - ``padding[7]`` > > > > + - ``padding`` > > > > - Applications and drivers must set this to zero. > > > > * - struct :c:type:`v4l2_hevc_dpb_entry` > > > > - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > @@ -3646,3 +3671,74 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - > > > > so this has to come from client. > > > > This is applicable to H264 and valid Range is from 0 to 63. > > > > Source Rec. ITU-T H.264 (06/2019); G.7.4.1.1, G.8.8.1. > > > > + > > > > +``V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS (struct)`` > > > > + Specifies various decode parameters, especially the references picture > > order > > > > + count (POC) for all the lists (short, long, before, current, after) > > and the > > > > + number of entries for each of them. > > > > + These parameters are defined according to :ref:`hevc`. > > > > + They are described in section 8.3 "Slice decoding process" of the > > > > + specification. > > > > + > > > > +.. c:type:: v4l2_ctrl_hevc_decode_params > > > > + > > > > +.. cssclass:: longtable > > > > + > > > > +.. flat-table:: struct v4l2_ctrl_hevc_decode_params > > > > + :header-rows: 0 > > > > + :stub-columns: 0 > > > > + :widths: 1 1 2 > > > > + > > > > + * - __s32 > > > > + - ``pic_order_cnt_val`` > > > > + - > > > > > > Can be documented as: > > > > > > """ > > > PicOrderCntVal as described in section 8.3.1 "Decoding process > > > for picture order count" of the specification. > > > """ > > > > > > Note that snake case is used to match the kernel style, > > > but other than that we try to keep the HEVC spec variable > > > names. > > > > > > > + * - __u8 > > > > + - ``num_active_dpb_entries`` > > > > + - The number of entries in ``dpb``. > > > > + * - struct :c:type:`v4l2_hevc_dpb_entry` > > > > + - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > + - The decoded picture buffer, for meta-data about reference frames. > > > > > > The DPB is here, but it seems it's also in the slice control? > > > > > > > + * - __u8 > > > > + - ``num_rps_poc_st_curr_before`` > > > > + - The number of reference pictures in the short-term set that come > > before > > > > + the current frame. > > > > + * - __u8 > > > > + - ``num_rps_poc_st_curr_after`` > > > > + - The number of reference pictures in the short-term set that come > > after > > > > + the current frame. > > > > + * - __u8 > > > > + - ``num_rps_poc_lt_curr`` > > > > + - The number of reference pictures in the long-term set. > > > > + * - __u8 > > > > + - ``rps_st_curr_before[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > + - > > > > + * - __u8 > > > > + - ``rps_st_curr_after[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > + - > > > > + * - __u8 > > > > + - ``rps_lt_curr[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > + - > > > > > > Could you document these as well? > > > > > > Thanks a lot, > > > Ezequiel > > > > > > > > > > > > >
On Thu, 25 Feb 2021 19:05:55 +0100, you wrote: >Dne ?etrtek, 25. februar 2021 ob 18:34:48 CET je Ezequiel Garcia napisal(a): >> Hey Jernej, >> >> On Thu, 2021-02-25 at 18:01 +0100, Jernej Škrabec wrote: >> > Hi Ezequiel, >> > >> > Dne ?etrtek, 25. februar 2021 ob 14:09:52 CET je Ezequiel Garcia >napisal(a): >> > > Hi Benjamin, >> > > >> > > Thanks for the good work. >> > > >> > > On Mon, 2021-02-22 at 13:23 +0100, Benjamin Gaignard wrote: >> > > > The H.265 ITU specification (section 7.4) define the general >> > > > slice segment header semantics. >> > > > Modified/added fields are: >> > > > - video_parameter_set_id: (7.4.3.1) identifies the VPS for >> > > > reference by other syntax elements. >> > > > - seq_parameter_set_id: (7.4.3.2.1) specifies the value of >> > > > the vps_video_parameter_set_id of the active VPS. >> > > > - chroma_format_idc: (7.4.3.2.1) specifies the chroma sampling >> > > > relative to the luma sampling >> > > > - pic_parameter_set_id: (7.4.3.3.1) identifies the PPS for >> > > > reference by other syntax elements >> > > > - num_ref_idx_l0_default_active_minus1: (7.4.3.3.1) specifies >> > > > the inferred value of num_ref_idx_l0_active_minus1 >> > > > - num_ref_idx_l1_default_active_minus1: (7.4.3.3.1) specifies >> > > > the inferred value of num_ref_idx_l1_active_minus1 >> > > > - slice_segment_addr: (7.4.7.1) specifies the address of >> > > > the first coding tree block in the slice segment >> > > > - num_entry_point_offsets: (7.4.7.1) specifies the number of >> > > > entry_point_offset_minus1[ i ] syntax elements in the slice header >> > > > >> > > > Add HEVC decode params contains the information used in section >> > > > "8.3 Slice decoding process" of the specification to let the hardware >> > > > perform decoding of a slices. >> > > > >> > > > Adapt Cedrus driver according to these changes. >> > > > >> > > > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> >> > > > --- >> > > > version 3: >> > > > - Add documentation about the new structuers and fields. >> > > > >> > > > version 2: >> > > > - remove all change related to scaling >> > > > - squash commits to a coherent split >> > > > - be more verbose about the added fields >> > > > >> > > > .../media/v4l/ext-ctrls-codec.rst | 126 ++++++++++++++ >+--- >> > > > .../media/v4l/vidioc-queryctrl.rst | 6 + >> > > > drivers/media/v4l2-core/v4l2-ctrls.c | 26 +++- >> > > > drivers/staging/media/sunxi/cedrus/cedrus.c | 6 + >> > > > drivers/staging/media/sunxi/cedrus/cedrus.h | 1 + >> > > > .../staging/media/sunxi/cedrus/cedrus_dec.c | 2 + >> > > > .../staging/media/sunxi/cedrus/cedrus_h265.c | 6 +- >> > > > include/media/hevc-ctrls.h | 45 +++++-- >> > > > 8 files changed, 186 insertions(+), 32 deletions(-) >> > > > >> > > > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >b/ >> > Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >> > > > index 00944e97d638..5e6d77e858c0 100644 >> > > > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >> > > > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst >> > > > @@ -3109,6 +3109,15 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - >> > > > :stub-columns: 0 >> > > > :widths: 1 1 2 >> > > > >> > > > + * - __u8 >> > > > + - ``video_parameter_set_id`` >> > > > + - Identifies the VPS for reference by other syntax elements >> > > > + * - __u8 >> > > > + - ``seq_parameter_set_id?`` >> > > > + - Specifies the value of the vps_video_parameter_set_id of the >> > active VPS >> > > > + * - __u8 >> > > > + - ``chroma_format_idc`` >> > > > + - Specifies the chroma sampling relative to the luma sampling >> > > >> > > None of these fields seem needed for the Hantro G2 driver, >> > > so I suggest you drop them for now. >> > > >> > > > * - __u16 >> > > > - ``pic_width_in_luma_samples`` >> > > > - >> > > > @@ -3172,6 +3181,9 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - >> > > > * - __u8 >> > > > - ``chroma_format_idc`` >> > > > - >> > > > + * - __u8 >> > > > + - ``num_slices`` >> > > > + >> > > >> > > Not used, but also doesn't seem part of the SPS syntax. If we have to >> > > pass the number of slices, we'll need another mechanism. >> > > >> > > > - >> > > > * - __u64 >> > > > - ``flags`` >> > > > - See :ref:`Sequence Parameter Set Flags <hevc_sps_flags>` >> > > > @@ -3231,9 +3243,18 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - >> > > > :stub-columns: 0 >> > > > :widths: 1 1 2 >> > > > >> > > > + * - __u8 >> > > > + - ``pic_parameter_set_id`` >> > > > + - Identifies the PPS for reference by other syntax elements >> > > >> > > Not used. >> > > >> > > > * - __u8 >> > > > - ``num_extra_slice_header_bits`` >> > > > - >> > > > + * - __u8 >> > > > + - ``num_ref_idx_l0_default_active_minus1`` >> > > > + - Specifies the inferred value of num_ref_idx_l0_active_minus1 >> > > > + * - __u8 >> > > > + - ``num_ref_idx_l1_default_active_minus1`` >> > > > + - Specifies the inferred value of num_ref_idx_l1_active_minus1 >> > > > * - __s8 >> > > > - ``init_qp_minus26`` >> > > > - >> > > > @@ -3342,6 +3363,12 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - >> > > > * - ``V4L2_HEVC_PPS_FLAG_SLICE_SEGMENT_HEADER_EXTENSION_PRESENT`` >> > > > - 0x00040000 >> > > > - >> > > > + * - ``V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT`` >> > > > + - 0x00080000 >> > > > + - >> > > > + * - ``V4L2_HEVC_PPS_FLAG_UNIFORM_SPACING`` >> > > > + - 0x00100000 >> > > > + - >> > > > >> > > >> > > I suggest to do all the PPS control changes in a separate patch, >> > > feels easier to review and cleaner as you can explain the >> > > changes with more detail in the commit description. >> > > >> > > Looking at the PPS syntax for tiles, I'm wondering if these >> > > deserve their own control, which would be used if tiles are enabled, >> > > i.e. V4L2_HEVC_PPS_FLAG_TILES_ENABLED is set. >> > > >> > > __u8 >num_tile_columns_minus1; >> > > __u8 >num_tile_rows_minus1; >> > > __u8 >column_width_minus1[20]; >> > > __u8 row_height_minus1[22]; >> > > >> > > Not something we necessarily have to tackle now. >> > > >> > > > ``V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS (struct)`` >> > > > Specifies various slice-specific parameters, especially from the >NAL >> > unit >> > > > @@ -3366,6 +3393,12 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - >> > > > * - __u32 >> > > > - ``data_bit_offset`` >> > > > - Offset (in bits) to the video data in the current slice data. >> > > > + * - __u32 >> > > > + - ``slice_segment_addr`` >> > > > + - Specifies the address of the first coding tree block in the >slice >> > segment >> > > >> > > Not used. >> > > >> > > > + * - __u32 >> > > > + - ``num_entry_point_offsets`` >> > > > + - Specifies the number of entry_point_offset_minus1[ i ] syntax >> > elements in the slice header >> > > >> > > Not used. >> > >> > While above two fields may not be used in Hantro, they are for sure useful >for >> > Cedrus and RPi4. I would like to keep them, otherwise with such approach >HEVC >> > will stay in staging for a long time. I'm still baffled why scaling matrix >> > control was dropped. It would fit well in Cedrus and RPi4 driver and after >a >> > quick look, it seems that it was used in driver in later patch. >> > >> >> I'd like to make sure each modification we are making to the uAPI >> goes in the right direction, that is in the direction of moving >> the API out of staging. >> >> Since reviewing each field is quite hard, and opens some discussions, >> I wanted to keep this patchset specific to what's needed for Hantro G2. >> >> The Scaling matrix control is certainly a good one, as well as the ones >> needed for Cedrus and RPi4. However, I feel it's better to discuss >> them in their own "uAPI review" series so we can review all the changes >> with an API hat. >> >> This way we decouple the Hantro G2 discussion and work from the API work. >> >> Also please feel free to submit RFC patches fo Cedrus and RPi4 >> (API and driver changes). We can certainly start the discussion around that, >> with driver changes in context. > >I don't know much about RPi4 driver, only few implementation details, so >you'll have to ping developer who wrote it. Regarding HEVC on Cedrus - it has >one pain point - it needs entry point table which in turn needs support for >variable arrays in order to be feasable AFAIK. I don't plan to develop that. >Patches for scaling matrix and segment address were sent a bit more than a >year ago but were turned down because they change control structures (among >other things). Sorry to say, but I work on other things now, so Cedrus will >have to wait. Alternatively, someone can take my patches from LibreELEC, >update and submit them. They are in use for a long time. It seems to me that H.265 should be the source for what fields are needed in the uapi - not whatever happens to be supported by current h/w. The standard defines the list of fields that can occur in the parameter sets and headers, and everything that is needed to decode any slice_seqgment_data should be in the upai. Eventually all those fields are going to be needed (they aren't in the standard just to look pretty) and given the reluctance I've observed to change the uapi once released they should be there from the start. Now some hardware requires more fields that aren't in the standard - those can (and should) be added in h/w specific extensions. Regards JC >Best regards, >Jernej > >> >> Hope I'm making sense here :) >> >> Thanks, >> Ezequiel >> >> > Best regards, >> > Jernej >> > >> > > >> > > > * - __u8 >> > > > - ``nal_unit_type`` >> > > > - >> > > > @@ -3422,28 +3455,20 @@ enum v4l2_mpeg_video_hevc_size_of_length_field >- >> > > > * - __u8 >> > > > - ``pic_struct`` >> > > > - >> > > > - * - __u8 >> > > > - - ``num_active_dpb_entries`` >> > > > - - The number of entries in ``dpb``. >> > > >> > > Need to explain in the commit description why this field is moved. >> > > >> > > > * - __u8 >> > > > - ``ref_idx_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` >> > > > - The list of L0 reference elements as indices in the DPB. >> > > > * - __u8 >> > > > - ``ref_idx_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` >> > > > - The list of L1 reference elements as indices in the DPB. >> > > > + * - __u16 >> > > > + - ``short_term_ref_pic_set_size`` >> > > > + >> > > >> > > Not used. >> > > >> > > > - >> > > > + * - __u16 >> > > > + - ``long_term_ref_pic_set_size`` >> > > > + - >> > > >> > > Not used. >> > > >> > > > * - __u8 >> > > > - - ``num_rps_poc_st_curr_before`` >> > > > - - The number of reference pictures in the short-term set that >come >> > before >> > > > - the current frame. >> > > >> > > If this matches NumPocStCurrBefore from section 8.3.2 "Decoding process >for >> > reference picture set" >> > > then I would document that. And perhaps rename it to >num_poc_st_curr_before. >> > > >> > > > - * - __u8 >> > > > - - ``num_rps_poc_st_curr_after`` >> > > > - - The number of reference pictures in the short-term set that >come >> > after >> > > > - the current frame. >> > > >> > > Ditto. >> > > >> > > > - * - __u8 >> > > > - - ``num_rps_poc_lt_curr`` >> > > > - - The number of reference pictures in the long-term set. >> > > >> > > Ditto. >> > > >> > > Also, I'd like the changes that move fields from >> > V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS >> > > to the new V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS control, to be in >their >> > > patch. >> > > >> > > That will allow us to put in the commit description a proper >> > > explanation of why are fields being moved. Nothing fancy, simply >> > > explaining that these variables come from section 8.3.2 >> > > "Decoding process for reference picture set", which describes >> > > a process invoked once per picture, so they are not per-slice. >> > > >> > > > - * - __u8 >> > > > - - ``padding[7]`` >> > > > + - ``padding`` >> > > > - Applications and drivers must set this to zero. >> > > > * - struct :c:type:`v4l2_hevc_dpb_entry` >> > > > - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` >> > > > @@ -3646,3 +3671,74 @@ enum v4l2_mpeg_video_hevc_size_of_length_field - >> > > > so this has to come from client. >> > > > This is applicable to H264 and valid Range is from 0 to 63. >> > > > Source Rec. ITU-T H.264 (06/2019); G.7.4.1.1, G.8.8.1. >> > > > + >> > > > +``V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS (struct)`` >> > > > + Specifies various decode parameters, especially the references >picture >> > order >> > > > + count (POC) for all the lists (short, long, before, current, >after) >> > and the >> > > > + number of entries for each of them. >> > > > + These parameters are defined according to :ref:`hevc`. >> > > > + They are described in section 8.3 "Slice decoding process" of the >> > > > + specification. >> > > > + >> > > > +.. c:type:: v4l2_ctrl_hevc_decode_params >> > > > + >> > > > +.. cssclass:: longtable >> > > > + >> > > > +.. flat-table:: struct v4l2_ctrl_hevc_decode_params >> > > > + :header-rows: 0 >> > > > + :stub-columns: 0 >> > > > + :widths: 1 1 2 >> > > > + >> > > > + * - __s32 >> > > > + - ``pic_order_cnt_val`` >> > > > + - >> > > >> > > Can be documented as: >> > > >> > > """ >> > > PicOrderCntVal as described in section 8.3.1 "Decoding process >> > > for picture order count" of the specification. >> > > """ >> > > >> > > Note that snake case is used to match the kernel style, >> > > but other than that we try to keep the HEVC spec variable >> > > names. >> > > >> > > > + * - __u8 >> > > > + - ``num_active_dpb_entries`` >> > > > + - The number of entries in ``dpb``. >> > > > + * - struct :c:type:`v4l2_hevc_dpb_entry` >> > > > + - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` >> > > > + - The decoded picture buffer, for meta-data about reference >frames. >> > > >> > > The DPB is here, but it seems it's also in the slice control? >> > > >> > > > + * - __u8 >> > > > + - ``num_rps_poc_st_curr_before`` >> > > > + - The number of reference pictures in the short-term set that >come >> > before >> > > > + the current frame. >> > > > + * - __u8 >> > > > + - ``num_rps_poc_st_curr_after`` >> > > > + - The number of reference pictures in the short-term set that >come >> > after >> > > > + the current frame. >> > > > + * - __u8 >> > > > + - ``num_rps_poc_lt_curr`` >> > > > + - The number of reference pictures in the long-term set. >> > > > + * - __u8 >> > > > + - ``rps_st_curr_before[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` >> > > > + - >> > > > + * - __u8 >> > > > + - ``rps_st_curr_after[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` >> > > > + - >> > > > + * - __u8 >> > > > + - ``rps_lt_curr[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` >> > > > + - >> > > >> > > Could you document these as well? >> > > >> > > Thanks a lot, >> > > Ezequiel >> > > >> > > >> > >> > >> >> >> >
Le jeudi 25 février 2021 à 18:34 +0000, John Cox a écrit : > On Thu, 25 Feb 2021 19:05:55 +0100, you wrote: > > > Dne ?etrtek, 25. februar 2021 ob 18:34:48 CET je Ezequiel Garcia napisal(a): > > > Hey Jernej, > > > > > > On Thu, 2021-02-25 at 18:01 +0100, Jernej Škrabec wrote: > > > > Hi Ezequiel, > > > > > > > > Dne ?etrtek, 25. februar 2021 ob 14:09:52 CET je Ezequiel Garcia > > napisal(a): > > > > > Hi Benjamin, > > > > > > > > > > Thanks for the good work. > > > > > > > > > > On Mon, 2021-02-22 at 13:23 +0100, Benjamin Gaignard wrote: > > > > > > The H.265 ITU specification (section 7.4) define the general > > > > > > slice segment header semantics. > > > > > > Modified/added fields are: > > > > > > - video_parameter_set_id: (7.4.3.1) identifies the VPS for > > > > > > reference by other syntax elements. > > > > > > - seq_parameter_set_id: (7.4.3.2.1) specifies the value of > > > > > > the vps_video_parameter_set_id of the active VPS. > > > > > > - chroma_format_idc: (7.4.3.2.1) specifies the chroma sampling > > > > > > relative to the luma sampling > > > > > > - pic_parameter_set_id: (7.4.3.3.1) identifies the PPS for > > > > > > reference by other syntax elements > > > > > > - num_ref_idx_l0_default_active_minus1: (7.4.3.3.1) specifies > > > > > > the inferred value of num_ref_idx_l0_active_minus1 > > > > > > - num_ref_idx_l1_default_active_minus1: (7.4.3.3.1) specifies > > > > > > the inferred value of num_ref_idx_l1_active_minus1 > > > > > > - slice_segment_addr: (7.4.7.1) specifies the address of > > > > > > the first coding tree block in the slice segment > > > > > > - num_entry_point_offsets: (7.4.7.1) specifies the number of > > > > > > entry_point_offset_minus1[ i ] syntax elements in the slice header > > > > > > > > > > > > Add HEVC decode params contains the information used in section > > > > > > "8.3 Slice decoding process" of the specification to let the > > > > > > hardware > > > > > > perform decoding of a slices. > > > > > > > > > > > > Adapt Cedrus driver according to these changes. > > > > > > > > > > > > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> > > > > > > --- > > > > > > version 3: > > > > > > - Add documentation about the new structuers and fields. > > > > > > > > > > > > version 2: > > > > > > - remove all change related to scaling > > > > > > - squash commits to a coherent split > > > > > > - be more verbose about the added fields > > > > > > > > > > > > .../media/v4l/ext-ctrls-codec.rst | 126 ++++++++++++++ > > +--- > > > > > > .../media/v4l/vidioc-queryctrl.rst | 6 + > > > > > > drivers/media/v4l2-core/v4l2-ctrls.c | 26 +++- > > > > > > drivers/staging/media/sunxi/cedrus/cedrus.c | 6 + > > > > > > drivers/staging/media/sunxi/cedrus/cedrus.h | 1 + > > > > > > .../staging/media/sunxi/cedrus/cedrus_dec.c | 2 + > > > > > > .../staging/media/sunxi/cedrus/cedrus_h265.c | 6 +- > > > > > > include/media/hevc-ctrls.h | 45 +++++-- > > > > > > 8 files changed, 186 insertions(+), 32 deletions(-) > > > > > > > > > > > > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls- > > > > > > codec.rst > > b/ > > > > Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > > > > > index 00944e97d638..5e6d77e858c0 100644 > > > > > > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > > > > > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst > > > > > > @@ -3109,6 +3109,15 @@ enum > > > > > > v4l2_mpeg_video_hevc_size_of_length_field - > > > > > > :stub-columns: 0 > > > > > > :widths: 1 1 2 > > > > > > > > > > > > + * - __u8 > > > > > > + - ``video_parameter_set_id`` > > > > > > + - Identifies the VPS for reference by other syntax elements > > > > > > + * - __u8 > > > > > > + - ``seq_parameter_set_id?`` > > > > > > + - Specifies the value of the vps_video_parameter_set_id of > > > > > > the > > > > active VPS > > > > > > + * - __u8 > > > > > > + - ``chroma_format_idc`` > > > > > > + - Specifies the chroma sampling relative to the luma sampling > > > > > > > > > > None of these fields seem needed for the Hantro G2 driver, > > > > > so I suggest you drop them for now. > > > > > > > > > > > * - __u16 > > > > > > - ``pic_width_in_luma_samples`` > > > > > > - > > > > > > @@ -3172,6 +3181,9 @@ enum v4l2_mpeg_video_hevc_size_of_length_field > > > > > > - > > > > > > * - __u8 > > > > > > - ``chroma_format_idc`` > > > > > > - > > > > > > + * - __u8 > > > > > > + - ``num_slices`` > > > > > > + > > > > > > > > > > Not used, but also doesn't seem part of the SPS syntax. If we have to > > > > > pass the number of slices, we'll need another mechanism. > > > > > > > > > > > - > > > > > > * - __u64 > > > > > > - ``flags`` > > > > > > - See :ref:`Sequence Parameter Set Flags <hevc_sps_flags>` > > > > > > @@ -3231,9 +3243,18 @@ enum > > > > > > v4l2_mpeg_video_hevc_size_of_length_field - > > > > > > :stub-columns: 0 > > > > > > :widths: 1 1 2 > > > > > > > > > > > > + * - __u8 > > > > > > + - ``pic_parameter_set_id`` > > > > > > + - Identifies the PPS for reference by other syntax elements > > > > > > > > > > Not used. > > > > > > > > > > > * - __u8 > > > > > > - ``num_extra_slice_header_bits`` > > > > > > - > > > > > > + * - __u8 > > > > > > + - ``num_ref_idx_l0_default_active_minus1`` > > > > > > + - Specifies the inferred value of > > > > > > num_ref_idx_l0_active_minus1 > > > > > > + * - __u8 > > > > > > + - ``num_ref_idx_l1_default_active_minus1`` > > > > > > + - Specifies the inferred value of > > > > > > num_ref_idx_l1_active_minus1 > > > > > > * - __s8 > > > > > > - ``init_qp_minus26`` > > > > > > - > > > > > > @@ -3342,6 +3363,12 @@ enum > > > > > > v4l2_mpeg_video_hevc_size_of_length_field - > > > > > > * - > > > > > > ``V4L2_HEVC_PPS_FLAG_SLICE_SEGMENT_HEADER_EXTENSION_PRESENT`` > > > > > > - 0x00040000 > > > > > > - > > > > > > + * - ``V4L2_HEVC_PPS_FLAG_DEBLOCKING_FILTER_CONTROL_PRESENT`` > > > > > > + - 0x00080000 > > > > > > + - > > > > > > + * - ``V4L2_HEVC_PPS_FLAG_UNIFORM_SPACING`` > > > > > > + - 0x00100000 > > > > > > + - > > > > > > > > > > > > > > > > I suggest to do all the PPS control changes in a separate patch, > > > > > feels easier to review and cleaner as you can explain the > > > > > changes with more detail in the commit description. > > > > > > > > > > Looking at the PPS syntax for tiles, I'm wondering if these > > > > > deserve their own control, which would be used if tiles are enabled, > > > > > i.e. V4L2_HEVC_PPS_FLAG_TILES_ENABLED is set. > > > > > > > > > > __u8 > > num_tile_columns_minus1; > > > > > __u8 > > num_tile_rows_minus1; > > > > > __u8 > > column_width_minus1[20]; > > > > > __u8 row_height_minus1[22]; > > > > > > > > > > Not something we necessarily have to tackle now. > > > > > > > > > > > ``V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS (struct)`` > > > > > > Specifies various slice-specific parameters, especially from > > > > > > the > > NAL > > > > unit > > > > > > @@ -3366,6 +3393,12 @@ enum > > > > > > v4l2_mpeg_video_hevc_size_of_length_field - > > > > > > * - __u32 > > > > > > - ``data_bit_offset`` > > > > > > - Offset (in bits) to the video data in the current slice > > > > > > data. > > > > > > + * - __u32 > > > > > > + - ``slice_segment_addr`` > > > > > > + - Specifies the address of the first coding tree block in the > > slice > > > > segment > > > > > > > > > > Not used. > > > > > > > > > > > + * - __u32 > > > > > > + - ``num_entry_point_offsets`` > > > > > > + - Specifies the number of entry_point_offset_minus1[ i ] > > > > > > syntax > > > > elements in the slice header > > > > > > > > > > Not used. > > > > > > > > While above two fields may not be used in Hantro, they are for sure > > > > useful > > for > > > > Cedrus and RPi4. I would like to keep them, otherwise with such approach > > HEVC > > > > will stay in staging for a long time. I'm still baffled why scaling > > > > matrix > > > > control was dropped. It would fit well in Cedrus and RPi4 driver and > > > > after > > a > > > > quick look, it seems that it was used in driver in later patch. > > > > > > > > > > I'd like to make sure each modification we are making to the uAPI > > > goes in the right direction, that is in the direction of moving > > > the API out of staging. > > > > > > Since reviewing each field is quite hard, and opens some discussions, > > > I wanted to keep this patchset specific to what's needed for Hantro G2. > > > > > > The Scaling matrix control is certainly a good one, as well as the ones > > > needed for Cedrus and RPi4. However, I feel it's better to discuss > > > them in their own "uAPI review" series so we can review all the changes > > > with an API hat. > > > > > > This way we decouple the Hantro G2 discussion and work from the API work. > > > > > > Also please feel free to submit RFC patches fo Cedrus and RPi4 > > > (API and driver changes). We can certainly start the discussion around > > > that, > > > with driver changes in context. > > > > I don't know much about RPi4 driver, only few implementation details, so > > you'll have to ping developer who wrote it. Regarding HEVC on Cedrus - it > > has > > one pain point - it needs entry point table which in turn needs support for > > variable arrays in order to be feasable AFAIK. I don't plan to develop that. > > Patches for scaling matrix and segment address were sent a bit more than a > > year ago but were turned down because they change control structures (among > > other things). Sorry to say, but I work on other things now, so Cedrus will > > have to wait. Alternatively, someone can take my patches from LibreELEC, > > update and submit them. They are in use for a long time. > > It seems to me that H.265 should be the source for what fields are > needed in the uapi - not whatever happens to be supported by current > h/w. The standard defines the list of fields that can occur in the > parameter sets and headers, and everything that is needed to decode > any slice_seqgment_data should be in the upai. Eventually all those > fields are going to be needed (they aren't in the standard just to look > pretty) and given the reluctance I've observed to change the uapi once > released they should be there from the start. > > Now some hardware requires more fields that aren't in the standard - > those can (and should) be added in h/w specific extensions. While this is not wrong, there is obvious bitstream parameters that are not of the HW accelerator domain. We did the work of deciding what to omit in the H264 uAPI, and we'll do that for HEVC for sure. But now is not the time yet. Now the point that you seem to be missing is that Benjamin is trying to stage a driver, not a uAPI. With this third driver, we can have more folks contributing and testing toward our goal of unstaging the uAPI. After this, we'll be able to iteratively add features (like scaling list) to this driver along with the required uAPI and discuss each of these needed API separatly. Note that previous iteration, the driver implementation for the scaling list wasn't correct, and for this reason, the uAPI wasn't being validated. When this is getting stable enough, there will be a final stage were someone will have to pick the uAPI and fill in the blank with remaining field that has a strong probability to be used by later HW WITHIN the supported HEVC profiles et have defined. I emphasis on that because there is a lot of HEVC (and H264) extensions we haven't covered or mentionned, and these will be added with dedicated controls when we have a use case for it of course. Remember that adding controls is not a problem, we need these basic control of the basic decoding, and for sure, over the decade to come we will have to introduce new controls for other stuff we haven't supported yet. All this may look like taking forever, but as Jernej states, not everyone can afford contributing upstream. So unless someone step in, this pace is about what we can offer, and we strongly believe that it will converge. I do personnally expect HEVC to take more time as the codec rationales are mostly kept secret, and our answers burried into a mountain of reference code. It's also, if you defocus from the film industry, just one CODEC. Notably, for the web, VP9 is more important, and this will likely puts some shadow on this work. Meawhile, you are strongly encouraged if you can afford it to open the discussion around the RPi4 multi-stage HEVC decoder. While doing this, you could send a patched for staging the RPi4 driver. The benefit would be that we get to update your drivers when we update the uAPI, saving you times, and also giving everyone more data on what is strictly needed. > > Regards > > JC > > > Best regards, > > Jernej > > > > > > > > Hope I'm making sense here :) > > > > > > Thanks, > > > Ezequiel > > > > > > > Best regards, > > > > Jernej > > > > > > > > > > > > > > > * - __u8 > > > > > > - ``nal_unit_type`` > > > > > > - > > > > > > @@ -3422,28 +3455,20 @@ enum > > > > > > v4l2_mpeg_video_hevc_size_of_length_field > > - > > > > > > * - __u8 > > > > > > - ``pic_struct`` > > > > > > - > > > > > > - * - __u8 > > > > > > - - ``num_active_dpb_entries`` > > > > > > - - The number of entries in ``dpb``. > > > > > > > > > > Need to explain in the commit description why this field is moved. > > > > > > > > > > > * - __u8 > > > > > > - ``ref_idx_l0[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > > > - The list of L0 reference elements as indices in the DPB. > > > > > > * - __u8 > > > > > > - ``ref_idx_l1[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > > > - The list of L1 reference elements as indices in the DPB. > > > > > > + * - __u16 > > > > > > + - ``short_term_ref_pic_set_size`` > > > > > > + > > > > > > > > > > Not used. > > > > > > > > > > > - > > > > > > + * - __u16 > > > > > > + - ``long_term_ref_pic_set_size`` > > > > > > + - > > > > > > > > > > Not used. > > > > > > > > > > > * - __u8 > > > > > > - - ``num_rps_poc_st_curr_before`` > > > > > > - - The number of reference pictures in the short-term set that > > come > > > > before > > > > > > - the current frame. > > > > > > > > > > If this matches NumPocStCurrBefore from section 8.3.2 "Decoding > > > > > process > > for > > > > reference picture set" > > > > > then I would document that. And perhaps rename it to > > num_poc_st_curr_before. > > > > > > > > > > > - * - __u8 > > > > > > - - ``num_rps_poc_st_curr_after`` > > > > > > - - The number of reference pictures in the short-term set that > > come > > > > after > > > > > > - the current frame. > > > > > > > > > > Ditto. > > > > > > > > > > > - * - __u8 > > > > > > - - ``num_rps_poc_lt_curr`` > > > > > > - - The number of reference pictures in the long-term set. > > > > > > > > > > Ditto. > > > > > > > > > > Also, I'd like the changes that move fields from > > > > V4L2_CID_MPEG_VIDEO_HEVC_SLICE_PARAMS > > > > > to the new V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS control, to be in > > their > > > > > patch. > > > > > > > > > > That will allow us to put in the commit description a proper > > > > > explanation of why are fields being moved. Nothing fancy, simply > > > > > explaining that these variables come from section 8.3.2 > > > > > "Decoding process for reference picture set", which describes > > > > > a process invoked once per picture, so they are not per-slice. > > > > > > > > > > > - * - __u8 > > > > > > - - ``padding[7]`` > > > > > > + - ``padding`` > > > > > > - Applications and drivers must set this to zero. > > > > > > * - struct :c:type:`v4l2_hevc_dpb_entry` > > > > > > - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > > > @@ -3646,3 +3671,74 @@ enum > > > > > > v4l2_mpeg_video_hevc_size_of_length_field - > > > > > > so this has to come from client. > > > > > > This is applicable to H264 and valid Range is from 0 to 63. > > > > > > Source Rec. ITU-T H.264 (06/2019); G.7.4.1.1, G.8.8.1. > > > > > > + > > > > > > +``V4L2_CID_MPEG_VIDEO_HEVC_DECODE_PARAMS (struct)`` > > > > > > + Specifies various decode parameters, especially the references > > picture > > > > order > > > > > > + count (POC) for all the lists (short, long, before, current, > > after) > > > > and the > > > > > > + number of entries for each of them. > > > > > > + These parameters are defined according to :ref:`hevc`. > > > > > > + They are described in section 8.3 "Slice decoding process" of > > > > > > the > > > > > > + specification. > > > > > > + > > > > > > +.. c:type:: v4l2_ctrl_hevc_decode_params > > > > > > + > > > > > > +.. cssclass:: longtable > > > > > > + > > > > > > +.. flat-table:: struct v4l2_ctrl_hevc_decode_params > > > > > > + :header-rows: 0 > > > > > > + :stub-columns: 0 > > > > > > + :widths: 1 1 2 > > > > > > + > > > > > > + * - __s32 > > > > > > + - ``pic_order_cnt_val`` > > > > > > + - > > > > > > > > > > Can be documented as: > > > > > > > > > > """ > > > > > PicOrderCntVal as described in section 8.3.1 "Decoding process > > > > > for picture order count" of the specification. > > > > > """ > > > > > > > > > > Note that snake case is used to match the kernel style, > > > > > but other than that we try to keep the HEVC spec variable > > > > > names. > > > > > > > > > > > + * - __u8 > > > > > > + - ``num_active_dpb_entries`` > > > > > > + - The number of entries in ``dpb``. > > > > > > + * - struct :c:type:`v4l2_hevc_dpb_entry` > > > > > > + - ``dpb[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > > > + - The decoded picture buffer, for meta-data about reference > > frames. > > > > > > > > > > The DPB is here, but it seems it's also in the slice control? > > > > > > > > > > > + * - __u8 > > > > > > + - ``num_rps_poc_st_curr_before`` > > > > > > + - The number of reference pictures in the short-term set that > > come > > > > before > > > > > > + the current frame. > > > > > > + * - __u8 > > > > > > + - ``num_rps_poc_st_curr_after`` > > > > > > + - The number of reference pictures in the short-term set that > > come > > > > after > > > > > > + the current frame. > > > > > > + * - __u8 > > > > > > + - ``num_rps_poc_lt_curr`` > > > > > > + - The number of reference pictures in the long-term set. > > > > > > + * - __u8 > > > > > > + - ``rps_st_curr_before[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > > > + - > > > > > > + * - __u8 > > > > > > + - ``rps_st_curr_after[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > > > + - > > > > > > + * - __u8 > > > > > > + - ``rps_lt_curr[V4L2_HEVC_DPB_ENTRIES_NUM_MAX]`` > > > > > > + - > > > > > > > > > > Could you document these as well? > > > > > > > > > > Thanks a lot, > > > > > Ezequiel > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >