From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AC8CAC76190 for ; Mon, 22 Jul 2019 15:29:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 796D4214C6 for ; Mon, 22 Jul 2019 15:29:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729095AbfGVP32 (ORCPT ); Mon, 22 Jul 2019 11:29:28 -0400 Received: from lb3-smtp-cloud7.xs4all.net ([194.109.24.31]:50243 "EHLO lb3-smtp-cloud7.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728385AbfGVP32 (ORCPT ); Mon, 22 Jul 2019 11:29:28 -0400 Received: from [192.168.2.10] ([46.9.252.75]) by smtp-cloud7.xs4all.net with ESMTPA id paFehcZJT0SBqpaFhhryye; Mon, 22 Jul 2019 17:29:26 +0200 Subject: Re: [PATCH v3 2/3] media: uapi: h264: Add the concept of decoding mode To: Boris Brezillon , Mauro Carvalho Chehab , Hans Verkuil , Laurent Pinchart , Sakari Ailus , linux-media@vger.kernel.org Cc: Tomasz Figa , Nicolas Dufresne , kernel@collabora.com, Paul Kocialkowski , Maxime Ripard , Ezequiel Garcia , Jonas Karlman , Jernej Skrabec , Alexandre Courbot , Thierry Reding References: <20190703122849.6316-1-boris.brezillon@collabora.com> <20190703122849.6316-3-boris.brezillon@collabora.com> From: Hans Verkuil Message-ID: <41031ffb-3c40-9492-5aa2-8c7b738fbc65@xs4all.nl> Date: Mon, 22 Jul 2019 17:29:21 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190703122849.6316-3-boris.brezillon@collabora.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfF+qywAuQ4pU1ZO6JfyqlkYL1eLimkpVjiQxGcF10wZ/8ZuXVCz2fEAPhyaACDA38zDeZ6IB8AdDR58P9Em2uBRaJBM2waHzuUsyvENbCWcvXAikIYqs ekpflgt4WAiSuSx+4MB8m4t0vIv+UOOMszAX0Y9967eh8dT1tW6GE5sY4AT3/5lUDpvb6ard9iXPHPKoGPckwPgJlQ1Gi7Ca6kHDEpYI/9iSU5q11tyam+wY YGdNiShEcIFHpBXSQIgbmiBNdO5zeDuJJiXvWzrziz2NubgrZZ4d+f7C+4FCLjILE/EzvsnMGKtdsHcG/2PfixX3O2+rmwZzlm3Un1HQlkyxilCRdlqGk5ce Su32fi0fhrOEcOqVgih4MpzJ2eZaNcUS3Uyq/d6f49//1o88t0yl8p1g5IiaaGgd60Fmtbsuir/ezfUHyv14Q0tELqFaLMdNlnD4HgOv/CkgxpvI51I094tD QCtEGrMJvSD4GzmbGlbS1SIauMuTy1pCBWdN7MXXTTx2XRnmVgSf6CKM992OHAqcya0sA/TvUk2Owumik7HLHjrT4xwmeqCmbYEqs9EO/Xd7soLQlG1GBCmd SX4Dmj4t6QG1Ze03JZUnxqpKIL/qFtbYhGKavLSuqv93M0RvzvV4LgnkoCJG2DGfKm5h0ubVIjyD5H7ONBpJeowAZcydgg0sIvY86oyBn3QiSQ== Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On 7/3/19 2:28 PM, Boris Brezillon wrote: > Some stateless decoders don't support per-slice decoding (or at least > not in a way that would make them efficient or easy to use). > Let's expose a menu to control and expose the supported decoding modes. > Drivers are allowed to support only one decoding but they can support > both too. > > Signed-off-by: Boris Brezillon > Reviewed-by: Paul Kocialkowski > --- > Changes in v3: > * s/per-{slice,frame} decoding/{slice,frame}-based decoding/ > * Add Paul's R-b > > Changes in v2: > * Allow decoding multiple slices in per-slice decoding mode > * Minor doc improvement/fixes > --- > .../media/uapi/v4l/ext-ctrls-codec.rst | 47 ++++++++++++++++++- > drivers/media/v4l2-core/v4l2-ctrls.c | 9 ++++ > include/media/h264-ctrls.h | 13 +++++ > 3 files changed, 68 insertions(+), 1 deletion(-) > > diff --git a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst > index 3ae1367806cf..47ba2d057a92 100644 > --- a/Documentation/media/uapi/v4l/ext-ctrls-codec.rst > +++ b/Documentation/media/uapi/v4l/ext-ctrls-codec.rst > @@ -1748,6 +1748,14 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type - > * - __u32 > - ``size`` > - > + * - __u32 > + - ``start_byte_offset`` > + - Where the slice payload starts in the output buffer. Useful when > + operating in frame-based decoding mode and decoding multi-slice > + content. In this case, the output buffer will contain more than one > + slice and some codecs need to know where each slice starts. Note that > + this offsets points to the beginning of the slice which is supposed to offsets -> offset > + contain an ANNEX B start code Add . at the end of the sentence. I think this is a bit awkward. How about: "Note that the slice at this offset shall start with an ANNEX B start code." I'm assuming it has to actually start with an ANNEX B code? Or should it just 'contain' an ANNEX B code? When in sliced-based decoding mode, what should be used here? I assume that in that case start_byte_offset would be 0, and that the slice shall still begin with an ANNEX B start code? > * - __u32 > - ``header_bit_size`` > - > @@ -1931,7 +1939,10 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type - > - > * - __u16 > - ``num_slices`` > - - Number of slices needed to decode the current frame > + - Number of slices needed to decode the current frame/field. When > + operating in slice-based decoding mode (see > + :c:type:`v4l2_mpeg_video_h264_decoding_mode`), this field > + should always be set to one Add . at the end of the sentence. > * - __u16 > - ``nal_ref_idc`` > - NAL reference ID value coming from the NAL Unit header > @@ -2022,6 +2033,40 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type - > - 0x00000004 > - The DPB entry is a long term reference frame > > +``V4L2_CID_MPEG_VIDEO_H264_DECODING_MODE (enum)`` > + Specifies the decoding mode to use. Currently exposes slice-based and > + frame-based decoding but new modes might be added later on. > + > + .. note:: > + > + This menu control is not yet part of the public kernel API and > + it is expected to change. > + > +.. c:type:: v4l2_mpeg_video_h264_decoding_mode > + > +.. cssclass:: longtable > + > +.. flat-table:: > + :header-rows: 0 > + :stub-columns: 0 > + :widths: 1 1 2 > + > + * - ``V4L2_MPEG_VIDEO_H264_SLICE_BASED_DECODING`` > + - 0 > + - The decoding is done at the slice granularity. > + v4l2_ctrl_h264_decode_params->num_slices can be set to anything between > + 1 and then number of slices that remain to fully decode the then -> the > + frame/field. > + The output buffer should contain > + v4l2_ctrl_h264_decode_params->num_slices slices. > + * - ``V4L2_MPEG_VIDEO_H264_FRAME_BASED_DECODING`` > + - 1 > + - The decoding is done at the frame granularity. > + v4l2_ctrl_h264_decode_params->num_slices should be set to the number of > + slices forming a frame. > + The output buffer should contain all slices needed to decode the > + frame/field. > + > .. _v4l2-mpeg-mpeg2: > > ``V4L2_CID_MPEG_VIDEO_MPEG2_SLICE_PARAMS (struct)`` > diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c > index 471ff5c91f43..70d994be27e1 100644 > --- a/drivers/media/v4l2-core/v4l2-ctrls.c > +++ b/drivers/media/v4l2-core/v4l2-ctrls.c > @@ -394,6 +394,11 @@ const char * const *v4l2_ctrl_get_menu(u32 id) > "Explicit", > NULL, > }; > + static const char * const h264_decoding_mode[] = { > + "Slice-based", > + "Frame-based", based -> Based > + NULL, > + }; > static const char * const mpeg_mpeg2_level[] = { > "Low", > "Main", > @@ -625,6 +630,8 @@ const char * const *v4l2_ctrl_get_menu(u32 id) > return h264_fp_arrangement_type; > case V4L2_CID_MPEG_VIDEO_H264_FMO_MAP_TYPE: > return h264_fmo_map_type; > + case V4L2_CID_MPEG_VIDEO_H264_DECODING_MODE: > + return h264_decoding_mode; > case V4L2_CID_MPEG_VIDEO_MPEG2_LEVEL: > return mpeg_mpeg2_level; > case V4L2_CID_MPEG_VIDEO_MPEG2_PROFILE: > @@ -844,6 +851,7 @@ const char *v4l2_ctrl_get_name(u32 id) > case V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX: return "H264 Scaling Matrix"; > case V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS: return "H264 Slice Parameters"; > case V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS: return "H264 Decode Parameters"; > + case V4L2_CID_MPEG_VIDEO_H264_DECODING_MODE: return "H264 Decoding Mode"; > case V4L2_CID_MPEG_VIDEO_MPEG2_LEVEL: return "MPEG2 Level"; > case V4L2_CID_MPEG_VIDEO_MPEG2_PROFILE: return "MPEG2 Profile"; > case V4L2_CID_MPEG_VIDEO_MPEG4_I_FRAME_QP: return "MPEG4 I-Frame QP Value"; > @@ -1212,6 +1220,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type, > case V4L2_CID_MPEG_VIDEO_H264_VUI_SAR_IDC: > case V4L2_CID_MPEG_VIDEO_H264_SEI_FP_ARRANGEMENT_TYPE: > case V4L2_CID_MPEG_VIDEO_H264_FMO_MAP_TYPE: > + case V4L2_CID_MPEG_VIDEO_H264_DECODING_MODE: > case V4L2_CID_MPEG_VIDEO_MPEG2_LEVEL: > case V4L2_CID_MPEG_VIDEO_MPEG2_PROFILE: > case V4L2_CID_MPEG_VIDEO_MPEG4_LEVEL: > diff --git a/include/media/h264-ctrls.h b/include/media/h264-ctrls.h > index e1404d78d6ff..206fd5ada620 100644 > --- a/include/media/h264-ctrls.h > +++ b/include/media/h264-ctrls.h > @@ -26,6 +26,7 @@ > #define V4L2_CID_MPEG_VIDEO_H264_SCALING_MATRIX (V4L2_CID_MPEG_BASE+1002) > #define V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS (V4L2_CID_MPEG_BASE+1003) > #define V4L2_CID_MPEG_VIDEO_H264_DECODE_PARAMS (V4L2_CID_MPEG_BASE+1004) > +#define V4L2_CID_MPEG_VIDEO_H264_DECODING_MODE (V4L2_CID_MPEG_BASE+1005) > > /* enum v4l2_ctrl_type type values */ > #define V4L2_CTRL_TYPE_H264_SPS 0x0110 > @@ -33,6 +34,12 @@ > #define V4L2_CTRL_TYPE_H264_SCALING_MATRIX 0x0112 > #define V4L2_CTRL_TYPE_H264_SLICE_PARAMS 0x0113 > #define V4L2_CTRL_TYPE_H264_DECODE_PARAMS 0x0114 > +#define V4L2_CTRL_TYPE_H264_DECODING_MODE 0x0115 > + > +enum v4l2_mpeg_video_h264_decoding_mode { > + V4L2_MPEG_VIDEO_H264_SLICE_BASED_DECODING, > + V4L2_MPEG_VIDEO_H264_FRAME_BASED_DECODING, > +}; > > #define V4L2_H264_SPS_CONSTRAINT_SET0_FLAG 0x01 > #define V4L2_H264_SPS_CONSTRAINT_SET1_FLAG 0x02 > @@ -111,6 +118,8 @@ struct v4l2_h264_pred_weight_table { > struct v4l2_h264_weight_factors weight_factors[2]; > }; > > +#define V4L2_H264_MAX_SLICES_PER_FRAME 16 Are there arrays in these compound control structs where this define can be used? Is this define standards-based or a restriction of V4L2? Regards, Hans > + > #define V4L2_H264_SLICE_TYPE_P 0 > #define V4L2_H264_SLICE_TYPE_B 1 > #define V4L2_H264_SLICE_TYPE_I 2 > @@ -125,6 +134,10 @@ struct v4l2_h264_pred_weight_table { > struct v4l2_ctrl_h264_slice_params { > /* Size in bytes, including header */ > __u32 size; > + > + /* Where the slice starts in the output buffer (expressed in bytes). */ > + __u32 start_byte_offset; > + > /* Offset in bits to slice_data() from the beginning of this slice. */ > __u32 header_bit_size; > >