From 624922a2739b96b83aaf1655d0519b41d30140f7 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Sat, 4 Apr 2020 00:13:41 +0200 Subject: media: v4l2-core: Add helpers to build the H264 P/B0/B1 reflists Building those list is a standard procedure described in section '8.2.4 Decoding process for reference picture lists construction' of the H264 specification. We already have 2 drivers needing the same logic (hantro and rkvdec) and I suspect we will soon have more. Let's provide generic helpers to create those lists. Signed-off-by: Boris Brezillon Signed-off-by: Ezequiel Garcia Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- include/media/h264-ctrls.h | 8 ++++- include/media/v4l2-h264.h | 85 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 92 insertions(+), 1 deletion(-) create mode 100644 include/media/v4l2-h264.h (limited to 'include/media') diff --git a/include/media/h264-ctrls.h b/include/media/h264-ctrls.h index 1c6ff7d63bca..080fd1293c42 100644 --- a/include/media/h264-ctrls.h +++ b/include/media/h264-ctrls.h @@ -13,6 +13,12 @@ #include +/* + * Maximum DPB size, as specified by section 'A.3.1 Level limits + * common to the Baseline, Main, and Extended profiles'. + */ +#define V4L2_H264_NUM_DPB_ENTRIES 16 + /* Our pixel format isn't stable at the moment */ #define V4L2_PIX_FMT_H264_SLICE v4l2_fourcc('S', '2', '6', '4') /* H264 parsed slices */ @@ -201,7 +207,7 @@ struct v4l2_h264_dpb_entry { #define V4L2_H264_DECODE_PARAM_FLAG_IDR_PIC 0x01 struct v4l2_ctrl_h264_decode_params { - struct v4l2_h264_dpb_entry dpb[16]; + struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES]; __u16 num_slices; __u16 nal_ref_idc; __s32 top_field_order_cnt; diff --git a/include/media/v4l2-h264.h b/include/media/v4l2-h264.h new file mode 100644 index 000000000000..bc9ebb560ccf --- /dev/null +++ b/include/media/v4l2-h264.h @@ -0,0 +1,85 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Helper functions for H264 codecs. + * + * Copyright (c) 2019 Collabora, Ltd. + * + * Author: Boris Brezillon + */ + +#ifndef _MEDIA_V4L2_H264_H +#define _MEDIA_V4L2_H264_H + +#include + +/** + * struct v4l2_h264_reflist_builder - Reference list builder object + * + * @refs.pic_order_count: reference picture order count + * @refs.frame_num: reference frame number + * @refs.pic_num: reference picture number + * @refs.longterm: set to true for a long term reference + * @refs: array of references + * @cur_pic_order_count: picture order count of the frame being decoded + * @unordered_reflist: unordered list of references. Will be used to generate + * ordered P/B0/B1 lists + * @num_valid: number of valid references in the refs array + * + * This object stores the context of the P/B0/B1 reference list builder. + * This procedure is described in section '8.2.4 Decoding process for reference + * picture lists construction' of the H264 spec. + */ +struct v4l2_h264_reflist_builder { + struct { + s32 pic_order_count; + int frame_num; + u16 pic_num; + u16 longterm : 1; + } refs[V4L2_H264_NUM_DPB_ENTRIES]; + s32 cur_pic_order_count; + u8 unordered_reflist[V4L2_H264_NUM_DPB_ENTRIES]; + u8 num_valid; +}; + +void +v4l2_h264_init_reflist_builder(struct v4l2_h264_reflist_builder *b, + const struct v4l2_ctrl_h264_decode_params *dec_params, + const struct v4l2_ctrl_h264_slice_params *slice_params, + const struct v4l2_ctrl_h264_sps *sps, + const struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES]); + +/** + * v4l2_h264_build_b_ref_lists() - Build the B0/B1 reference lists + * + * @builder: reference list builder context + * @b0_reflist: 16-bytes array used to store the B0 reference list. Each entry + * is an index in the DPB + * @b1_reflist: 16-bytes array used to store the B1 reference list. Each entry + * is an index in the DPB + * + * This functions builds the B0/B1 reference lists. This procedure is described + * in section '8.2.4 Decoding process for reference picture lists construction' + * of the H264 spec. This function can be used by H264 decoder drivers that + * need to pass B0/B1 reference lists to the hardware. + */ +void +v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder, + u8 *b0_reflist, u8 *b1_reflist); + +/** + * v4l2_h264_build_b_ref_lists() - Build the P reference list + * + * @builder: reference list builder context + * @p_reflist: 16-bytes array used to store the P reference list. Each entry + * is an index in the DPB + * + * This functions builds the P reference lists. This procedure is describe in + * section '8.2.4 Decoding process for reference picture lists construction' + * of the H264 spec. This function can be used by H264 decoder drivers that + * need to pass a P reference list to the hardware. + */ +void +v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder, + u8 *reflist); + +#endif /* _MEDIA_V4L2_H264_H */ -- cgit v1.2.3