linux/include/media/v4l2-h264.h

85 lines
2.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Helper functions for H264 codecs.
*
* Copyright (c) 2019 Collabora, Ltd.
*
* Author: Boris Brezillon <boris.brezillon@collabora.com>
*/
#ifndef _MEDIA_V4L2_H264_H
#define _MEDIA_V4L2_H264_H
#include <media/v4l2-ctrls.h>
/**
* 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;
u32 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_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 */