1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* |
3 | * Helper functions for H264 codecs. |
4 | * |
5 | * Copyright (c) 2019 Collabora, Ltd. |
6 | * |
7 | * Author: Boris Brezillon <boris.brezillon@collabora.com> |
8 | */ |
9 | |
10 | #ifndef _MEDIA_V4L2_H264_H |
11 | #define _MEDIA_V4L2_H264_H |
12 | |
13 | #include <media/v4l2-ctrls.h> |
14 | |
15 | /** |
16 | * struct v4l2_h264_reflist_builder - Reference list builder object |
17 | * |
18 | * @refs.top_field_order_cnt: top field order count |
19 | * @refs.bottom_field_order_cnt: bottom field order count |
20 | * @refs.frame_num: reference frame number |
21 | * @refs.longterm: set to true for a long term reference |
22 | * @refs: array of references |
23 | * @cur_pic_order_count: picture order count of the frame being decoded |
24 | * @cur_pic_fields: fields present in the frame being decoded |
25 | * @unordered_reflist: unordered list of references. Will be used to generate |
26 | * ordered P/B0/B1 lists |
27 | * @num_valid: number of valid references in the refs array |
28 | * |
29 | * This object stores the context of the P/B0/B1 reference list builder. |
30 | * This procedure is described in section '8.2.4 Decoding process for reference |
31 | * picture lists construction' of the H264 spec. |
32 | */ |
33 | struct v4l2_h264_reflist_builder { |
34 | struct { |
35 | s32 top_field_order_cnt; |
36 | s32 bottom_field_order_cnt; |
37 | int frame_num; |
38 | u16 longterm : 1; |
39 | } refs[V4L2_H264_NUM_DPB_ENTRIES]; |
40 | |
41 | s32 cur_pic_order_count; |
42 | u8 cur_pic_fields; |
43 | |
44 | struct v4l2_h264_reference unordered_reflist[V4L2_H264_REF_LIST_LEN]; |
45 | u8 num_valid; |
46 | }; |
47 | |
48 | void |
49 | v4l2_h264_init_reflist_builder(struct v4l2_h264_reflist_builder *b, |
50 | const struct v4l2_ctrl_h264_decode_params *dec_params, |
51 | const struct v4l2_ctrl_h264_sps *sps, |
52 | const struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES]); |
53 | |
54 | /** |
55 | * v4l2_h264_build_b_ref_lists() - Build the B0/B1 reference lists |
56 | * |
57 | * @builder: reference list builder context |
58 | * @b0_reflist: 32 sized array used to store the B0 reference list. Each entry |
59 | * is a v4l2_h264_reference structure |
60 | * @b1_reflist: 32 sized array used to store the B1 reference list. Each entry |
61 | * is a v4l2_h264_reference structure |
62 | * |
63 | * This functions builds the B0/B1 reference lists. This procedure is described |
64 | * in section '8.2.4 Decoding process for reference picture lists construction' |
65 | * of the H264 spec. This function can be used by H264 decoder drivers that |
66 | * need to pass B0/B1 reference lists to the hardware. |
67 | */ |
68 | void |
69 | v4l2_h264_build_b_ref_lists(const struct v4l2_h264_reflist_builder *builder, |
70 | struct v4l2_h264_reference *b0_reflist, |
71 | struct v4l2_h264_reference *b1_reflist); |
72 | |
73 | /** |
74 | * v4l2_h264_build_p_ref_list() - Build the P reference list |
75 | * |
76 | * @builder: reference list builder context |
77 | * @reflist: 32 sized array used to store the P reference list. Each entry |
78 | * is a v4l2_h264_reference structure |
79 | * |
80 | * This functions builds the P reference lists. This procedure is describe in |
81 | * section '8.2.4 Decoding process for reference picture lists construction' |
82 | * of the H264 spec. This function can be used by H264 decoder drivers that |
83 | * need to pass a P reference list to the hardware. |
84 | */ |
85 | void |
86 | v4l2_h264_build_p_ref_list(const struct v4l2_h264_reflist_builder *builder, |
87 | struct v4l2_h264_reference *reflist); |
88 | |
89 | #endif /* _MEDIA_V4L2_H264_H */ |
90 | |