1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVUTIL_VIDEO_ENC_PARAMS_H
#define AVUTIL_VIDEO_ENC_PARAMS_H
#include <stddef.h>
#include <stdint.h>
#include "libavutil/avassert.h"
#include "libavutil/frame.h"
enum AVVideoEncParamsType {
AV_VIDEO_ENC_PARAMS_NONE = -1,
/**
* VP9 stores:
* - per-frame base (luma AC) quantizer index, exported as AVVideoEncParams.qp
* - deltas for luma DC, chroma AC and chroma DC, exported in the
* corresponding entries in AVVideoEncParams.delta_qp
* - per-segment delta, exported as for each block as AVVideoBlockParams.delta_qp
*
* To compute the resulting quantizer index for a block:
* - for luma AC, add the base qp and the per-block delta_qp, saturating to
* unsigned 8-bit.
* - for luma DC and chroma AC/DC, add the corresponding
* AVVideoBlockParams.delta_qp to the luma AC index, again saturating to
* unsigned 8-bit.
*/
AV_VIDEO_ENC_PARAMS_VP9,
/**
* H.264 stores:
* - in PPS (per-picture):
* * initial QP_Y (luma) value, exported as AVVideoEncParams.qp
* * delta(s) for chroma QP values (same for both, or each separately),
* exported as in the corresponding entries in AVVideoEncParams.delta_qp
* - per-slice QP delta, not exported directly, added to the per-MB value
* - per-MB delta; not exported directly; the final per-MB quantizer
* parameter - QP_Y - minus the value in AVVideoEncParams.qp is exported
* as AVVideoBlockParams.qp_delta.
*/
AV_VIDEO_ENC_PARAMS_H264,
/*
* MPEG-2-compatible quantizer.
*
* Summing the frame-level qp with the per-block delta_qp gives the
* resulting quantizer for the block.
*/
AV_VIDEO_ENC_PARAMS_MPEG2,
};
/**
* Video encoding parameters for a given frame. This struct is allocated along
* with an optional array of per-block AVVideoBlockParams descriptors.
* Must be allocated with av_video_enc_params_alloc().
*/
typedef struct AVVideoEncParams {
/**
* Number of blocks in the array.
*
* May be 0, in which case no per-block information is present. In this case
* the values of blocks_offset / block_size are unspecified and should not
* be accessed.
*/
unsigned int nb_blocks;
/**
* Offset in bytes from the beginning of this structure at which the array
* of blocks starts.
*/
size_t blocks_offset;
/*
* Size of each block in bytes. May not match sizeof(AVVideoBlockParams).
*/
size_t block_size;
/**
* Type of the parameters (the codec they are used with).
*/
enum AVVideoEncParamsType type;
/**
* Base quantisation parameter for the frame. The final quantiser for a
* given block in a given plane is obtained from this value, possibly
* combined with {@code delta_qp} and the per-block delta in a manner
* documented for each type.
*/
int32_t qp;
/**
* Quantisation parameter offset from the base (per-frame) qp for a given
* plane (first index) and AC/DC coefficients (second index).
*/
int32_t delta_qp[4][2];
} AVVideoEncParams;
/**
* Data structure for storing block-level encoding information.
* It is allocated as a part of AVVideoEncParams and should be retrieved with
* av_video_enc_params_block().
*
* sizeof(AVVideoBlockParams) is not a part of the ABI and new fields may be
* added to it.
*/
typedef struct AVVideoBlockParams {
/**
* Distance in luma pixels from the top-left corner of the visible frame
* to the top-left corner of the block.
* Can be negative if top/right padding is present on the coded frame.
*/
int src_x, src_y;
/**
* Width and height of the block in luma pixels.
*/
int w, h;
/**
* Difference between this block's final quantization parameter and the
* corresponding per-frame value.
*/
int32_t delta_qp;
} AVVideoBlockParams;
/**
* Get the block at the specified {@code idx}. Must be between 0 and nb_blocks - 1.
*/
static av_always_inline AVVideoBlockParams*
av_video_enc_params_block(AVVideoEncParams *par, unsigned int idx)
{
av_assert0(idx < par->nb_blocks);
return (AVVideoBlockParams *)((uint8_t *)par + par->blocks_offset +
idx * par->block_size);
}
/**
* Allocates memory for AVVideoEncParams of the given type, plus an array of
* {@code nb_blocks} AVVideoBlockParams and initializes the variables. Can be
* freed with a normal av_free() call.
*
* @param out_size if non-NULL, the size in bytes of the resulting data array is
* written here.
*/
AVVideoEncParams *av_video_enc_params_alloc(enum AVVideoEncParamsType type,
unsigned int nb_blocks, size_t *out_size);
/**
* Allocates memory for AVEncodeInfoFrame plus an array of
* {@code nb_blocks} AVEncodeInfoBlock in the given AVFrame {@code frame}
* as AVFrameSideData of type AV_FRAME_DATA_VIDEO_ENC_PARAMS
* and initializes the variables.
*/
AVVideoEncParams*
av_video_enc_params_create_side_data(AVFrame *frame, enum AVVideoEncParamsType type,
unsigned int nb_blocks);
#endif /* AVUTIL_VIDEO_ENC_PARAMS_H */
|
