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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
|
/*
* Copyright (C) 2004 Michael Niedermayer <michaelni@gmx.at>
*
* 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
*/
#include <math.h>
#include "libavutil/eval.h"
#include "libavutil/imgutils.h"
#include "libavutil/pixdesc.h"
#include "libavutil/opt.h"
#include "libavutil/video_enc_params.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
typedef struct QPContext {
const AVClass *class;
char *qp_expr_str;
int8_t lut[257];
int h, qstride;
int evaluate_per_mb;
} QPContext;
static const char *const var_names[] = { "known", "qp", "x", "y", "w", "h", NULL };
#define OFFSET(x) offsetof(QPContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption qp_options[] = {
{ "qp", "set qp expression", OFFSET(qp_expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(qp);
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
QPContext *s = ctx->priv;
int i;
int ret;
AVExpr *e = NULL;
if (!s->qp_expr_str)
return 0;
ret = av_expr_parse(&e, s->qp_expr_str, var_names, NULL, NULL, NULL, NULL, 0, ctx);
if (ret < 0)
return ret;
s->h = (inlink->h + 15) >> 4;
s->qstride = (inlink->w + 15) >> 4;
for (i = -129; i < 128; i++) {
double var_values[] = { i != -129, i, NAN, NAN, s->qstride, s->h, 0};
double temp_val = av_expr_eval(e, var_values, NULL);
if (isnan(temp_val)) {
if(strchr(s->qp_expr_str, 'x') || strchr(s->qp_expr_str, 'y'))
s->evaluate_per_mb = 1;
else {
av_expr_free(e);
return AVERROR(EINVAL);
}
}
s->lut[i + 129] = lrintf(temp_val);
}
av_expr_free(e);
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
QPContext *s = ctx->priv;
AVFrame *out = NULL;
int ret;
AVFrameSideData *sd_in;
AVVideoEncParams *par_in = NULL;
int8_t in_qp_global = 0;
AVVideoEncParams *par_out;
if (!s->qp_expr_str || ctx->is_disabled)
return ff_filter_frame(outlink, in);
sd_in = av_frame_get_side_data(in, AV_FRAME_DATA_VIDEO_ENC_PARAMS);
if (sd_in && sd_in->size >= sizeof(AVVideoEncParams)) {
par_in = (AVVideoEncParams*)sd_in->data;
// we accept the input QP table only if it is of the MPEG2 type
// and contains either no blocks at all or 16x16 macroblocks
if (par_in->type == AV_VIDEO_ENC_PARAMS_MPEG2 &&
(par_in->nb_blocks == s->h * s->qstride || !par_in->nb_blocks)) {
in_qp_global = par_in->qp;
if (!par_in->nb_blocks)
par_in = NULL;
} else
par_in = NULL;
}
out = av_frame_clone(in);
if (!out) {
ret = AVERROR(ENOMEM);
goto fail;
}
par_out = av_video_enc_params_create_side_data(out, AV_VIDEO_ENC_PARAMS_MPEG2,
(s->evaluate_per_mb || sd_in) ?
s->h * s->qstride : 0);
if (!par_out) {
ret = AVERROR(ENOMEM);
goto fail;
}
#define BLOCK_QP_DELTA(block_idx) \
(par_in ? av_video_enc_params_block(par_in, block_idx)->delta_qp : 0)
if (s->evaluate_per_mb) {
int y, x;
for (y = 0; y < s->h; y++)
for (x = 0; x < s->qstride; x++) {
unsigned int block_idx = y * s->qstride + x;
AVVideoBlockParams *b = av_video_enc_params_block(par_out, block_idx);
double qp = sd_in ? in_qp_global + BLOCK_QP_DELTA(block_idx) : NAN;
double var_values[] = { !!sd_in, qp, x, y, s->qstride, s->h, 0};
double temp_val;
ret = av_expr_parse_and_eval(&temp_val, s->qp_expr_str,
var_names, var_values,
NULL, NULL, NULL, NULL, 0, 0, ctx);
if (ret < 0)
goto fail;
b->delta_qp = lrintf(temp_val);
}
} else if (sd_in) {
int y, x;
for (y = 0; y < s->h; y++)
for (x = 0; x < s->qstride; x++) {
unsigned int block_idx = y * s->qstride + x;
AVVideoBlockParams *b = av_video_enc_params_block(par_out, block_idx);
b->delta_qp = s->lut[129 + (int8_t)(in_qp_global + BLOCK_QP_DELTA(block_idx))];
}
} else {
par_out->qp = s->lut[0];
}
ret = ff_filter_frame(outlink, out);
out = NULL;
fail:
av_frame_free(&in);
av_frame_free(&out);
return ret;
}
static const AVFilterPad qp_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
.config_props = config_input,
},
};
static const AVFilterPad qp_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
};
const AVFilter ff_vf_qp = {
.name = "qp",
.description = NULL_IF_CONFIG_SMALL("Change video quantization parameters."),
.priv_size = sizeof(QPContext),
FILTER_INPUTS(qp_inputs),
FILTER_OUTPUTS(qp_outputs),
.priv_class = &qp_class,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL |
AVFILTER_FLAG_METADATA_ONLY,
};
|
