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
|
/*
* Copyright (c) 2010 Stefano Sabatini
* Copyright (c) 2008 Victor Paesa
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* video presentation timestamp (PTS) modification filter
*/
/* #define DEBUG */
#include "libavutil/eval.h"
#include "libavutil/mathematics.h"
#include "avfilter.h"
static const char *var_names[] = {
"E", ///< Euler number
"INTERLACED", ///< tell if the current frame is interlaced
"N", ///< frame number (starting at zero)
"PHI", ///< golden ratio
"PI", ///< greek pi
"POS", ///< original position in the file of the frame
"PREV_INPTS", ///< previous input PTS
"PREV_OUTPTS", ///< previous output PTS
"PTS", ///< original pts in the file of the frame
"STARTPTS", ///< PTS at start of movie
"TB", ///< timebase
NULL
};
enum var_name {
VAR_E,
VAR_INTERLACED,
VAR_N,
VAR_PHI,
VAR_PI,
VAR_POS,
VAR_PREV_INPTS,
VAR_PREV_OUTPTS,
VAR_PTS,
VAR_STARTPTS,
VAR_TB,
VAR_VARS_NB
};
typedef struct {
AVExpr *expr;
double var_values[VAR_VARS_NB];
} SetPTSContext;
static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
{
SetPTSContext *setpts = ctx->priv;
int ret;
if ((ret = av_expr_parse(&setpts->expr, args ? args : "PTS",
var_names, NULL, NULL, NULL, NULL, 0, ctx)) < 0) {
av_log(ctx, AV_LOG_ERROR, "Error while parsing expression '%s'\n", args);
return ret;
}
setpts->var_values[VAR_E ] = M_E;
setpts->var_values[VAR_N ] = 0.0;
setpts->var_values[VAR_PHI ] = M_PHI;
setpts->var_values[VAR_PI ] = M_PI;
setpts->var_values[VAR_PREV_INPTS ] = NAN;
setpts->var_values[VAR_PREV_OUTPTS] = NAN;
setpts->var_values[VAR_STARTPTS ] = NAN;
return 0;
}
static int config_input(AVFilterLink *inlink)
{
SetPTSContext *setpts = inlink->dst->priv;
setpts->var_values[VAR_TB] = av_q2d(inlink->time_base);
av_log(inlink->src, AV_LOG_INFO, "TB:%f\n", setpts->var_values[VAR_TB]);
return 0;
}
#define D2TS(d) (isnan(d) ? AV_NOPTS_VALUE : (int64_t)(d))
#define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts))
static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
{
SetPTSContext *setpts = inlink->dst->priv;
double d;
AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0);
if (isnan(setpts->var_values[VAR_STARTPTS]))
setpts->var_values[VAR_STARTPTS] = TS2D(inpicref->pts);
setpts->var_values[VAR_INTERLACED] = inpicref->video->interlaced;
setpts->var_values[VAR_PTS ] = TS2D(inpicref->pts);
setpts->var_values[VAR_POS ] = inpicref->pos == -1 ? NAN : inpicref->pos;
d = av_expr_eval(setpts->expr, setpts->var_values, NULL);
outpicref->pts = D2TS(d);
#ifdef DEBUG
av_log(inlink->dst, AV_LOG_DEBUG,
"n:%"PRId64" interlaced:%d pos:%"PRId64" pts:%"PRId64" t:%f -> pts:%"PRId64" t:%f\n",
(int64_t)setpts->var_values[VAR_N],
(int)setpts->var_values[VAR_INTERLACED],
inpicref ->pos,
inpicref ->pts, inpicref ->pts * av_q2d(inlink->time_base),
outpicref->pts, outpicref->pts * av_q2d(inlink->time_base));
#endif
setpts->var_values[VAR_N] += 1.0;
setpts->var_values[VAR_PREV_INPTS ] = TS2D(inpicref ->pts);
setpts->var_values[VAR_PREV_OUTPTS] = TS2D(outpicref->pts);
avfilter_start_frame(inlink->dst->outputs[0], outpicref);
}
static av_cold void uninit(AVFilterContext *ctx)
{
SetPTSContext *setpts = ctx->priv;
av_expr_free(setpts->expr);
setpts->expr = NULL;
}
AVFilter avfilter_vf_setpts = {
.name = "setpts",
.description = NULL_IF_CONFIG_SMALL("Set PTS for the output video frame."),
.init = init,
.uninit = uninit,
.priv_size = sizeof(SetPTSContext),
.inputs = (AVFilterPad[]) {{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_video_buffer = avfilter_null_get_video_buffer,
.config_props = config_input,
.start_frame = start_frame, },
{ .name = NULL }},
.outputs = (AVFilterPad[]) {{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO, },
{ .name = NULL}},
};
|