2 * Copyright (c) 2010 Stefano Sabatini
3 * Copyright (c) 2008 Victor Paesa
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * video presentation timestamp (PTS) modification filter
29 #include "libavutil/eval.h"
30 #include "libavutil/internal.h"
31 #include "libavutil/mathematics.h"
32 #include "libavutil/time.h"
37 static const char *const var_names[] = {
38 "E", ///< Euler number
39 "INTERLACED", ///< tell if the current frame is interlaced
40 "N", ///< frame number (starting at zero)
41 "PHI", ///< golden ratio
43 "PREV_INPTS", ///< previous input PTS
44 "PREV_OUTPTS", ///< previous output PTS
45 "PTS", ///< original pts in the file of the frame
46 "STARTPTS", ///< PTS at start of movie
48 "RTCTIME", ///< wallclock (RTC) time in micro seconds
49 "RTCSTART", ///< wallclock (RTC) time at the start of the movie in micro seconds
71 double var_values[VAR_VARS_NB];
74 static av_cold int init(AVFilterContext *ctx, const char *args)
76 SetPTSContext *setpts = ctx->priv;
79 if ((ret = av_expr_parse(&setpts->expr, args ? args : "PTS",
80 var_names, NULL, NULL, NULL, NULL, 0, ctx)) < 0) {
81 av_log(ctx, AV_LOG_ERROR, "Error while parsing expression '%s'\n", args);
85 setpts->var_values[VAR_E ] = M_E;
86 setpts->var_values[VAR_N ] = 0.0;
87 setpts->var_values[VAR_PHI ] = M_PHI;
88 setpts->var_values[VAR_PI ] = M_PI;
89 setpts->var_values[VAR_PREV_INPTS ] = NAN;
90 setpts->var_values[VAR_PREV_OUTPTS] = NAN;
91 setpts->var_values[VAR_STARTPTS ] = NAN;
95 static int config_input(AVFilterLink *inlink)
97 SetPTSContext *setpts = inlink->dst->priv;
99 setpts->var_values[VAR_TB] = av_q2d(inlink->time_base);
100 setpts->var_values[VAR_RTCSTART] = av_gettime();
102 av_log(inlink->src, AV_LOG_VERBOSE, "TB:%f\n", setpts->var_values[VAR_TB]);
106 #define D2TS(d) (isnan(d) ? AV_NOPTS_VALUE : (int64_t)(d))
107 #define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts))
109 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
111 SetPTSContext *setpts = inlink->dst->priv;
112 int64_t in_pts = frame->pts;
115 if (isnan(setpts->var_values[VAR_STARTPTS]))
116 setpts->var_values[VAR_STARTPTS] = TS2D(frame->pts);
118 setpts->var_values[VAR_INTERLACED] = frame->interlaced_frame;
119 setpts->var_values[VAR_PTS ] = TS2D(frame->pts);
120 setpts->var_values[VAR_RTCTIME ] = av_gettime();
122 d = av_expr_eval(setpts->expr, setpts->var_values, NULL);
123 frame->pts = D2TS(d);
126 av_log(inlink->dst, AV_LOG_DEBUG,
127 "n:%"PRId64" interlaced:%d pts:%"PRId64" t:%f -> pts:%"PRId64" t:%f\n",
128 (int64_t)setpts->var_values[VAR_N],
129 (int)setpts->var_values[VAR_INTERLACED],
130 in_pts, in_pts * av_q2d(inlink->time_base),
131 frame->pts, frame->pts * av_q2d(inlink->time_base));
135 setpts->var_values[VAR_N] += 1.0;
136 setpts->var_values[VAR_PREV_INPTS ] = TS2D(in_pts);
137 setpts->var_values[VAR_PREV_OUTPTS] = TS2D(frame->pts);
138 return ff_filter_frame(inlink->dst->outputs[0], frame);
141 static av_cold void uninit(AVFilterContext *ctx)
143 SetPTSContext *setpts = ctx->priv;
144 av_expr_free(setpts->expr);
148 static const AVFilterPad avfilter_vf_setpts_inputs[] = {
151 .type = AVMEDIA_TYPE_VIDEO,
152 .get_video_buffer = ff_null_get_video_buffer,
153 .config_props = config_input,
154 .filter_frame = filter_frame,
159 static const AVFilterPad avfilter_vf_setpts_outputs[] = {
162 .type = AVMEDIA_TYPE_VIDEO,
167 AVFilter avfilter_vf_setpts = {
169 .description = NULL_IF_CONFIG_SMALL("Set PTS for the output video frame."),
173 .priv_size = sizeof(SetPTSContext),
175 .inputs = avfilter_vf_setpts_inputs,
176 .outputs = avfilter_vf_setpts_outputs,