2 * Copyright (c) 2010 Stefano Sabatini
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * Set timebase for the output link.
26 #include "libavutil/avstring.h"
27 #include "libavutil/eval.h"
28 #include "libavutil/mathematics.h"
29 #include "libavutil/rational.h"
35 static const char *const var_names[] = {
36 "AVTB", /* default timebase 1/AV_TIME_BASE */
37 "intb", /* input timebase */
38 "sr", /* sample rate */
51 double var_values[VAR_VARS_NB];
54 static av_cold int init(AVFilterContext *ctx, const char *args)
56 SetTBContext *settb = ctx->priv;
57 av_strlcpy(settb->tb_expr, "intb", sizeof(settb->tb_expr));
60 sscanf(args, "%255[^:]", settb->tb_expr);
65 static int config_output_props(AVFilterLink *outlink)
67 AVFilterContext *ctx = outlink->src;
68 SetTBContext *settb = ctx->priv;
69 AVFilterLink *inlink = ctx->inputs[0];
74 settb->var_values[VAR_AVTB] = av_q2d(AV_TIME_BASE_Q);
75 settb->var_values[VAR_INTB] = av_q2d(inlink->time_base);
76 settb->var_values[VAR_SR] = inlink->sample_rate;
78 outlink->w = inlink->w;
79 outlink->h = inlink->h;
81 if ((ret = av_expr_parse_and_eval(&res, settb->tb_expr, var_names, settb->var_values,
82 NULL, NULL, NULL, NULL, NULL, 0, NULL)) < 0) {
83 av_log(ctx, AV_LOG_ERROR, "Invalid expression '%s' for timebase.\n", settb->tb_expr);
86 time_base = av_d2q(res, INT_MAX);
87 if (time_base.num <= 0 || time_base.den <= 0) {
88 av_log(ctx, AV_LOG_ERROR,
89 "Invalid non-positive values for the timebase num:%d or den:%d.\n",
90 time_base.num, time_base.den);
91 return AVERROR(EINVAL);
94 outlink->time_base = time_base;
95 av_log(outlink->src, AV_LOG_VERBOSE, "tb:%d/%d -> tb:%d/%d\n",
96 inlink ->time_base.num, inlink ->time_base.den,
97 outlink->time_base.num, outlink->time_base.den);
102 static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
104 AVFilterContext *ctx = inlink->dst;
105 AVFilterLink *outlink = ctx->outputs[0];
107 if (av_cmp_q(inlink->time_base, outlink->time_base)) {
108 int64_t orig_pts = picref->pts;
109 picref->pts = av_rescale_q(picref->pts, inlink->time_base, outlink->time_base);
110 av_log(ctx, AV_LOG_DEBUG, "tb:%d/%d pts:%"PRId64" -> tb:%d/%d pts:%"PRId64"\n",
111 inlink ->time_base.num, inlink ->time_base.den, orig_pts,
112 outlink->time_base.num, outlink->time_base.den, picref->pts);
114 inlink->cur_buf = NULL;
116 ff_start_frame(outlink, picref);
119 static int filter_samples(AVFilterLink *inlink, AVFilterBufferRef *insamples)
121 AVFilterContext *ctx = inlink->dst;
122 AVFilterLink *outlink = ctx->outputs[0];
123 AVFilterBufferRef *outsamples = insamples;
125 if (av_cmp_q(inlink->time_base, outlink->time_base)) {
126 outsamples = avfilter_ref_buffer(insamples, ~0);
127 outsamples->pts = av_rescale_q(insamples->pts, inlink->time_base, outlink->time_base);
128 av_log(ctx, AV_LOG_DEBUG, "tb:%d/%d pts:%"PRId64" -> tb:%d/%d pts:%"PRId64"\n",
129 inlink ->time_base.num, inlink ->time_base.den, insamples ->pts,
130 outlink->time_base.num, outlink->time_base.den, outsamples->pts);
131 avfilter_unref_buffer(insamples);
134 return ff_filter_samples(outlink, outsamples);
137 #if CONFIG_SETTB_FILTER
138 AVFilter avfilter_vf_settb = {
140 .description = NULL_IF_CONFIG_SMALL("Set timebase for the video output link."),
143 .priv_size = sizeof(SetTBContext),
145 .inputs = (const AVFilterPad[]) {
147 .type = AVMEDIA_TYPE_VIDEO,
148 .get_video_buffer = ff_null_get_video_buffer,
149 .start_frame = start_frame,
150 .end_frame = ff_null_end_frame },
153 .outputs = (const AVFilterPad[]) {
155 .type = AVMEDIA_TYPE_VIDEO,
156 .config_props = config_output_props, },
162 #if CONFIG_ASETTB_FILTER
163 AVFilter avfilter_af_asettb = {
165 .description = NULL_IF_CONFIG_SMALL("Set timebase for the audio output link."),
168 .priv_size = sizeof(SetTBContext),
170 .inputs = (const AVFilterPad[]) {
172 .type = AVMEDIA_TYPE_AUDIO,
173 .get_audio_buffer = ff_null_get_audio_buffer,
174 .filter_samples = filter_samples, },
177 .outputs = (const AVFilterPad[]) {
179 .type = AVMEDIA_TYPE_AUDIO,
180 .config_props = config_output_props, },