78691ea1fcf8974b75125c3fdd9f19a1e0d24370
[ffmpeg.git] / libavfilter / f_settb.c
1 /*
2  * Copyright (c) 2010 Stefano Sabatini
3  *
4  * This file is part of FFmpeg.
5  *
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.
10  *
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.
15  *
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
19  */
20
21 /**
22  * @file
23  * Set timebase for the output link.
24  */
25
26 #include <inttypes.h>
27 #include <stdio.h>
28
29 #include "libavutil/avstring.h"
30 #include "libavutil/eval.h"
31 #include "libavutil/internal.h"
32 #include "libavutil/mathematics.h"
33 #include "libavutil/opt.h"
34 #include "libavutil/rational.h"
35 #include "avfilter.h"
36 #include "internal.h"
37 #include "audio.h"
38 #include "video.h"
39
40 static const char *const var_names[] = {
41     "AVTB",   /* default timebase 1/AV_TIME_BASE */
42     "intb",   /* input timebase */
43     "sr",     /* sample rate */
44     NULL
45 };
46
47 enum var_name {
48     VAR_AVTB,
49     VAR_INTB,
50     VAR_SR,
51     VAR_VARS_NB
52 };
53
54 typedef struct {
55     const AVClass *class;
56     char *tb_expr;
57     double var_values[VAR_VARS_NB];
58 } SetTBContext;
59
60 #define OFFSET(x) offsetof(SetTBContext, x)
61 #define DEFINE_OPTIONS(filt_name, filt_type)                                               \
62 static const AVOption filt_name##_options[] = {                                            \
63     { "expr", "set expression determining the output timebase", OFFSET(tb_expr), AV_OPT_TYPE_STRING, {.str="intb"}, \
64            .flags=AV_OPT_FLAG_##filt_type##_PARAM|AV_OPT_FLAG_FILTERING_PARAM },           \
65     { "tb",   "set expression determining the output timebase", OFFSET(tb_expr), AV_OPT_TYPE_STRING, {.str="intb"}, \
66            .flags=AV_OPT_FLAG_##filt_type##_PARAM|AV_OPT_FLAG_FILTERING_PARAM },           \
67     { NULL }                                                                               \
68 }
69
70 static int config_output_props(AVFilterLink *outlink)
71 {
72     AVFilterContext *ctx = outlink->src;
73     SetTBContext *settb = ctx->priv;
74     AVFilterLink *inlink = ctx->inputs[0];
75     AVRational time_base;
76     int ret;
77     double res;
78
79     settb->var_values[VAR_AVTB] = av_q2d(AV_TIME_BASE_Q);
80     settb->var_values[VAR_INTB] = av_q2d(inlink->time_base);
81     settb->var_values[VAR_SR]   = inlink->sample_rate;
82
83     outlink->w = inlink->w;
84     outlink->h = inlink->h;
85
86     if ((ret = av_expr_parse_and_eval(&res, settb->tb_expr, var_names, settb->var_values,
87                                       NULL, NULL, NULL, NULL, NULL, 0, NULL)) < 0) {
88         av_log(ctx, AV_LOG_ERROR, "Invalid expression '%s' for timebase.\n", settb->tb_expr);
89         return ret;
90     }
91     time_base = av_d2q(res, INT_MAX);
92     if (time_base.num <= 0 || time_base.den <= 0) {
93         av_log(ctx, AV_LOG_ERROR,
94                "Invalid non-positive values for the timebase num:%d or den:%d.\n",
95                time_base.num, time_base.den);
96         return AVERROR(EINVAL);
97     }
98
99     outlink->time_base = time_base;
100     av_log(outlink->src, AV_LOG_VERBOSE, "tb:%d/%d -> tb:%d/%d\n",
101            inlink ->time_base.num, inlink ->time_base.den,
102            outlink->time_base.num, outlink->time_base.den);
103
104     return 0;
105 }
106
107 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
108 {
109     AVFilterContext *ctx = inlink->dst;
110     AVFilterLink *outlink = ctx->outputs[0];
111
112     if (av_cmp_q(inlink->time_base, outlink->time_base)) {
113         int64_t orig_pts = frame->pts;
114         frame->pts = av_rescale_q(frame->pts, inlink->time_base, outlink->time_base);
115         av_log(ctx, AV_LOG_DEBUG, "tb:%d/%d pts:%"PRId64" -> tb:%d/%d pts:%"PRId64"\n",
116                inlink ->time_base.num, inlink ->time_base.den, orig_pts,
117                outlink->time_base.num, outlink->time_base.den, frame->pts);
118     }
119
120     return ff_filter_frame(outlink, frame);
121 }
122
123 #if CONFIG_SETTB_FILTER
124
125 DEFINE_OPTIONS(settb, VIDEO);
126 AVFILTER_DEFINE_CLASS(settb);
127
128 static const AVFilterPad avfilter_vf_settb_inputs[] = {
129     {
130         .name             = "default",
131         .type             = AVMEDIA_TYPE_VIDEO,
132         .filter_frame     = filter_frame,
133     },
134     { NULL }
135 };
136
137 static const AVFilterPad avfilter_vf_settb_outputs[] = {
138     {
139         .name         = "default",
140         .type         = AVMEDIA_TYPE_VIDEO,
141         .config_props = config_output_props,
142     },
143     { NULL }
144 };
145
146 AVFilter avfilter_vf_settb = {
147     .name      = "settb",
148     .description = NULL_IF_CONFIG_SMALL("Set timebase for the video output link."),
149
150     .priv_size = sizeof(SetTBContext),
151     .priv_class = &settb_class,
152
153     .inputs    = avfilter_vf_settb_inputs,
154     .outputs   = avfilter_vf_settb_outputs,
155 };
156 #endif
157
158 #if CONFIG_ASETTB_FILTER
159
160 DEFINE_OPTIONS(asettb, AUDIO);
161 AVFILTER_DEFINE_CLASS(asettb);
162
163 static const AVFilterPad avfilter_af_asettb_inputs[] = {
164     {
165         .name             = "default",
166         .type             = AVMEDIA_TYPE_AUDIO,
167         .filter_frame     = filter_frame,
168     },
169     { NULL }
170 };
171
172 static const AVFilterPad avfilter_af_asettb_outputs[] = {
173     {
174         .name         = "default",
175         .type         = AVMEDIA_TYPE_AUDIO,
176         .config_props = config_output_props,
177     },
178     { NULL }
179 };
180
181 AVFilter avfilter_af_asettb = {
182     .name      = "asettb",
183     .description = NULL_IF_CONFIG_SMALL("Set timebase for the audio output link."),
184
185     .priv_size = sizeof(SetTBContext),
186     .inputs    = avfilter_af_asettb_inputs,
187     .outputs   = avfilter_af_asettb_outputs,
188     .priv_class = &asettb_class,
189 };
190 #endif