2 * Copyright (c) 2013 Nicolas George
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 License
8 * 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
14 * GNU Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public License
17 * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "libavutil/opt.h"
31 #define CONTEXT ASetRateContext
32 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
34 #define OPT_GENERIC(name, field, def, min, max, descr, type, deffield, ...) \
35 { name, descr, offsetof(CONTEXT, field), AV_OPT_TYPE_ ## type, \
36 { .deffield = def }, min, max, FLAGS, __VA_ARGS__ }
38 #define OPT_INT(name, field, def, min, max, descr, ...) \
39 OPT_GENERIC(name, field, def, min, max, descr, INT, i64, __VA_ARGS__)
41 static const AVOption asetrate_options
[] = {
42 OPT_INT("sample_rate", sample_rate
, 44100, 1, INT_MAX
, "set the sample rate"),
43 OPT_INT("r", sample_rate
, 44100, 1, INT_MAX
, "set the sample rate"),
47 AVFILTER_DEFINE_CLASS(asetrate
);
49 static av_cold
int query_formats(AVFilterContext
*ctx
)
51 ASetRateContext
*sr
= ctx
->priv
;
52 int sample_rates
[] = { sr
->sample_rate
, -1 };
54 ff_formats_ref(ff_make_format_list(sample_rates
),
55 &ctx
->outputs
[0]->in_samplerates
);
59 static av_cold
int config_props(AVFilterLink
*outlink
)
61 AVFilterContext
*ctx
= outlink
->src
;
62 ASetRateContext
*sr
= ctx
->priv
;
63 AVFilterLink
*inlink
= ctx
->inputs
[0];
64 AVRational intb
= ctx
->inputs
[0]->time_base
;
65 int inrate
= inlink
->sample_rate
;
67 if (intb
.num
== 1 && intb
.den
== inrate
) {
68 outlink
->time_base
.num
= 1;
69 outlink
->time_base
.den
= outlink
->sample_rate
;
71 outlink
->time_base
= intb
;
73 if (av_q2d(intb
) > 1.0 / FFMAX(inrate
, outlink
->sample_rate
))
74 av_log(ctx
, AV_LOG_WARNING
, "Time base is inaccurate\n");
79 static int filter_frame(AVFilterLink
*inlink
, AVFrame
*frame
)
81 AVFilterContext
*ctx
= inlink
->dst
;
82 ASetRateContext
*sr
= ctx
->priv
;
83 AVFilterLink
*outlink
= ctx
->outputs
[0];
85 frame
->sample_rate
= outlink
->sample_rate
;
87 frame
->pts
= av_rescale(frame
->pts
, inlink
->sample_rate
,
88 outlink
->sample_rate
);
89 return ff_filter_frame(outlink
, frame
);
92 static const AVFilterPad asetrate_inputs
[] = {
95 .type
= AVMEDIA_TYPE_AUDIO
,
96 .filter_frame
= filter_frame
,
101 static const AVFilterPad asetrate_outputs
[] = {
104 .type
= AVMEDIA_TYPE_AUDIO
,
105 .config_props
= config_props
,
110 AVFilter ff_af_asetrate
= {
112 .description
= NULL_IF_CONFIG_SMALL("Change the sample rate without "
113 "altering the data."),
114 .query_formats
= query_formats
,
115 .priv_size
= sizeof(ASetRateContext
),
116 .inputs
= asetrate_inputs
,
117 .outputs
= asetrate_outputs
,
118 .priv_class
= &asetrate_class
,