af_aformat.c
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1 /*
2  * Copyright (c) 2011 Mina Nagy Zaki
3  *
4  * This file is part of Libav.
5  *
6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
26 #include "libavutil/avstring.h"
28 #include "libavutil/common.h"
29 #include "libavutil/opt.h"
30 
31 #include "audio.h"
32 #include "avfilter.h"
33 #include "formats.h"
34 #include "internal.h"
35 
36 typedef struct AFormatContext {
37  const AVClass *class;
38 
42 
43  char *formats_str;
47 
48 #define OFFSET(x) offsetof(AFormatContext, x)
49 #define A AV_OPT_FLAG_AUDIO_PARAM
50 static const AVOption options[] = {
51  { "sample_fmts", "A comma-separated list of sample formats.", OFFSET(formats_str), AV_OPT_TYPE_STRING, .flags = A },
52  { "sample_rates", "A comma-separated list of sample rates.", OFFSET(sample_rates_str), AV_OPT_TYPE_STRING, .flags = A },
53  { "channel_layouts", "A comma-separated list of channel layouts.", OFFSET(channel_layouts_str), AV_OPT_TYPE_STRING, .flags = A },
54  { NULL },
55 };
56 
57 static const AVClass aformat_class = {
58  .class_name = "aformat filter",
59  .item_name = av_default_item_name,
60  .option = options,
61  .version = LIBAVUTIL_VERSION_INT,
62 };
63 
64 #define PARSE_FORMATS(str, type, list, add_to_list, get_fmt, none, desc) \
65 do { \
66  char *next, *cur = str; \
67  while (cur) { \
68  type fmt; \
69  next = strchr(cur, ','); \
70  if (next) \
71  *next++ = 0; \
72  \
73  if ((fmt = get_fmt(cur)) == none) { \
74  av_log(ctx, AV_LOG_ERROR, "Error parsing " desc ": %s.\n", cur);\
75  ret = AVERROR(EINVAL); \
76  goto fail; \
77  } \
78  add_to_list(&list, fmt); \
79  \
80  cur = next; \
81  } \
82 } while (0)
83 
84 static int get_sample_rate(const char *samplerate)
85 {
86  int ret = strtol(samplerate, NULL, 0);
87  return FFMAX(ret, 0);
88 }
89 
90 static av_cold int init(AVFilterContext *ctx, const char *args)
91 {
92  AFormatContext *s = ctx->priv;
93  int ret;
94 
95  if (!args) {
96  av_log(ctx, AV_LOG_ERROR, "No parameters supplied.\n");
97  return AVERROR(EINVAL);
98  }
99 
100  s->class = &aformat_class;
102 
103  if ((ret = av_set_options_string(s, args, "=", ":")) < 0) {
104  av_log(ctx, AV_LOG_ERROR, "Error parsing options string '%s'.\n", args);
105  return ret;
106  }
107 
111  get_sample_rate, 0, "sample rate");
114  "channel layout");
115 
116 fail:
117  av_opt_free(s);
118  return ret;
119 }
120 
122 {
123  AFormatContext *s = ctx->priv;
124 
125  ff_set_common_formats(ctx, s->formats ? s->formats :
131 
132  return 0;
133 }
134 
136  {
137  .name = "default",
138  .type = AVMEDIA_TYPE_AUDIO,
139  },
140  { NULL }
141 };
142 
144  {
145  .name = "default",
146  .type = AVMEDIA_TYPE_AUDIO
147  },
148  { NULL }
149 };
150 
152  .name = "aformat",
153  .description = NULL_IF_CONFIG_SMALL("Convert the input audio to one of the specified formats."),
154  .init = init,
155  .query_formats = query_formats,
156  .priv_size = sizeof(AFormatContext),
157 
158  .inputs = avfilter_af_aformat_inputs,
159  .outputs = avfilter_af_aformat_outputs,
160 };