libavfilter/af_aformat.c

   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
  21 /**
  22  * @file
  23  * format audio filter
  24  */
  25
  26 #include "libavutil/avstring.h"
  27 #include "libavutil/channel_layout.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
  39     AVFilterFormats *formats;
  40     AVFilterFormats *sample_rates;
  41     AVFilterChannelLayouts *channel_layouts;
  42
  43     char *formats_str;
  44     char *sample_rates_str;
  45     char *channel_layouts_str;
  46 } AFormatContext;
  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;
 101     av_opt_set_defaults(s);
 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
 108     PARSE_FORMATS(s->formats_str, enum AVSampleFormat, s->formats,
 109                   ff_add_format, av_get_sample_fmt, AV_SAMPLE_FMT_NONE, "sample format");
 110     PARSE_FORMATS(s->sample_rates_str, int, s->sample_rates, ff_add_format,
 111                   get_sample_rate, 0, "sample rate");
 112     PARSE_FORMATS(s->channel_layouts_str, uint64_t, s->channel_layouts,
 113                   ff_add_channel_layout, av_get_channel_layout, 0,
 114                   "channel layout");
 115
 116 fail:
 117     av_opt_free(s);
 118     return ret;
 119 }
 120
 121 static int query_formats(AVFilterContext *ctx)
 122 {
 123     AFormatContext *s = ctx->priv;
 124
 125     ff_set_common_formats(ctx, s->formats ? s->formats :
 126                                                   ff_all_formats(AVMEDIA_TYPE_AUDIO));
 127     ff_set_common_samplerates(ctx, s->sample_rates ? s->sample_rates :
 128                                                      ff_all_samplerates());
 129     ff_set_common_channel_layouts(ctx, s->channel_layouts ? s->channel_layouts :
 130                                                             ff_all_channel_layouts());
 131
 132     return 0;
 133 }
 134
 135 static const AVFilterPad avfilter_af_aformat_inputs[] = {
 136     {
 137         .name = "default",
 138         .type = AVMEDIA_TYPE_AUDIO,
 139     },
 140     { NULL }
 141 };
 142
 143 static const AVFilterPad avfilter_af_aformat_outputs[] = {
 144     {
 145         .name = "default",
 146         .type = AVMEDIA_TYPE_AUDIO
 147     },
 148     { NULL }
 149 };
 150
 151 AVFilter avfilter_af_aformat = {
 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 };