/* * Copyright (c) 2011 Mina Nagy Zaki * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * format audio filter */ #include "libavutil/audioconvert.h"#include "libavutil/avstring.h"#include "libavutil/opt.h" #include "audio.h"#include "avfilter.h"#include "formats.h"#include "internal.h" typedef struct AFormatContext {    const AVClass   *class;     AVFilterFormats *formats;    AVFilterFormats *sample_rates;    AVFilterChannelLayouts *channel_layouts;     char *formats_str;    char *sample_rates_str;    char *channel_layouts_str;} AFormatContext; #define OFFSET(x) offsetof(AFormatContext, x)#define A AV_OPT_FLAG_AUDIO_PARAMstatic const AVOption options[] = {    { "sample_fmts",     "A comma-separated list of sample formats.",  OFFSET(formats_str),         AV_OPT_TYPE_STRING, .flags = A },    { "sample_rates",    "A comma-separated list of sample rates.",    OFFSET(sample_rates_str),    AV_OPT_TYPE_STRING, .flags = A },    { "channel_layouts", "A comma-separated list of channel layouts.", OFFSET(channel_layouts_str), AV_OPT_TYPE_STRING, .flags = A },    { NULL },}; static const AVClass aformat_class = {    .class_name = "aformat filter",    .item_name  = av_default_item_name,    .option     = options,    .version    = LIBAVUTIL_VERSION_INT,}; #define PARSE_FORMATS(str, type, list, add_to_list, get_fmt, none, desc)    \do {                                                                        \    char *next, *cur = str;                                                 \    while (cur) {                                                           \        type fmt;                                                           \        next = strchr(cur, ',');                                            \        if (next)                                                           \            *next++ = 0;                                                    \                                                                            \        if ((fmt = get_fmt(cur)) == none) {                                 \            av_log(ctx, AV_LOG_ERROR, "Error parsing " desc ": %s.\n", cur);\            ret = AVERROR(EINVAL);                                          \            goto fail;                                                      \        }                                                                   \        add_to_list(&list, fmt);                                            \                                                                            \        cur = next;                                                         \    }                                                                       \} while (0) static int get_sample_rate(const char *samplerate){    int ret = strtol(samplerate, NULL, 0);    return FFMAX(ret, 0);} static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque){    AFormatContext *s = ctx->priv;    int ret;     if (!args) {        av_log(ctx, AV_LOG_ERROR, "No parameters supplied.\n");        return AVERROR(EINVAL);    }     s->class = &aformat_class;    av_opt_set_defaults(s);     if ((ret = av_set_options_string(s, args, "=", ":")) < 0) {        av_log(ctx, AV_LOG_ERROR, "Error parsing options string '%s'.\n", args);        return ret;    }     PARSE_FORMATS(s->formats_str, enum AVSampleFormat, s->formats,                  ff_add_format, av_get_sample_fmt, AV_SAMPLE_FMT_NONE, "sample format");    PARSE_FORMATS(s->sample_rates_str, int, s->sample_rates, ff_add_format,                  get_sample_rate, 0, "sample rate");    PARSE_FORMATS(s->channel_layouts_str, uint64_t, s->channel_layouts,                  ff_add_channel_layout, av_get_channel_layout, 0,                  "channel layout"); fail:    av_opt_free(s);    return ret;} static int query_formats(AVFilterContext *ctx){    AFormatContext *s = ctx->priv;     ff_set_common_formats(ctx, s->formats ? s->formats :                                                  ff_all_formats(AVMEDIA_TYPE_AUDIO));    ff_set_common_samplerates(ctx, s->sample_rates ? s->sample_rates :                                                     ff_all_samplerates());    ff_set_common_channel_layouts(ctx, s->channel_layouts ? s->channel_layouts :                                                            ff_all_channel_layouts());     return 0;} AVFilter avfilter_af_aformat = {    .name          = "aformat",    .description   = NULL_IF_CONFIG_SMALL("Convert the input audio to one of the specified formats."),    .init          = init,    .query_formats = query_formats,    .priv_size     = sizeof(AFormatContext),     .inputs        = (AVFilterPad[]) {{ .name            = "default",                                        .type            = AVMEDIA_TYPE_AUDIO,                                        .filter_samples  = ff_null_filter_samples },                                      { .name = NULL}},    .outputs       = (AVFilterPad[]) {{ .name            = "default",                                        .type            = AVMEDIA_TYPE_AUDIO},                                      { .name = NULL}},};