0,0 → 1,119 |
/* |
* Copyright (c) 2013 Nicolas George |
* |
* This file is part of FFmpeg. |
* |
* FFmpeg 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. |
* |
* FFmpeg 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 FFmpeg; if not, write to the Free Software Foundation, Inc., |
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
*/ |
|
#include "libavutil/opt.h" |
#include "avfilter.h" |
#include "internal.h" |
|
typedef struct { |
const AVClass *class; |
int sample_rate; |
int rescale_pts; |
} ASetRateContext; |
|
#define CONTEXT ASetRateContext |
#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM |
|
#define OPT_GENERIC(name, field, def, min, max, descr, type, deffield, ...) \ |
{ name, descr, offsetof(CONTEXT, field), AV_OPT_TYPE_ ## type, \ |
{ .deffield = def }, min, max, FLAGS, __VA_ARGS__ } |
|
#define OPT_INT(name, field, def, min, max, descr, ...) \ |
OPT_GENERIC(name, field, def, min, max, descr, INT, i64, __VA_ARGS__) |
|
static const AVOption asetrate_options[] = { |
OPT_INT("sample_rate", sample_rate, 44100, 1, INT_MAX, "set the sample rate"), |
OPT_INT("r", sample_rate, 44100, 1, INT_MAX, "set the sample rate"), |
{NULL}, |
}; |
|
AVFILTER_DEFINE_CLASS(asetrate); |
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static av_cold int query_formats(AVFilterContext *ctx) |
{ |
ASetRateContext *sr = ctx->priv; |
int sample_rates[] = { sr->sample_rate, -1 }; |
|
ff_formats_ref(ff_make_format_list(sample_rates), |
&ctx->outputs[0]->in_samplerates); |
return 0; |
} |
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static av_cold int config_props(AVFilterLink *outlink) |
{ |
AVFilterContext *ctx = outlink->src; |
ASetRateContext *sr = ctx->priv; |
AVFilterLink *inlink = ctx->inputs[0]; |
AVRational intb = ctx->inputs[0]->time_base; |
int inrate = inlink->sample_rate; |
|
if (intb.num == 1 && intb.den == inrate) { |
outlink->time_base.num = 1; |
outlink->time_base.den = outlink->sample_rate; |
} else { |
outlink->time_base = intb; |
sr->rescale_pts = 1; |
if (av_q2d(intb) > 1.0 / FFMAX(inrate, outlink->sample_rate)) |
av_log(ctx, AV_LOG_WARNING, "Time base is inaccurate\n"); |
} |
return 0; |
} |
|
static int filter_frame(AVFilterLink *inlink, AVFrame *frame) |
{ |
AVFilterContext *ctx = inlink->dst; |
ASetRateContext *sr = ctx->priv; |
AVFilterLink *outlink = ctx->outputs[0]; |
|
frame->sample_rate = outlink->sample_rate; |
if (sr->rescale_pts) |
frame->pts = av_rescale(frame->pts, inlink->sample_rate, |
outlink->sample_rate); |
return ff_filter_frame(outlink, frame); |
} |
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static const AVFilterPad asetrate_inputs[] = { |
{ |
.name = "default", |
.type = AVMEDIA_TYPE_AUDIO, |
.filter_frame = filter_frame, |
}, |
{ NULL } |
}; |
|
static const AVFilterPad asetrate_outputs[] = { |
{ |
.name = "default", |
.type = AVMEDIA_TYPE_AUDIO, |
.config_props = config_props, |
}, |
{ NULL } |
}; |
|
AVFilter avfilter_af_asetrate = { |
.name = "asetrate", |
.description = NULL_IF_CONFIG_SMALL("Change the sample rate without " |
"altering the data."), |
.query_formats = query_formats, |
.priv_size = sizeof(ASetRateContext), |
.inputs = asetrate_inputs, |
.outputs = asetrate_outputs, |
.priv_class = &asetrate_class, |
}; |