FFmpeg/libavfilter/af_crystalizer.c
Vitaly Ostrosablin 90ddcaaf2d avfilter: add crystalizer audio filter
Signed-off-by: Vitaly Ostrosablin <tmp6154@yandex.ru>
2016-08-07 10:58:42 +02:00

154 lines
4.1 KiB
C

/*
* Copyright (c) 2016 The FFmpeg Project
*
* 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/channel_layout.h"
#include "libavutil/opt.h"
#include "avfilter.h"
#include "audio.h"
#include "formats.h"
typedef struct CrystalizerContext {
const AVClass *class;
float mult;
int clip;
AVFrame *prev;
} CrystalizerContext;
#define OFFSET(x) offsetof(CrystalizerContext, x)
#define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption crystalizer_options[] = {
{ "i", "set intensity", OFFSET(mult), AV_OPT_TYPE_FLOAT, {.dbl=2.0}, 0, 10, A },
{ "c", "enable clipping", OFFSET(clip), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, A },
{ NULL }
};
AVFILTER_DEFINE_CLASS(crystalizer);
static int query_formats(AVFilterContext *ctx)
{
AVFilterFormats *formats = NULL;
AVFilterChannelLayouts *layouts = NULL;
int ret;
if ((ret = ff_add_format (&formats, AV_SAMPLE_FMT_FLT )) < 0 ||
(ret = ff_set_common_formats(ctx , formats )) < 0)
return ret;
layouts = ff_all_channel_counts();
if (!layouts)
return AVERROR(ENOMEM);
ret = ff_set_common_channel_layouts(ctx, layouts);
if (ret < 0)
return ret;
formats = ff_all_samplerates();
return ff_set_common_samplerates(ctx, formats);
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
CrystalizerContext *s = ctx->priv;
const float *src = (const float *)in->data[0];
const float mult = s->mult;
AVFrame *out;
float *dst, *prv;
int n, c;
if (!s->prev) {
s->prev = ff_get_audio_buffer(inlink, 1);
if (!s->prev) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
}
if (av_frame_is_writable(in)) {
out = in;
} else {
out = ff_get_audio_buffer(inlink, in->nb_samples);
if (!out) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, in);
}
dst = (float *)out->data[0];
prv = (float *)s->prev->data[0];
for (n = 0; n < in->nb_samples; n++) {
for (c = 0; c < in->channels; c++) {
float current = src[c];
dst[c] = current + (current - prv[c]) * mult;
prv[c] = current;
if (s->clip) {
dst[c] = av_clipf(dst[c], -1, 1);
}
}
dst += c;
src += c;
}
if (out != in)
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
static av_cold void uninit(AVFilterContext *ctx)
{
CrystalizerContext *s = ctx->priv;
av_frame_free(&s->prev);
}
static const AVFilterPad inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
},
{ NULL }
};
AVFilter ff_af_crystalizer = {
.name = "crystalizer",
.description = NULL_IF_CONFIG_SMALL("Simple expand audio dynamic range filter."),
.query_formats = query_formats,
.priv_size = sizeof(CrystalizerContext),
.priv_class = &crystalizer_class,
.uninit = uninit,
.inputs = inputs,
.outputs = outputs,
};