mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-02 03:06:28 +02:00
153 lines
5.4 KiB
C
153 lines
5.4 KiB
C
/*
|
|
* Copyright (c) 2023 Paul B Mahol
|
|
*
|
|
* 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/avassert.h"
|
|
#include "libavutil/channel_layout.h"
|
|
#include "libavutil/opt.h"
|
|
|
|
#include "audio.h"
|
|
#include "avfilter.h"
|
|
#include "filters.h"
|
|
#include "formats.h"
|
|
#include "internal.h"
|
|
|
|
typedef struct AFDelaySrcContext {
|
|
const AVClass *class;
|
|
|
|
double delay;
|
|
int sample_rate;
|
|
int nb_samples;
|
|
int nb_taps;
|
|
AVChannelLayout chlayout;
|
|
|
|
int64_t pts;
|
|
} AFDelaySrcContext;
|
|
|
|
static float sincf(float x)
|
|
{
|
|
if (x == 0.f)
|
|
return 1.f;
|
|
return sinf(M_PI * x) / (M_PI * x);
|
|
}
|
|
|
|
static int activate(AVFilterContext *ctx)
|
|
{
|
|
AVFilterLink *outlink = ctx->outputs[0];
|
|
AFDelaySrcContext *s = ctx->priv;
|
|
AVFrame *frame = NULL;
|
|
int nb_samples;
|
|
float *dst;
|
|
|
|
if (!ff_outlink_frame_wanted(outlink))
|
|
return FFERROR_NOT_READY;
|
|
|
|
nb_samples = FFMIN(s->nb_samples, s->nb_taps - s->pts);
|
|
if (nb_samples <= 0) {
|
|
ff_outlink_set_status(outlink, AVERROR_EOF, s->pts);
|
|
return 0;
|
|
}
|
|
|
|
if (!(frame = ff_get_audio_buffer(outlink, nb_samples)))
|
|
return AVERROR(ENOMEM);
|
|
|
|
dst = (float *)frame->extended_data[0];
|
|
for (int n = 0; n < nb_samples; n++) {
|
|
float x = s->pts + n;
|
|
dst[n] = sincf(x - s->delay) * cosf(M_PI * (x - s->delay) / s->nb_taps) / sincf((x - s->delay) / s->nb_taps);
|
|
}
|
|
|
|
for (int ch = 1; ch < frame->ch_layout.nb_channels; ch++)
|
|
memcpy(frame->extended_data[ch], dst, sizeof(*dst) * nb_samples);
|
|
|
|
frame->pts = s->pts;
|
|
s->pts += nb_samples;
|
|
|
|
return ff_filter_frame(outlink, frame);
|
|
}
|
|
|
|
static int query_formats(AVFilterContext *ctx)
|
|
{
|
|
AFDelaySrcContext *s = ctx->priv;
|
|
AVChannelLayout chlayouts[] = { s->chlayout, { 0 } };
|
|
int sample_rates[] = { s->sample_rate, -1 };
|
|
static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLTP,
|
|
AV_SAMPLE_FMT_NONE };
|
|
int ret = ff_set_common_formats_from_list(ctx, sample_fmts);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = ff_set_common_channel_layouts_from_list(ctx, chlayouts);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
return ff_set_common_samplerates_from_list(ctx, sample_rates);
|
|
}
|
|
|
|
static int config_output(AVFilterLink *outlink)
|
|
{
|
|
AVFilterContext *ctx = outlink->src;
|
|
AFDelaySrcContext *s = ctx->priv;
|
|
|
|
outlink->sample_rate = s->sample_rate;
|
|
s->pts = 0;
|
|
if (s->nb_taps <= 0)
|
|
s->nb_taps = s->delay * 8 + 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const AVFilterPad afdelaysrc_outputs[] = {
|
|
{
|
|
.name = "default",
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
|
.config_props = config_output,
|
|
},
|
|
};
|
|
|
|
#define AF AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
|
|
#define OFFSET(x) offsetof(AFDelaySrcContext, x)
|
|
|
|
static const AVOption afdelaysrc_options[] = {
|
|
{ "delay", "set fractional delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE,{.dbl=0}, 0, INT16_MAX, AF },
|
|
{ "d", "set fractional delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE,{.dbl=0}, 0, INT16_MAX, AF },
|
|
{ "sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64=44100}, 1, INT_MAX, AF },
|
|
{ "r", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64=44100}, 1, INT_MAX, AF },
|
|
{ "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, AF },
|
|
{ "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, AF },
|
|
{ "taps", "set number of taps for delay filter", OFFSET(nb_taps), AV_OPT_TYPE_INT, {.i64=0}, 0, 32768, AF },
|
|
{ "t", "set number of taps for delay filter", OFFSET(nb_taps), AV_OPT_TYPE_INT, {.i64=0}, 0, 32768, AF },
|
|
{ "channel_layout", "set channel layout", OFFSET(chlayout), AV_OPT_TYPE_CHLAYOUT,{.str="stereo"},0, 0, AF },
|
|
{ "c", "set channel layout", OFFSET(chlayout), AV_OPT_TYPE_CHLAYOUT,{.str="stereo"},0, 0, AF },
|
|
{ NULL }
|
|
};
|
|
|
|
AVFILTER_DEFINE_CLASS(afdelaysrc);
|
|
|
|
const AVFilter ff_asrc_afdelaysrc = {
|
|
.name = "afdelaysrc",
|
|
.description = NULL_IF_CONFIG_SMALL("Generate a Fractional delay FIR coefficients."),
|
|
.priv_size = sizeof(AFDelaySrcContext),
|
|
.priv_class = &afdelaysrc_class,
|
|
.activate = activate,
|
|
.inputs = NULL,
|
|
FILTER_OUTPUTS(afdelaysrc_outputs),
|
|
FILTER_QUERY_FUNC(query_formats),
|
|
};
|