1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
/*
* 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/ffmath.h"
#include "libavutil/opt.h"
#include "avfilter.h"
#include "audio.h"
#include "filters.h"
typedef struct AudioDynamicSmoothContext {
const AVClass *class;
double sensitivity;
double basefreq;
AVFrame *coeffs;
} AudioDynamicSmoothContext;
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
AudioDynamicSmoothContext *s = ctx->priv;
s->coeffs = ff_get_audio_buffer(inlink, 3);
if (!s->coeffs)
return AVERROR(ENOMEM);
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
AudioDynamicSmoothContext *s = ctx->priv;
const double sensitivity = s->sensitivity;
const double wc = s->basefreq / in->sample_rate;
AVFrame *out;
if (av_frame_is_writable(in)) {
out = in;
} else {
out = ff_get_audio_buffer(outlink, in->nb_samples);
if (!out) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, in);
}
for (int ch = 0; ch < out->ch_layout.nb_channels; ch++) {
const double *src = (const double *)in->extended_data[ch];
double *dst = (double *)out->extended_data[ch];
double *coeffs = (double *)s->coeffs->extended_data[ch];
double low1 = coeffs[0];
double low2 = coeffs[1];
double inz = coeffs[2];
for (int n = 0; n < out->nb_samples; n++) {
double low1z = low1;
double low2z = low2;
double bandz = low2z - low1z;
double wd = wc + sensitivity * fabs(bandz);
double g = fmin(1., wd * (5.9948827 + wd * (-11.969296 + wd * 15.959062)));
low1 = low1z + g * (0.5 * (src[n] + inz) - low1z);
low2 = low2z + g * (0.5 * (low1 + low1z) - low2z);
inz = src[n];
dst[n] = ctx->is_disabled ? src[n] : low2;
}
coeffs[0] = low1;
coeffs[1] = low2;
coeffs[2] = inz;
}
if (out != in)
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
static av_cold void uninit(AVFilterContext *ctx)
{
AudioDynamicSmoothContext *s = ctx->priv;
av_frame_free(&s->coeffs);
}
#define OFFSET(x) offsetof(AudioDynamicSmoothContext, x)
#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
static const AVOption adynamicsmooth_options[] = {
{ "sensitivity", "set smooth sensitivity", OFFSET(sensitivity), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, 1000000, FLAGS },
{ "basefreq", "set base frequency", OFFSET(basefreq), AV_OPT_TYPE_DOUBLE, {.dbl=22050}, 2, 1000000, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(adynamicsmooth);
static const AVFilterPad inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.filter_frame = filter_frame,
.config_props = config_input,
},
};
const AVFilter ff_af_adynamicsmooth = {
.name = "adynamicsmooth",
.description = NULL_IF_CONFIG_SMALL("Apply Dynamic Smoothing of input audio."),
.priv_size = sizeof(AudioDynamicSmoothContext),
.priv_class = &adynamicsmooth_class,
.uninit = uninit,
FILTER_INPUTS(inputs),
FILTER_OUTPUTS(ff_audio_default_filterpad),
FILTER_SINGLE_SAMPLEFMT(AV_SAMPLE_FMT_DBLP),
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
.process_command = ff_filter_process_command,
};
|
