FFmpeg
opusdsp.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "opusdsp.h"
20 
21 static void postfilter_c(float *data, int period, float *gains, int len)
22 {
23  const float g0 = gains[0];
24  const float g1 = gains[1];
25  const float g2 = gains[2];
26 
27  float x4 = data[-period - 2];
28  float x3 = data[-period - 1];
29  float x2 = data[-period + 0];
30  float x1 = data[-period + 1];
31 
32  for (int i = 0; i < len; i++) {
33  float x0 = data[i - period + 2];
34  data[i] += g0 * x2 +
35  g1 * (x1 + x3) +
36  g2 * (x0 + x4);
37  x4 = x3;
38  x3 = x2;
39  x2 = x1;
40  x1 = x0;
41  }
42 }
43 
44 static float deemphasis_c(float *y, float *x, float coeff, int len)
45 {
46  for (int i = 0; i < len; i++)
47  coeff = y[i] = x[i] + coeff*CELT_EMPH_COEFF;
48 
49  return coeff;
50 }
51 
53 {
54  ctx->postfilter = postfilter_c;
55  ctx->deemphasis = deemphasis_c;
56 
57  if (ARCH_X86)
59 
60  if (ARCH_AARCH64)
62 }
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
float(* deemphasis)(float *out, float *in, float coeff, int len)
Definition: opusdsp.h:28
#define av_cold
Definition: attributes.h:82
static float deemphasis_c(float *y, float *x, float coeff, int len)
Definition: opusdsp.c:44
static void postfilter_c(float *data, int period, float *gains, int len)
Definition: opusdsp.c:21
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option keep it simple and lowercase description are in without period
AVFormatContext * ctx
Definition: movenc.c:48
av_cold void ff_opus_dsp_init_aarch64(OpusDSP *ctx)
Definition: opusdsp_init.c:27
void ff_opus_dsp_init_x86(OpusDSP *ctx)
Definition: opusdsp_init.c:27
av_cold void ff_opus_dsp_init(OpusDSP *ctx)
Definition: opusdsp.c:52
int len
static const double coeff[2][5]
Definition: vf_owdenoise.c:72
void(* postfilter)(float *data, int period, float *gains, int len)
Definition: opusdsp.h:27
#define CELT_EMPH_COEFF
Definition: opusdsp.h:24