FFmpeg
af_acontrast.c
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1 /*
2  * Copyright (c) 2008 Rob Sykes
3  * Copyright (c) 2017 Paul B Mahol
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
23 #include "libavutil/opt.h"
24 #include "avfilter.h"
25 #include "audio.h"
26 #include "formats.h"
27 
28 typedef struct AudioContrastContext {
29  const AVClass *class;
30  float contrast;
31  void (*filter)(void **dst, const void **src,
32  int nb_samples, int channels, float contrast);
34 
35 #define OFFSET(x) offsetof(AudioContrastContext, x)
36 #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
37 
38 static const AVOption acontrast_options[] = {
39  { "contrast", "set contrast", OFFSET(contrast), AV_OPT_TYPE_FLOAT, {.dbl=33}, 0, 100, A },
40  { NULL }
41 };
42 
43 AVFILTER_DEFINE_CLASS(acontrast);
44 
45 static void filter_flt(void **d, const void **s,
46  int nb_samples, int channels,
47  float contrast)
48 {
49  const float *src = s[0];
50  float *dst = d[0];
51  int n, c;
52 
53  for (n = 0; n < nb_samples; n++) {
54  for (c = 0; c < channels; c++) {
55  float d = src[c] * M_PI_2;
56 
57  dst[c] = sinf(d + contrast * sinf(d * 4));
58  }
59 
60  dst += c;
61  src += c;
62  }
63 }
64 
65 static void filter_dbl(void **d, const void **s,
66  int nb_samples, int channels,
67  float contrast)
68 {
69  const double *src = s[0];
70  double *dst = d[0];
71  int n, c;
72 
73  for (n = 0; n < nb_samples; n++) {
74  for (c = 0; c < channels; c++) {
75  double d = src[c] * M_PI_2;
76 
77  dst[c] = sin(d + contrast * sin(d * 4));
78  }
79 
80  dst += c;
81  src += c;
82  }
83 }
84 
85 static void filter_fltp(void **d, const void **s,
86  int nb_samples, int channels,
87  float contrast)
88 {
89  int n, c;
90 
91  for (c = 0; c < channels; c++) {
92  const float *src = s[c];
93  float *dst = d[c];
94 
95  for (n = 0; n < nb_samples; n++) {
96  float d = src[n] * M_PI_2;
97 
98  dst[n] = sinf(d + contrast * sinf(d * 4));
99  }
100  }
101 }
102 
103 static void filter_dblp(void **d, const void **s,
104  int nb_samples, int channels,
105  float contrast)
106 {
107  int n, c;
108 
109  for (c = 0; c < channels; c++) {
110  const double *src = s[c];
111  double *dst = d[c];
112 
113  for (n = 0; n < nb_samples; n++) {
114  double d = src[n] * M_PI_2;
115 
116  dst[n] = sin(d + contrast * sin(d * 4));
117  }
118  }
119 }
120 
122 {
123  AVFilterContext *ctx = inlink->dst;
124  AudioContrastContext *s = ctx->priv;
125 
126  switch (inlink->format) {
127  case AV_SAMPLE_FMT_FLT: s->filter = filter_flt; break;
128  case AV_SAMPLE_FMT_DBL: s->filter = filter_dbl; break;
129  case AV_SAMPLE_FMT_FLTP: s->filter = filter_fltp; break;
130  case AV_SAMPLE_FMT_DBLP: s->filter = filter_dblp; break;
131  }
132 
133  return 0;
134 }
135 
137 {
138  AVFilterContext *ctx = inlink->dst;
139  AVFilterLink *outlink = ctx->outputs[0];
140  AudioContrastContext *s = ctx->priv;
141  AVFrame *out;
142 
143  if (av_frame_is_writable(in)) {
144  out = in;
145  } else {
146  out = ff_get_audio_buffer(outlink, in->nb_samples);
147  if (!out) {
148  av_frame_free(&in);
149  return AVERROR(ENOMEM);
150  }
152  }
153 
154  s->filter((void **)out->extended_data, (const void **)in->extended_data,
155  in->nb_samples, in->channels, s->contrast / 750);
156 
157  if (out != in)
158  av_frame_free(&in);
159 
160  return ff_filter_frame(outlink, out);
161 }
162 
163 static const AVFilterPad inputs[] = {
164  {
165  .name = "default",
166  .type = AVMEDIA_TYPE_AUDIO,
167  .filter_frame = filter_frame,
168  .config_props = config_input,
169  },
170 };
171 
172 static const AVFilterPad outputs[] = {
173  {
174  .name = "default",
175  .type = AVMEDIA_TYPE_AUDIO,
176  },
177 };
178 
180  .name = "acontrast",
181  .description = NULL_IF_CONFIG_SMALL("Simple audio dynamic range compression/expansion filter."),
182  .priv_size = sizeof(AudioContrastContext),
183  .priv_class = &acontrast_class,
188 };
ff_get_audio_buffer
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:88
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:69
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
out
FILE * out
Definition: movenc.c:54
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1018
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:112
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
M_PI_2
#define M_PI_2
Definition: mathematics.h:55
AVOption
AVOption.
Definition: opt.h:247
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(acontrast)
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
AudioContrastContext::contrast
float contrast
Definition: af_acontrast.c:30
acontrast_options
static const AVOption acontrast_options[]
Definition: af_acontrast.c:38
formats.h
AudioContrastContext
Definition: af_acontrast.c:28
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVFrame::channels
int channels
number of audio channels, only used for audio.
Definition: frame.h:592
filter_dbl
static void filter_dbl(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:65
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:172
ctx
AVFormatContext * ctx
Definition: movenc.c:48
channels
channels
Definition: aptx.h:33
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:191
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AudioContrastContext::filter
void(* filter)(void **dst, const void **src, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:31
av_frame_copy_props
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:537
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_acontrast.c:121
src
#define src
Definition: vp8dsp.c:255
sinf
#define sinf(x)
Definition: libm.h:419
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
OFFSET
#define OFFSET(x)
Definition: af_acontrast.c:35
filter_flt
static void filter_flt(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:45
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:473
ff_af_acontrast
const AVFilter ff_af_acontrast
Definition: af_acontrast.c:179
A
#define A
Definition: af_acontrast.c:36
AV_OPT_TYPE_FLOAT
@ AV_OPT_TYPE_FLOAT
Definition: opt.h:227
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:369
AVFrame::extended_data
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:350
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
AVFilter
Filter definition.
Definition: avfilter.h:149
filter_fltp
static void filter_fltp(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:85
channel_layout.h
avfilter.h
inputs
static const AVFilterPad inputs[]
Definition: af_acontrast.c:163
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:70
AVFilterContext
An instance of a filter.
Definition: avfilter.h:386
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_acontrast.c:136
audio.h
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:192
d
d
Definition: ffmpeg_filter.c:156
filter_dblp
static void filter_dblp(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:103
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:64
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:63
FILTER_SAMPLEFMTS
#define FILTER_SAMPLEFMTS(...)
Definition: internal.h:179