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 
27 typedef struct AudioContrastContext {
28  const AVClass *class;
29  float contrast;
30  void (*filter)(void **dst, const void **src,
31  int nb_samples, int channels, float contrast);
33 
34 #define OFFSET(x) offsetof(AudioContrastContext, x)
35 #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
36 
37 static const AVOption acontrast_options[] = {
38  { "contrast", "set contrast", OFFSET(contrast), AV_OPT_TYPE_FLOAT, {.dbl=33}, 0, 100, A },
39  { NULL }
40 };
41 
42 AVFILTER_DEFINE_CLASS(acontrast);
43 
44 static void filter_flt(void **d, const void **s,
45  int nb_samples, int channels,
46  float contrast)
47 {
48  const float *src = s[0];
49  float *dst = d[0];
50  int n, c;
51 
52  for (n = 0; n < nb_samples; n++) {
53  for (c = 0; c < channels; c++) {
54  float d = src[c] * M_PI_2;
55 
56  dst[c] = sinf(d + contrast * sinf(d * 4));
57  }
58 
59  dst += c;
60  src += c;
61  }
62 }
63 
64 static void filter_dbl(void **d, const void **s,
65  int nb_samples, int channels,
66  float contrast)
67 {
68  const double *src = s[0];
69  double *dst = d[0];
70  int n, c;
71 
72  for (n = 0; n < nb_samples; n++) {
73  for (c = 0; c < channels; c++) {
74  double d = src[c] * M_PI_2;
75 
76  dst[c] = sin(d + contrast * sin(d * 4));
77  }
78 
79  dst += c;
80  src += c;
81  }
82 }
83 
84 static void filter_fltp(void **d, const void **s,
85  int nb_samples, int channels,
86  float contrast)
87 {
88  int n, c;
89 
90  for (c = 0; c < channels; c++) {
91  const float *src = s[c];
92  float *dst = d[c];
93 
94  for (n = 0; n < nb_samples; n++) {
95  float d = src[n] * M_PI_2;
96 
97  dst[n] = sinf(d + contrast * sinf(d * 4));
98  }
99  }
100 }
101 
102 static void filter_dblp(void **d, const void **s,
103  int nb_samples, int channels,
104  float contrast)
105 {
106  int n, c;
107 
108  for (c = 0; c < channels; c++) {
109  const double *src = s[c];
110  double *dst = d[c];
111 
112  for (n = 0; n < nb_samples; n++) {
113  double d = src[n] * M_PI_2;
114 
115  dst[n] = sin(d + contrast * sin(d * 4));
116  }
117  }
118 }
119 
121 {
122  AVFilterContext *ctx = inlink->dst;
123  AudioContrastContext *s = ctx->priv;
124 
125  switch (inlink->format) {
126  case AV_SAMPLE_FMT_FLT: s->filter = filter_flt; break;
127  case AV_SAMPLE_FMT_DBL: s->filter = filter_dbl; break;
128  case AV_SAMPLE_FMT_FLTP: s->filter = filter_fltp; break;
129  case AV_SAMPLE_FMT_DBLP: s->filter = filter_dblp; break;
130  }
131 
132  return 0;
133 }
134 
136 {
137  AVFilterContext *ctx = inlink->dst;
138  AVFilterLink *outlink = ctx->outputs[0];
139  AudioContrastContext *s = ctx->priv;
140  AVFrame *out;
141 
142  if (av_frame_is_writable(in)) {
143  out = in;
144  } else {
145  out = ff_get_audio_buffer(outlink, in->nb_samples);
146  if (!out) {
147  av_frame_free(&in);
148  return AVERROR(ENOMEM);
149  }
151  }
152 
153  s->filter((void **)out->extended_data, (const void **)in->extended_data,
154  in->nb_samples, in->ch_layout.nb_channels, s->contrast / 750);
155 
156  if (out != in)
157  av_frame_free(&in);
158 
159  return ff_filter_frame(outlink, out);
160 }
161 
162 static const AVFilterPad inputs[] = {
163  {
164  .name = "default",
165  .type = AVMEDIA_TYPE_AUDIO,
166  .filter_frame = filter_frame,
167  .config_props = config_input,
168  },
169 };
170 
172  .name = "acontrast",
173  .description = NULL_IF_CONFIG_SMALL("Simple audio dynamic range compression/expansion filter."),
174  .priv_size = sizeof(AudioContrastContext),
175  .priv_class = &acontrast_class,
180 };
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:97
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:66
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:88
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
M_PI_2
#define M_PI_2
Definition: mathematics.h:73
AVOption
AVOption.
Definition: opt.h:346
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(acontrast)
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:170
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:313
AudioContrastContext::contrast
float contrast
Definition: af_acontrast.c:29
acontrast_options
static const AVOption acontrast_options[]
Definition: af_acontrast.c:37
AVFrame::ch_layout
AVChannelLayout ch_layout
Channel layout of the audio data.
Definition: frame.h:741
AudioContrastContext
Definition: af_acontrast.c:27
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:33
s
#define s(width, name)
Definition: cbs_vp9.c:198
filter_dbl
static void filter_dbl(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:64
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ctx
AVFormatContext * ctx
Definition: movenc.c:48
channels
channels
Definition: aptx.h:31
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:182
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:30
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:637
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_acontrast.c:120
ff_audio_default_filterpad
const AVFilterPad ff_audio_default_filterpad[1]
An AVFilterPad array whose only entry has name "default" and is of type AVMEDIA_TYPE_AUDIO.
Definition: audio.c:33
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:34
filter_flt
static void filter_flt(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:44
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:106
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:573
ff_af_acontrast
const AVFilter ff_af_acontrast
Definition: af_acontrast.c:171
A
#define A
Definition: af_acontrast.c:35
AV_OPT_TYPE_FLOAT
@ AV_OPT_TYPE_FLOAT
Definition: opt.h:238
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:420
AVFrame::extended_data
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:401
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:39
AVFilter
Filter definition.
Definition: avfilter.h:166
filter_fltp
static void filter_fltp(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:84
channel_layout.h
avfilter.h
inputs
static const AVFilterPad inputs[]
Definition: af_acontrast.c:162
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:67
AVFilterContext
An instance of a filter.
Definition: avfilter.h:407
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_acontrast.c:135
audio.h
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:183
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
d
d
Definition: ffmpeg_filter.c:425
filter_dblp
static void filter_dblp(void **d, const void **s, int nb_samples, int channels, float contrast)
Definition: af_acontrast.c:102
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:61
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:60
FILTER_SAMPLEFMTS
#define FILTER_SAMPLEFMTS(...)
Definition: internal.h:170