FFmpeg
asrc_anoisesrc.c
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1 /*
2  * Copyright (c) 2015 Kyle Swanson <k@ylo.ph>.
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public License
8  * as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public License
17  * along with FFmpeg; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/opt.h"
22 #include "audio.h"
23 #include "avfilter.h"
24 #include "internal.h"
25 #include "libavutil/lfg.h"
26 #include "libavutil/random_seed.h"
27 
28 typedef struct ANoiseSrcContext {
29  const AVClass *class;
30  int sample_rate;
31  double amplitude;
32  int64_t duration;
33  int64_t color;
34  int64_t seed;
35  int nb_samples;
36 
37  int64_t pts;
38  int infinite;
39  double (*filter)(double white, double *buf);
40  double buf[7];
41  AVLFG c;
42 } ANoiseSrcContext;
43 
44 enum NoiseMode {
45  NM_WHITE,
46  NM_PINK,
47  NM_BROWN,
48  NM_BLUE,
49  NM_VIOLET,
50  NM_NB
51 };
52 
53 #define OFFSET(x) offsetof(ANoiseSrcContext, x)
54 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
55 
56 static const AVOption anoisesrc_options[] = {
57  { "sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
58  { "r", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
59  { "amplitude", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
60  { "a", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
61  { "duration", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
62  { "d", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
63  { "color", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
64  { "colour", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
65  { "c", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
66  { "white", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_WHITE}, 0, 0, FLAGS, "color" },
67  { "pink", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_PINK}, 0, 0, FLAGS, "color" },
68  { "brown", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BROWN}, 0, 0, FLAGS, "color" },
69  { "blue", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BLUE}, 0, 0, FLAGS, "color" },
70  { "violet", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_VIOLET}, 0, 0, FLAGS, "color" },
71  { "seed", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
72  { "s", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
73  { "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
74  { "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
75  {NULL}
76 };
77 
78 AVFILTER_DEFINE_CLASS(anoisesrc);
79 
80 static av_cold int query_formats(AVFilterContext *ctx)
81 {
82  ANoiseSrcContext *s = ctx->priv;
83  static const int64_t chlayouts[] = { AV_CH_LAYOUT_MONO, -1 };
84  int sample_rates[] = { s->sample_rate, -1 };
85  static const enum AVSampleFormat sample_fmts[] = {
86  AV_SAMPLE_FMT_DBL,
87  AV_SAMPLE_FMT_NONE
88  };
89 
90  AVFilterFormats *formats;
91  AVFilterChannelLayouts *layouts;
92  int ret;
93 
94  formats = ff_make_format_list(sample_fmts);
95  if (!formats)
96  return AVERROR(ENOMEM);
97  ret = ff_set_common_formats (ctx, formats);
98  if (ret < 0)
99  return ret;
100 
101  layouts = avfilter_make_format64_list(chlayouts);
102  if (!layouts)
103  return AVERROR(ENOMEM);
104  ret = ff_set_common_channel_layouts(ctx, layouts);
105  if (ret < 0)
106  return ret;
107 
108  formats = ff_make_format_list(sample_rates);
109  if (!formats)
110  return AVERROR(ENOMEM);
111  return ff_set_common_samplerates(ctx, formats);
112 }
113 
114 static double white_filter(double white, double *buf)
115 {
116  return white;
117 }
118 
119 static double pink_filter(double white, double *buf)
120 {
121  double pink;
122 
123  /* http://www.musicdsp.org/files/pink.txt */
124  buf[0] = 0.99886 * buf[0] + white * 0.0555179;
125  buf[1] = 0.99332 * buf[1] + white * 0.0750759;
126  buf[2] = 0.96900 * buf[2] + white * 0.1538520;
127  buf[3] = 0.86650 * buf[3] + white * 0.3104856;
128  buf[4] = 0.55000 * buf[4] + white * 0.5329522;
129  buf[5] = -0.7616 * buf[5] - white * 0.0168980;
130  pink = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
131  buf[6] = white * 0.115926;
132  return pink * 0.11;
133 }
134 
135 static double blue_filter(double white, double *buf)
136 {
137  double blue;
138 
139  /* Same as pink_filter but subtract the offsets rather than add */
140  buf[0] = 0.0555179 * white - 0.99886 * buf[0];
141  buf[1] = 0.0750759 * white - 0.99332 * buf[1];
142  buf[2] = 0.1538520 * white - 0.96900 * buf[2];
143  buf[3] = 0.3104856 * white - 0.86650 * buf[3];
144  buf[4] = 0.5329522 * white - 0.55000 * buf[4];
145  buf[5] = -0.016898 * white + 0.76160 * buf[5];
146  blue = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
147  buf[6] = white * 0.115926;
148  return blue * 0.11;
149 }
150 
151 static double brown_filter(double white, double *buf)
152 {
153  double brown;
154 
155  brown = ((0.02 * white) + buf[0]) / 1.02;
156  buf[0] = brown;
157  return brown * 3.5;
158 }
159 
160 static double violet_filter(double white, double *buf)
161 {
162  double violet;
163 
164  violet = ((0.02 * white) - buf[0]) / 1.02;
165  buf[0] = violet;
166  return violet * 3.5;
167 }
168 
169 static av_cold int config_props(AVFilterLink *outlink)
170 {
171  AVFilterContext *ctx = outlink->src;
172  ANoiseSrcContext *s = ctx->priv;
173 
174  if (s->seed == -1)
175  s->seed = av_get_random_seed();
176  av_lfg_init(&s->c, s->seed);
177 
178  if (s->duration == 0)
179  s->infinite = 1;
180  s->duration = av_rescale(s->duration, s->sample_rate, AV_TIME_BASE);
181 
182  switch (s->color) {
183  case NM_WHITE: s->filter = white_filter; break;
184  case NM_PINK: s->filter = pink_filter; break;
185  case NM_BROWN: s->filter = brown_filter; break;
186  case NM_BLUE: s->filter = blue_filter; break;
187  case NM_VIOLET: s->filter = violet_filter; break;
188  }
189 
190  return 0;
191 }
192 
193 static int request_frame(AVFilterLink *outlink)
194 {
195  AVFilterContext *ctx = outlink->src;
196  ANoiseSrcContext *s = ctx->priv;
197  AVFrame *frame;
198  int nb_samples, i;
199  double *dst;
200 
201  if (!s->infinite && s->duration <= 0) {
202  return AVERROR_EOF;
203  } else if (!s->infinite && s->duration < s->nb_samples) {
204  nb_samples = s->duration;
205  } else {
206  nb_samples = s->nb_samples;
207  }
208 
209  if (!(frame = ff_get_audio_buffer(outlink, nb_samples)))
210  return AVERROR(ENOMEM);
211 
212  dst = (double *)frame->data[0];
213  for (i = 0; i < nb_samples; i++) {
214  double white;
215  white = s->amplitude * ((2 * ((double) av_lfg_get(&s->c) / 0xffffffff)) - 1);
216  dst[i] = s->filter(white, s->buf);
217  }
218 
219  if (!s->infinite)
220  s->duration -= nb_samples;
221 
222  frame->pts = s->pts;
223  s->pts += nb_samples;
224  return ff_filter_frame(outlink, frame);
225 }
226 
227 static const AVFilterPad anoisesrc_outputs[] = {
228  {
229  .name = "default",
230  .type = AVMEDIA_TYPE_AUDIO,
231  .request_frame = request_frame,
232  .config_props = config_props,
233  },
234  { NULL }
235 };
236 
237 AVFilter ff_asrc_anoisesrc = {
238  .name = "anoisesrc",
239  .description = NULL_IF_CONFIG_SMALL("Generate a noise audio signal."),
240  .query_formats = query_formats,
241  .priv_size = sizeof(ANoiseSrcContext),
242  .inputs = NULL,
243  .outputs = anoisesrc_outputs,
244  .priv_class = &anoisesrc_class,
245 };
formats
formats
Definition: signature.h:48
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:86
AVFilterChannelLayouts
A list of supported channel layouts.
Definition: formats.h:85
NM_PINK
@ NM_PINK
Definition: asrc_anoisesrc.c:46
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
anoisesrc_options
static const AVOption anoisesrc_options[]
Definition: asrc_anoisesrc.c:56
ff_make_format_list
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
color
Definition: vf_paletteuse.c:588
av_lfg_init
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
violet_filter
static double violet_filter(double white, double *buf)
Definition: asrc_anoisesrc.c:160
ff_set_common_channel_layouts
int ff_set_common_channel_layouts(AVFilterContext *ctx, AVFilterChannelLayouts *layouts)
A helper for query_formats() which sets all links to the same list of channel layouts/sample rates.
Definition: formats.c:549
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:686
layouts
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:55
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:85
brown_filter
static double brown_filter(double white, double *buf)
Definition: asrc_anoisesrc.c:151
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption
AVOption.
Definition: opt.h:246
ANoiseSrcContext::c
AVLFG c
Definition: asrc_anoisesrc.c:41
NoiseMode
NoiseMode
Definition: asrc_anoisesrc.c:44
AV_OPT_TYPE_DURATION
@ AV_OPT_TYPE_DURATION
Definition: opt.h:237
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:148
sample_rate
sample_rate
Definition: ffmpeg_filter.c:191
av_get_random_seed
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:120
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
anoisesrc_outputs
static const AVFilterPad anoisesrc_outputs[]
Definition: asrc_anoisesrc.c:227
ff_asrc_anoisesrc
AVFilter ff_asrc_anoisesrc
Definition: asrc_anoisesrc.c:237
ANoiseSrcContext
Definition: asrc_anoisesrc.c:28
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:54
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(anoisesrc)
buf
void * buf
Definition: avisynth_c.h:766
av_cold
#define av_cold
Definition: attributes.h:84
ff_set_common_formats
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:568
NM_WHITE
@ NM_WHITE
Definition: asrc_anoisesrc.c:45
duration
int64_t duration
Definition: movenc.c:63
s
#define s(width, name)
Definition: cbs_vp9.c:257
av_lfg_get
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:53
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:225
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
lfg.h
AV_OPT_TYPE_INT64
@ AV_OPT_TYPE_INT64
Definition: opt.h:224
outputs
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
NM_VIOLET
@ NM_VIOLET
Definition: asrc_anoisesrc.c:49
ctx
AVFormatContext * ctx
Definition: movenc.c:48
NM_NB
@ NM_NB
Definition: asrc_anoisesrc.c:50
NM_BROWN
@ NM_BROWN
Definition: asrc_anoisesrc.c:47
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
NULL
#define NULL
Definition: coverity.c:32
ANoiseSrcContext::infinite
int infinite
Definition: asrc_anoisesrc.c:38
query_formats
static av_cold int query_formats(AVFilterContext *ctx)
Definition: asrc_anoisesrc.c:80
ANoiseSrcContext::amplitude
double amplitude
Definition: asrc_anoisesrc.c:31
inputs
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Definition: filter_design.txt:243
seed
static unsigned int seed
Definition: videogen.c:78
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
AVLFG
Context structure for the Lagged Fibonacci PRNG.
Definition: lfg.h:33
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:188
blue_filter
static double blue_filter(double white, double *buf)
Definition: asrc_anoisesrc.c:135
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
config_props
static av_cold int config_props(AVFilterLink *outlink)
Definition: asrc_anoisesrc.c:169
ANoiseSrcContext::pts
int64_t pts
Definition: asrc_anoisesrc.c:37
sample_rates
sample_rates
Definition: ffmpeg_filter.c:191
internal.h
avfilter_make_format64_list
AVFilterChannelLayouts * avfilter_make_format64_list(const int64_t *fmts)
Definition: formats.c:303
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
AV_TIME_BASE
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
ANoiseSrcContext::sample_rate
int sample_rate
Definition: asrc_anoisesrc.c:30
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
OFFSET
#define OFFSET(x)
Definition: asrc_anoisesrc.c:53
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:60
av_rescale
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:129
NM_BLUE
@ NM_BLUE
Definition: asrc_anoisesrc.c:48
AVFilter
Filter definition.
Definition: avfilter.h:144
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
ANoiseSrcContext::color
int64_t color
Definition: asrc_anoisesrc.c:33
FLAGS
#define FLAGS
Definition: asrc_anoisesrc.c:54
ANoiseSrcContext::seed
int64_t seed
Definition: asrc_anoisesrc.c:34
random_seed.h
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:223
avfilter.h
ANoiseSrcContext::nb_samples
int nb_samples
Definition: asrc_anoisesrc.c:35
AVFilterContext
An instance of a filter.
Definition: avfilter.h:338
ANoiseSrcContext::buf
double buf[7]
Definition: asrc_anoisesrc.c:40
audio.h
white_filter
static double white_filter(double white, double *buf)
Definition: asrc_anoisesrc.c:114
request_frame
static int request_frame(AVFilterLink *outlink)
Definition: asrc_anoisesrc.c:193
ANoiseSrcContext::filter
double(* filter)(double white, double *buf)
Definition: asrc_anoisesrc.c:39
ff_set_common_samplerates
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:556
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:64
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:232
pink_filter
static double pink_filter(double white, double *buf)
Definition: asrc_anoisesrc.c:119
ANoiseSrcContext::duration
int64_t duration
Definition: asrc_anoisesrc.c:32
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