FFmpeg  4.0
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;
31  double amplitude;
32  int64_t duration;
33  int64_t color;
34  int64_t seed;
36 
37  int64_t pts;
38  int infinite;
39  double (*filter)(double white, double *buf);
40  double buf[7];
43 
44 enum NoiseMode {
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 
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[] = {
88  };
89 
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;
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 
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 };
Definition: lfg.h:27
#define NULL
Definition: coverity.c:32
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
const char * s
Definition: avisynth_c.h:768
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
AVOption.
Definition: opt.h:246
Main libavfilter public API header.
static const AVOption anoisesrc_options[]
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
const char * name
Pad name.
Definition: internal.h:60
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
#define av_cold
Definition: attributes.h:82
static av_cold int query_formats(AVFilterContext *ctx)
AVOptions.
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:311
static AVFrame * frame
AVFilter ff_asrc_anoisesrc
#define OFFSET(x)
#define AVERROR_EOF
End of file.
Definition: error.h:55
static int request_frame(AVFilterLink *outlink)
AVFILTER_DEFINE_CLASS(anoisesrc)
A filter pad used for either input or output.
Definition: internal.h:54
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
#define FLAGS
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
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
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
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
static double blue_filter(double white, double *buf)
AVFormatContext * ctx
Definition: movenc.c:48
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
A list of supported channel layouts.
Definition: formats.h:85
static av_cold int config_props(AVFilterLink *outlink)
AVFilterChannelLayouts * avfilter_make_format64_list(const int64_t *fmts)
Definition: formats.c:303
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
static double white_filter(double white, double *buf)
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:47
double(* filter)(double white, double *buf)
Describe the class of an AVClass context structure.
Definition: log.h:67
static double brown_filter(double white, double *buf)
Filter definition.
Definition: avfilter.h:144
const char * name
Filter name.
Definition: avfilter.h:148
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
NoiseMode
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
static double pink_filter(double white, double *buf)
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
static const AVFilterPad anoisesrc_outputs[]
sample_rates
static double violet_filter(double white, double *buf)
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:701
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:120
formats
Definition: signature.h:48
internal API functions
#define AV_CH_LAYOUT_MONO
for(j=16;j >0;--j)
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:556