FFmpeg  4.3.8
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 "filters.h"
25 #include "internal.h"
26 #include "libavutil/lfg.h"
27 #include "libavutil/random_seed.h"
28 
29 typedef struct ANoiseSrcContext {
30  const AVClass *class;
32  double amplitude;
34  int color;
37 
39  int infinite;
40  double (*filter)(double white, double *buf, double half_amplitude);
41  double buf[7];
44 
45 enum NoiseMode {
53 };
54 
55 #define OFFSET(x) offsetof(ANoiseSrcContext, x)
56 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
57 
58 static const AVOption anoisesrc_options[] = {
59  { "sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
60  { "r", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
61  { "amplitude", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
62  { "a", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
63  { "duration", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
64  { "d", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
65  { "color", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
66  { "colour", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
67  { "c", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
68  { "white", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_WHITE}, 0, 0, FLAGS, "color" },
69  { "pink", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_PINK}, 0, 0, FLAGS, "color" },
70  { "brown", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BROWN}, 0, 0, FLAGS, "color" },
71  { "blue", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BLUE}, 0, 0, FLAGS, "color" },
72  { "violet", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_VIOLET}, 0, 0, FLAGS, "color" },
73  { "velvet", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_VELVET}, 0, 0, FLAGS, "color" },
74  { "seed", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
75  { "s", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
76  { "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
77  { "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
78  {NULL}
79 };
80 
81 AVFILTER_DEFINE_CLASS(anoisesrc);
82 
84 {
85  ANoiseSrcContext *s = ctx->priv;
86  static const int64_t chlayouts[] = { AV_CH_LAYOUT_MONO, -1 };
87  int sample_rates[] = { s->sample_rate, -1 };
88  static const enum AVSampleFormat sample_fmts[] = {
91  };
92 
95  int ret;
96 
97  formats = ff_make_format_list(sample_fmts);
98  if (!formats)
99  return AVERROR(ENOMEM);
100  ret = ff_set_common_formats (ctx, formats);
101  if (ret < 0)
102  return ret;
103 
104  layouts = avfilter_make_format64_list(chlayouts);
105  if (!layouts)
106  return AVERROR(ENOMEM);
107  ret = ff_set_common_channel_layouts(ctx, layouts);
108  if (ret < 0)
109  return ret;
110 
111  formats = ff_make_format_list(sample_rates);
112  if (!formats)
113  return AVERROR(ENOMEM);
114  return ff_set_common_samplerates(ctx, formats);
115 }
116 
117 static double white_filter(double white, double *buf, double ha)
118 {
119  return white;
120 }
121 
122 static double pink_filter(double white, double *buf, double ha)
123 {
124  double pink;
125 
126  /* http://www.musicdsp.org/files/pink.txt */
127  buf[0] = 0.99886 * buf[0] + white * 0.0555179;
128  buf[1] = 0.99332 * buf[1] + white * 0.0750759;
129  buf[2] = 0.96900 * buf[2] + white * 0.1538520;
130  buf[3] = 0.86650 * buf[3] + white * 0.3104856;
131  buf[4] = 0.55000 * buf[4] + white * 0.5329522;
132  buf[5] = -0.7616 * buf[5] - white * 0.0168980;
133  pink = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
134  buf[6] = white * 0.115926;
135  return pink * 0.11;
136 }
137 
138 static double blue_filter(double white, double *buf, double ha)
139 {
140  double blue;
141 
142  /* Same as pink_filter but subtract the offsets rather than add */
143  buf[0] = 0.0555179 * white - 0.99886 * buf[0];
144  buf[1] = 0.0750759 * white - 0.99332 * buf[1];
145  buf[2] = 0.1538520 * white - 0.96900 * buf[2];
146  buf[3] = 0.3104856 * white - 0.86650 * buf[3];
147  buf[4] = 0.5329522 * white - 0.55000 * buf[4];
148  buf[5] = -0.016898 * white + 0.76160 * buf[5];
149  blue = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
150  buf[6] = white * 0.115926;
151  return blue * 0.11;
152 }
153 
154 static double brown_filter(double white, double *buf, double ha)
155 {
156  double brown;
157 
158  brown = ((0.02 * white) + buf[0]) / 1.02;
159  buf[0] = brown;
160  return brown * 3.5;
161 }
162 
163 static double violet_filter(double white, double *buf, double ha)
164 {
165  double violet;
166 
167  violet = ((0.02 * white) - buf[0]) / 1.02;
168  buf[0] = violet;
169  return violet * 3.5;
170 }
171 
172 static double velvet_filter(double white, double *buf, double ha)
173 {
174  return 2. * ha * ((white > ha) - (white < -ha));
175 }
176 
177 static av_cold int config_props(AVFilterLink *outlink)
178 {
179  AVFilterContext *ctx = outlink->src;
180  ANoiseSrcContext *s = ctx->priv;
181 
182  if (s->seed == -1)
183  s->seed = av_get_random_seed();
184  av_lfg_init(&s->c, s->seed);
185 
186  if (s->duration == 0)
187  s->infinite = 1;
189 
190  switch (s->color) {
191  case NM_WHITE: s->filter = white_filter; break;
192  case NM_PINK: s->filter = pink_filter; break;
193  case NM_BROWN: s->filter = brown_filter; break;
194  case NM_BLUE: s->filter = blue_filter; break;
195  case NM_VIOLET: s->filter = violet_filter; break;
196  case NM_VELVET: s->filter = velvet_filter; break;
197  }
198 
199  return 0;
200 }
201 
203 {
204  AVFilterLink *outlink = ctx->outputs[0];
205  ANoiseSrcContext *s = ctx->priv;
206  AVFrame *frame;
207  int nb_samples, i;
208  double *dst;
209 
210  if (!ff_outlink_frame_wanted(outlink))
211  return FFERROR_NOT_READY;
212 
213  if (!s->infinite && s->duration <= 0) {
214  ff_outlink_set_status(outlink, AVERROR_EOF, s->pts);
215  return 0;
216  } else if (!s->infinite && s->duration < s->nb_samples) {
217  nb_samples = s->duration;
218  } else {
219  nb_samples = s->nb_samples;
220  }
221 
222  if (!(frame = ff_get_audio_buffer(outlink, nb_samples)))
223  return AVERROR(ENOMEM);
224 
225  dst = (double *)frame->data[0];
226  for (i = 0; i < nb_samples; i++) {
227  double white;
228  white = s->amplitude * ((2 * ((double) av_lfg_get(&s->c) / 0xffffffff)) - 1);
229  dst[i] = s->filter(white, s->buf, s->amplitude * 0.5);
230  }
231 
232  if (!s->infinite)
233  s->duration -= nb_samples;
234 
235  frame->pts = s->pts;
236  s->pts += nb_samples;
237  return ff_filter_frame(outlink, frame);
238 }
239 
240 static const AVFilterPad anoisesrc_outputs[] = {
241  {
242  .name = "default",
243  .type = AVMEDIA_TYPE_AUDIO,
244  .config_props = config_props,
245  },
246  { NULL }
247 };
248 
250  .name = "anoisesrc",
251  .description = NULL_IF_CONFIG_SMALL("Generate a noise audio signal."),
252  .query_formats = query_formats,
253  .priv_size = sizeof(ANoiseSrcContext),
254  .inputs = NULL,
255  .activate = activate,
256  .outputs = anoisesrc_outputs,
257  .priv_class = &anoisesrc_class,
258 };
Context structure for the Lagged Fibonacci PRNG.
Definition: lfg.h:33
#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:586
static double violet_filter(double white, double *buf, double ha)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:300
AVOption.
Definition: opt.h:246
Main libavfilter public API header.
static const AVOption anoisesrc_options[]
#define FFERROR_NOT_READY
Filters implementation helper functions.
Definition: filters.h:34
static void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
Set the status field of a link from the source filter.
Definition: filters.h:189
static double blue_filter(double white, double *buf, double ha)
static int ff_outlink_frame_wanted(AVFilterLink *link)
Test if a frame is wanted on an output link.
Definition: filters.h:172
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:300
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:1075
#define av_cold
Definition: attributes.h:88
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:393
static AVFrame * frame
AVFilter ff_asrc_anoisesrc
#define OFFSET(x)
#define AVERROR_EOF
End of file.
Definition: error.h:55
AVFILTER_DEFINE_CLASS(anoisesrc)
A filter pad used for either input or output.
Definition: internal.h:54
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
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:605
#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:188
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
static int activate(AVFilterContext *ctx)
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
static double brown_filter(double white, double *buf, double ha)
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
static double velvet_filter(double white, double *buf, double ha)
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:320
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
long long int64_t
Definition: coverity.c:34
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:53
Describe the class of an AVClass context structure.
Definition: log.h:67
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
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:314
static double pink_filter(double white, double *buf, double ha)
static const AVFilterPad anoisesrc_outputs[]
sample_rates
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:731
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
double(* filter)(double white, double *buf, double half_amplitude)
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:593
static double white_filter(double white, double *buf, double ha)