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;
31  double amplitude;
32  int64_t duration;
33  int color;
34  int64_t seed;
36 
37  int64_t pts;
38  int infinite;
39  double (*filter)(double white, double *buf, double half_amplitude);
40  double buf[7];
43 
44 enum NoiseMode {
52 };
53 
54 #define OFFSET(x) offsetof(ANoiseSrcContext, x)
55 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
56 
57 static const AVOption anoisesrc_options[] = {
58  { "sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
59  { "r", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
60  { "amplitude", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
61  { "a", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
62  { "duration", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
63  { "d", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
64  { "color", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
65  { "colour", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
66  { "c", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
67  { "white", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_WHITE}, 0, 0, FLAGS, "color" },
68  { "pink", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_PINK}, 0, 0, FLAGS, "color" },
69  { "brown", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BROWN}, 0, 0, FLAGS, "color" },
70  { "blue", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BLUE}, 0, 0, FLAGS, "color" },
71  { "violet", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_VIOLET}, 0, 0, FLAGS, "color" },
72  { "velvet", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_VELVET}, 0, 0, FLAGS, "color" },
73  { "seed", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
74  { "s", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
75  { "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
76  { "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
77  {NULL}
78 };
79 
80 AVFILTER_DEFINE_CLASS(anoisesrc);
81 
83 {
84  ANoiseSrcContext *s = ctx->priv;
85  static const int64_t chlayouts[] = { AV_CH_LAYOUT_MONO, -1 };
86  int sample_rates[] = { s->sample_rate, -1 };
87  static const enum AVSampleFormat sample_fmts[] = {
90  };
91 
94  int ret;
95 
96  formats = ff_make_format_list(sample_fmts);
97  if (!formats)
98  return AVERROR(ENOMEM);
99  ret = ff_set_common_formats (ctx, formats);
100  if (ret < 0)
101  return ret;
102 
103  layouts = avfilter_make_format64_list(chlayouts);
104  if (!layouts)
105  return AVERROR(ENOMEM);
106  ret = ff_set_common_channel_layouts(ctx, layouts);
107  if (ret < 0)
108  return ret;
109 
110  formats = ff_make_format_list(sample_rates);
111  if (!formats)
112  return AVERROR(ENOMEM);
113  return ff_set_common_samplerates(ctx, formats);
114 }
115 
116 static double white_filter(double white, double *buf, double ha)
117 {
118  return white;
119 }
120 
121 static double pink_filter(double white, double *buf, double ha)
122 {
123  double pink;
124 
125  /* http://www.musicdsp.org/files/pink.txt */
126  buf[0] = 0.99886 * buf[0] + white * 0.0555179;
127  buf[1] = 0.99332 * buf[1] + white * 0.0750759;
128  buf[2] = 0.96900 * buf[2] + white * 0.1538520;
129  buf[3] = 0.86650 * buf[3] + white * 0.3104856;
130  buf[4] = 0.55000 * buf[4] + white * 0.5329522;
131  buf[5] = -0.7616 * buf[5] - white * 0.0168980;
132  pink = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
133  buf[6] = white * 0.115926;
134  return pink * 0.11;
135 }
136 
137 static double blue_filter(double white, double *buf, double ha)
138 {
139  double blue;
140 
141  /* Same as pink_filter but subtract the offsets rather than add */
142  buf[0] = 0.0555179 * white - 0.99886 * buf[0];
143  buf[1] = 0.0750759 * white - 0.99332 * buf[1];
144  buf[2] = 0.1538520 * white - 0.96900 * buf[2];
145  buf[3] = 0.3104856 * white - 0.86650 * buf[3];
146  buf[4] = 0.5329522 * white - 0.55000 * buf[4];
147  buf[5] = -0.016898 * white + 0.76160 * buf[5];
148  blue = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
149  buf[6] = white * 0.115926;
150  return blue * 0.11;
151 }
152 
153 static double brown_filter(double white, double *buf, double ha)
154 {
155  double brown;
156 
157  brown = ((0.02 * white) + buf[0]) / 1.02;
158  buf[0] = brown;
159  return brown * 3.5;
160 }
161 
162 static double violet_filter(double white, double *buf, double ha)
163 {
164  double violet;
165 
166  violet = ((0.02 * white) - buf[0]) / 1.02;
167  buf[0] = violet;
168  return violet * 3.5;
169 }
170 
171 static double velvet_filter(double white, double *buf, double ha)
172 {
173  return 2. * ha * ((white > ha) - (white < -ha));
174 }
175 
176 static av_cold int config_props(AVFilterLink *outlink)
177 {
178  AVFilterContext *ctx = outlink->src;
179  ANoiseSrcContext *s = ctx->priv;
180 
181  if (s->seed == -1)
182  s->seed = av_get_random_seed();
183  av_lfg_init(&s->c, s->seed);
184 
185  if (s->duration == 0)
186  s->infinite = 1;
188 
189  switch (s->color) {
190  case NM_WHITE: s->filter = white_filter; break;
191  case NM_PINK: s->filter = pink_filter; break;
192  case NM_BROWN: s->filter = brown_filter; break;
193  case NM_BLUE: s->filter = blue_filter; break;
194  case NM_VIOLET: s->filter = violet_filter; break;
195  case NM_VELVET: s->filter = velvet_filter; break;
196  }
197 
198  return 0;
199 }
200 
201 static int request_frame(AVFilterLink *outlink)
202 {
203  AVFilterContext *ctx = outlink->src;
204  ANoiseSrcContext *s = ctx->priv;
205  AVFrame *frame;
206  int nb_samples, i;
207  double *dst;
208 
209  if (!s->infinite && s->duration <= 0) {
210  return AVERROR_EOF;
211  } else if (!s->infinite && s->duration < s->nb_samples) {
212  nb_samples = s->duration;
213  } else {
214  nb_samples = s->nb_samples;
215  }
216 
217  if (!(frame = ff_get_audio_buffer(outlink, nb_samples)))
218  return AVERROR(ENOMEM);
219 
220  dst = (double *)frame->data[0];
221  for (i = 0; i < nb_samples; i++) {
222  double white;
223  white = s->amplitude * ((2 * ((double) av_lfg_get(&s->c) / 0xffffffff)) - 1);
224  dst[i] = s->filter(white, s->buf, s->amplitude * 0.5);
225  }
226 
227  if (!s->infinite)
228  s->duration -= nb_samples;
229 
230  frame->pts = s->pts;
231  s->pts += nb_samples;
232  return ff_filter_frame(outlink, frame);
233 }
234 
235 static const AVFilterPad anoisesrc_outputs[] = {
236  {
237  .name = "default",
238  .type = AVMEDIA_TYPE_AUDIO,
239  .request_frame = request_frame,
240  .config_props = config_props,
241  },
242  { NULL }
243 };
244 
246  .name = "anoisesrc",
247  .description = NULL_IF_CONFIG_SMALL("Generate a noise audio signal."),
248  .query_formats = query_formats,
249  .priv_size = sizeof(ANoiseSrcContext),
250  .inputs = NULL,
251  .outputs = anoisesrc_outputs,
252  .priv_class = &anoisesrc_class,
253 };
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:550
static double violet_filter(double white, double *buf, double ha)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
Main libavfilter public API header.
static const AVOption anoisesrc_options[]
static double blue_filter(double white, double *buf, double ha)
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:1075
#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:388
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
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
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:569
#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 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 brown_filter(double white, double *buf, double ha)
AVFormatContext * ctx
Definition: movenc.c:48
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
#define s(width, name)
Definition: cbs_vp9.c:257
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:303
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:53
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
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
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
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: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
double(* filter)(double white, double *buf, double half_amplitude)
internal API functions
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
#define AV_CH_LAYOUT_MONO
for(j=16;j >0;--j)
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:557
static double white_filter(double white, double *buf, double ha)