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 "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;
33  int64_t duration;
34  int color;
35  int64_t seed;
37 
38  int64_t pts;
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:581
static double violet_filter(double white, double *buf, double ha)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:308
AVOption.
Definition: opt.h:248
Main libavfilter public API header.
static const AVOption anoisesrc_options[]
return FFERROR_NOT_READY
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)
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:1091
#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:401
AVFilter ff_asrc_anoisesrc
#define OFFSET(x)
#define AVERROR_EOF
End of file.
Definition: error.h:55
the definition of that something depends on the semantic of the filter The callback must examine the status of the filter s links and proceed accordingly The status of output links is stored in the status_in and status_out fields and tested by the ff_outlink_frame_wanted() function.If this function returns true
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:600
#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:153
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
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
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:322
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:723
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:588
int i
Definition: input.c:406
static double white_filter(double white, double *buf, double ha)