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/channel_layout.h"
22 #include "libavutil/opt.h"
23 #include "audio.h"
24 #include "avfilter.h"
25 #include "filters.h"
26 #include "internal.h"
27 #include "libavutil/lfg.h"
28 #include "libavutil/random_seed.h"
29 
30 typedef struct ANoiseSrcContext {
31  const AVClass *class;
32  int sample_rate;
33  double amplitude;
34  int64_t duration;
35  int color;
36  int64_t seed;
37  int nb_samples;
38 
39  int64_t pts;
40  int infinite;
41  double (*filter)(double white, double *buf, double half_amplitude);
42  double buf[7];
43  AVLFG c;
44 } ANoiseSrcContext;
45 
46 enum NoiseMode {
47  NM_WHITE,
48  NM_PINK,
49  NM_BROWN,
50  NM_BLUE,
51  NM_VIOLET,
52  NM_VELVET,
53  NM_NB
54 };
55 
56 #define OFFSET(x) offsetof(ANoiseSrcContext, x)
57 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
58 
59 static const AVOption anoisesrc_options[] = {
60  { "sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
61  { "r", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 15, INT_MAX, FLAGS },
62  { "amplitude", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
63  { "a", "set amplitude", OFFSET(amplitude), AV_OPT_TYPE_DOUBLE, {.dbl = 1.}, 0., 1., FLAGS },
64  { "duration", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
65  { "d", "set duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, FLAGS },
66  { "color", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
67  { "colour", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
68  { "c", "set noise color", OFFSET(color), AV_OPT_TYPE_INT, {.i64 = 0}, 0, NM_NB - 1, FLAGS, "color" },
69  { "white", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_WHITE}, 0, 0, FLAGS, "color" },
70  { "pink", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_PINK}, 0, 0, FLAGS, "color" },
71  { "brown", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BROWN}, 0, 0, FLAGS, "color" },
72  { "blue", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_BLUE}, 0, 0, FLAGS, "color" },
73  { "violet", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_VIOLET}, 0, 0, FLAGS, "color" },
74  { "velvet", 0, 0, AV_OPT_TYPE_CONST, {.i64 = NM_VELVET}, 0, 0, FLAGS, "color" },
75  { "seed", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
76  { "s", "set random seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, FLAGS },
77  { "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
78  { "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 1, INT_MAX, FLAGS },
79  {NULL}
80 };
81 
82 AVFILTER_DEFINE_CLASS(anoisesrc);
83 
84 static av_cold int query_formats(AVFilterContext *ctx)
85 {
86  ANoiseSrcContext *s = ctx->priv;
87  static const int64_t chlayouts[] = { AV_CH_LAYOUT_MONO, -1 };
88  int sample_rates[] = { s->sample_rate, -1 };
89  static const enum AVSampleFormat sample_fmts[] = {
90  AV_SAMPLE_FMT_DBL,
91  AV_SAMPLE_FMT_NONE
92  };
93  int ret = ff_set_common_formats_from_list(ctx, sample_fmts);
94  if (ret < 0)
95  return ret;
96 
97  ret = ff_set_common_channel_layouts_from_list(ctx, chlayouts);
98  if (ret < 0)
99  return ret;
100 
101  return ff_set_common_samplerates_from_list(ctx, sample_rates);
102 }
103 
104 static double white_filter(double white, double *buf, double ha)
105 {
106  return white;
107 }
108 
109 static double pink_filter(double white, double *buf, double ha)
110 {
111  double pink;
112 
113  /* http://www.musicdsp.org/files/pink.txt */
114  buf[0] = 0.99886 * buf[0] + white * 0.0555179;
115  buf[1] = 0.99332 * buf[1] + white * 0.0750759;
116  buf[2] = 0.96900 * buf[2] + white * 0.1538520;
117  buf[3] = 0.86650 * buf[3] + white * 0.3104856;
118  buf[4] = 0.55000 * buf[4] + white * 0.5329522;
119  buf[5] = -0.7616 * buf[5] - white * 0.0168980;
120  pink = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
121  buf[6] = white * 0.115926;
122  return pink * 0.11;
123 }
124 
125 static double blue_filter(double white, double *buf, double ha)
126 {
127  double blue;
128 
129  /* Same as pink_filter but subtract the offsets rather than add */
130  buf[0] = 0.0555179 * white - 0.99886 * buf[0];
131  buf[1] = 0.0750759 * white - 0.99332 * buf[1];
132  buf[2] = 0.1538520 * white - 0.96900 * buf[2];
133  buf[3] = 0.3104856 * white - 0.86650 * buf[3];
134  buf[4] = 0.5329522 * white - 0.55000 * buf[4];
135  buf[5] = -0.016898 * white + 0.76160 * buf[5];
136  blue = buf[0] + buf[1] + buf[2] + buf[3] + buf[4] + buf[5] + buf[6] + white * 0.5362;
137  buf[6] = white * 0.115926;
138  return blue * 0.11;
139 }
140 
141 static double brown_filter(double white, double *buf, double ha)
142 {
143  double brown;
144 
145  brown = ((0.02 * white) + buf[0]) / 1.02;
146  buf[0] = brown;
147  return brown * 3.5;
148 }
149 
150 static double violet_filter(double white, double *buf, double ha)
151 {
152  double violet;
153 
154  violet = ((0.02 * white) - buf[0]) / 1.02;
155  buf[0] = violet;
156  return violet * 3.5;
157 }
158 
159 static double velvet_filter(double white, double *buf, double ha)
160 {
161  return 2. * ha * ((white > ha) - (white < -ha));
162 }
163 
164 static av_cold int config_props(AVFilterLink *outlink)
165 {
166  AVFilterContext *ctx = outlink->src;
167  ANoiseSrcContext *s = ctx->priv;
168 
169  if (s->seed == -1)
170  s->seed = av_get_random_seed();
171  av_lfg_init(&s->c, s->seed);
172 
173  if (s->duration == 0)
174  s->infinite = 1;
175  s->duration = av_rescale(s->duration, s->sample_rate, AV_TIME_BASE);
176 
177  switch (s->color) {
178  case NM_WHITE: s->filter = white_filter; break;
179  case NM_PINK: s->filter = pink_filter; break;
180  case NM_BROWN: s->filter = brown_filter; break;
181  case NM_BLUE: s->filter = blue_filter; break;
182  case NM_VIOLET: s->filter = violet_filter; break;
183  case NM_VELVET: s->filter = velvet_filter; break;
184  }
185 
186  return 0;
187 }
188 
189 static int activate(AVFilterContext *ctx)
190 {
191  AVFilterLink *outlink = ctx->outputs[0];
192  ANoiseSrcContext *s = ctx->priv;
193  AVFrame *frame;
194  int nb_samples, i;
195  double *dst;
196 
197  if (!ff_outlink_frame_wanted(outlink))
198  return FFERROR_NOT_READY;
199 
200  if (!s->infinite && s->duration <= 0) {
201  ff_outlink_set_status(outlink, AVERROR_EOF, s->pts);
202  return 0;
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, s->amplitude * 0.5);
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  .config_props = config_props,
232  },
233 };
234 
235 const AVFilter ff_asrc_anoisesrc = {
236  .name = "anoisesrc",
237  .description = NULL_IF_CONFIG_SMALL("Generate a noise audio signal."),
238  .query_formats = query_formats,
239  .priv_size = sizeof(ANoiseSrcContext),
240  .inputs = NULL,
241  .activate = activate,
242  FILTER_OUTPUTS(anoisesrc_outputs),
243  .priv_class = &anoisesrc_class,
244 };
velvet_filter
static double velvet_filter(double white, double *buf, double ha)
Definition: asrc_anoisesrc.c:159
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:88
NM_PINK
@ NM_PINK
Definition: asrc_anoisesrc.c:48
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:59
color
Definition: vf_paletteuse.c:587
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, double ha)
Definition: asrc_anoisesrc.c:150
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1019
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:948
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
FFERROR_NOT_READY
return FFERROR_NOT_READY
Definition: filter_design.txt:204
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:90
activate
static int activate(AVFilterContext *ctx)
Definition: asrc_anoisesrc.c:189
ff_set_common_samplerates_from_list
int ff_set_common_samplerates_from_list(AVFilterContext *ctx, const int *samplerates)
Equivalent to ff_set_common_samplerates(ctx, ff_make_format_list(samplerates))
Definition: formats.c:681
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AVOption
AVOption.
Definition: opt.h:247
ANoiseSrcContext::c
AVLFG c
Definition: asrc_anoisesrc.c:43
NoiseMode
NoiseMode
Definition: asrc_anoisesrc.c:46
AV_OPT_TYPE_DURATION
@ AV_OPT_TYPE_DURATION
Definition: opt.h:238
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
sample_rate
sample_rate
Definition: ffmpeg_filter.c:156
ff_set_common_channel_layouts_from_list
int ff_set_common_channel_layouts_from_list(AVFilterContext *ctx, const int64_t *fmts)
Equivalent to ff_set_common_channel_layouts(ctx, ff_make_format64_list(fmts))
Definition: formats.c:663
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
anoisesrc_outputs
static const AVFilterPad anoisesrc_outputs[]
Definition: asrc_anoisesrc.c:227
ANoiseSrcContext
Definition: asrc_anoisesrc.c:30
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
brown_filter
static double brown_filter(double white, double *buf, double ha)
Definition: asrc_anoisesrc.c:141
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(anoisesrc)
av_cold
#define av_cold
Definition: attributes.h:90
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
NM_WHITE
@ NM_WHITE
Definition: asrc_anoisesrc.c:47
duration
int64_t duration
Definition: movenc.c:64
ff_outlink_set_status
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
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:226
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
lfg.h
ff_set_common_formats_from_list
int ff_set_common_formats_from_list(AVFilterContext *ctx, const int *fmts)
Equivalent to ff_set_common_formats(ctx, ff_make_format_list(fmts))
Definition: formats.c:703
AV_OPT_TYPE_INT64
@ AV_OPT_TYPE_INT64
Definition: opt.h:225
filters.h
NM_VIOLET
@ NM_VIOLET
Definition: asrc_anoisesrc.c:51
ctx
AVFormatContext * ctx
Definition: movenc.c:48
NM_NB
@ NM_NB
Definition: asrc_anoisesrc.c:53
NM_BROWN
@ NM_BROWN
Definition: asrc_anoisesrc.c:49
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
ANoiseSrcContext::infinite
int infinite
Definition: asrc_anoisesrc.c:40
query_formats
static av_cold int query_formats(AVFilterContext *ctx)
Definition: asrc_anoisesrc.c:84
ANoiseSrcContext::amplitude
double amplitude
Definition: asrc_anoisesrc.c:33
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:117
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:164
ANoiseSrcContext::pts
int64_t pts
Definition: asrc_anoisesrc.c:39
NM_VELVET
@ NM_VELVET
Definition: asrc_anoisesrc.c:52
sample_rates
sample_rates
Definition: ffmpeg_filter.c:156
internal.h
i
int i
Definition: input.c:406
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:32
ANoiseSrcContext::filter
double(* filter)(double white, double *buf, double half_amplitude)
Definition: asrc_anoisesrc.c:41
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
OFFSET
#define OFFSET(x)
Definition: asrc_anoisesrc.c:56
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
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:128
NM_BLUE
@ NM_BLUE
Definition: asrc_anoisesrc.c:50
ANoiseSrcContext::color
int color
Definition: asrc_anoisesrc.c:35
AVFilter
Filter definition.
Definition: avfilter.h:149
ret
ret
Definition: filter_design.txt:187
white_filter
static double white_filter(double white, double *buf, double ha)
Definition: asrc_anoisesrc.c:104
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
FLAGS
#define FLAGS
Definition: asrc_anoisesrc.c:57
ANoiseSrcContext::seed
int64_t seed
Definition: asrc_anoisesrc.c:36
random_seed.h
ff_asrc_anoisesrc
const AVFilter ff_asrc_anoisesrc
Definition: asrc_anoisesrc.c:235
channel_layout.h
pink_filter
static double pink_filter(double white, double *buf, double ha)
Definition: asrc_anoisesrc.c:109
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
avfilter.h
ANoiseSrcContext::nb_samples
int nb_samples
Definition: asrc_anoisesrc.c:37
AVFilterContext
An instance of a filter.
Definition: avfilter.h:346
ANoiseSrcContext::buf
double buf[7]
Definition: asrc_anoisesrc.c:42
audio.h
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:153
ff_outlink_frame_wanted
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
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:64
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:233
blue_filter
static double blue_filter(double white, double *buf, double ha)
Definition: asrc_anoisesrc.c:125
ANoiseSrcContext::duration
int64_t duration
Definition: asrc_anoisesrc.c:34
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