FFmpeg
af_vibrato.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
8  * License 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 GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/opt.h"
22 #include "avfilter.h"
23 #include "internal.h"
24 #include "audio.h"
25 #include "generate_wave_table.h"
26 
27 typedef struct VibratoContext {
28  const AVClass *class;
29  double freq;
30  double depth;
31  int channels;
32 
33  double **buf;
34  int buf_index;
35  int buf_size;
36 
37  double *wave_table;
41 
42 #define OFFSET(x) offsetof(VibratoContext, x)
43 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
44 
45 static const AVOption vibrato_options[] = {
46  { "f", "set frequency in hertz", OFFSET(freq), AV_OPT_TYPE_DOUBLE, {.dbl = 5.0}, 0.1, 20000.0, FLAGS },
47  { "d", "set depth as percentage", OFFSET(depth), AV_OPT_TYPE_DOUBLE, {.dbl = 0.5}, 0.00, 1.0, FLAGS },
48  { NULL }
49 };
50 
51 AVFILTER_DEFINE_CLASS(vibrato);
52 
54 {
55  AVFilterContext *ctx = inlink->dst;
56  VibratoContext *s = ctx->priv;
57  AVFilterLink *outlink = ctx->outputs[0];
58  AVFrame *out;
59  int n, c;
60  const double *src;
61  double *dst;
62 
63  if (av_frame_is_writable(in)) {
64  out = in;
65  } else {
66  out = ff_get_audio_buffer(outlink, in->nb_samples);
67  if (!out) {
68  av_frame_free(&in);
69  return AVERROR(ENOMEM);
70  }
72  }
73 
74  for (n = 0; n < in->nb_samples; n++) {
75  double integer, decimal;
76  decimal = modf(s->depth * s->wave_table[s->wave_table_index], &integer);
77 
78  s->wave_table_index++;
79  if (s->wave_table_index >= s->wave_table_size)
80  s->wave_table_index -= s->wave_table_size;
81 
82  for (c = 0; c < inlink->ch_layout.nb_channels; c++) {
83  int samp1_index, samp2_index;
84  double *buf;
85  double this_samp;
86 
87  src = (const double *)in->extended_data[c];
88  dst = (double *)out->extended_data[c];
89  buf = s->buf[c];
90 
91  samp1_index = s->buf_index + integer;
92  if (samp1_index >= s->buf_size)
93  samp1_index -= s->buf_size;
94  samp2_index = samp1_index + 1;
95  if (samp2_index >= s->buf_size)
96  samp2_index -= s->buf_size;
97 
98  this_samp = src[n];
99  dst[n] = buf[samp1_index] + (decimal * (buf[samp2_index] - buf[samp1_index]));
100  buf[s->buf_index] = this_samp;
101  }
102  s->buf_index++;
103  if (s->buf_index >= s->buf_size)
104  s->buf_index -= s->buf_size;
105  }
106 
107  if (in != out)
108  av_frame_free(&in);
109 
110  return ff_filter_frame(outlink, out);
111 }
112 
114 {
115  VibratoContext *s = ctx->priv;
116  int c;
117 
118  av_freep(&s->wave_table);
119  for (c = 0; c < s->channels; c++)
120  av_freep(&s->buf[c]);
121  av_freep(&s->buf);
122 }
123 
125 {
126  int c;
127  AVFilterContext *ctx = inlink->dst;
128  VibratoContext *s = ctx->priv;
129 
130  s->buf = av_calloc(inlink->ch_layout.nb_channels, sizeof(*s->buf));
131  if (!s->buf)
132  return AVERROR(ENOMEM);
133  s->channels = inlink->ch_layout.nb_channels;
134  s->buf_size = lrint(inlink->sample_rate * 0.005 + 0.5);
135  for (c = 0; c < s->channels; c++) {
136  s->buf[c] = av_malloc_array(s->buf_size, sizeof(*s->buf[c]));
137  if (!s->buf[c])
138  return AVERROR(ENOMEM);
139  }
140  s->buf_index = 0;
141 
142  s->wave_table_size = lrint(inlink->sample_rate / s->freq + 0.5);
143  s->wave_table = av_malloc_array(s->wave_table_size, sizeof(*s->wave_table));
144  if (!s->wave_table)
145  return AVERROR(ENOMEM);
146  ff_generate_wave_table(WAVE_SIN, AV_SAMPLE_FMT_DBL, s->wave_table, s->wave_table_size, 0.0, s->buf_size - 1, 3.0 * M_PI_2);
147  s->wave_table_index = 0;
148 
149  return 0;
150 }
151 
153  {
154  .name = "default",
155  .type = AVMEDIA_TYPE_AUDIO,
156  .config_props = config_input,
157  .filter_frame = filter_frame,
158  },
159 };
160 
162  {
163  .name = "default",
164  .type = AVMEDIA_TYPE_AUDIO,
165  },
166 };
167 
169  .name = "vibrato",
170  .description = NULL_IF_CONFIG_SMALL("Apply vibrato effect."),
171  .priv_size = sizeof(VibratoContext),
172  .priv_class = &vibrato_class,
173  .uninit = uninit,
178 };
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:100
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
out
FILE * out
Definition: movenc.c:54
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:999
VibratoContext::wave_table
double * wave_table
Definition: af_vibrato.c:37
FILTER_SINGLE_SAMPLEFMT
#define FILTER_SINGLE_SAMPLEFMT(sample_fmt_)
Definition: internal.h:183
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:116
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
M_PI_2
#define M_PI_2
Definition: mathematics.h:55
VibratoContext::freq
double freq
Definition: af_vibrato.c:29
AVOption
AVOption.
Definition: opt.h:251
integer
int integer
Definition: swresample_internal.h:37
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:175
VibratoContext
Definition: af_vibrato.c:27
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_vibrato.c:53
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_vibrato.c:113
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:49
lrint
#define lrint
Definition: tablegen.h:53
av_cold
#define av_cold
Definition: attributes.h:90
avfilter_af_vibrato_inputs
static const AVFilterPad avfilter_af_vibrato_inputs[]
Definition: af_vibrato.c:152
s
#define s(width, name)
Definition: cbs_vp9.c:256
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:227
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ctx
AVFormatContext * ctx
Definition: movenc.c:48
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:190
WAVE_SIN
@ WAVE_SIN
Definition: generate_wave_table.h:25
ff_af_vibrato
const AVFilter ff_af_vibrato
Definition: af_vibrato.c:168
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
VibratoContext::buf
double ** buf
Definition: af_vibrato.c:33
NULL
#define NULL
Definition: coverity.c:32
av_frame_copy_props
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:603
VibratoContext::wave_table_size
int wave_table_size
Definition: af_vibrato.c:39
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_vibrato.c:124
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(vibrato)
FLAGS
#define FLAGS
Definition: af_vibrato.c:43
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
ff_generate_wave_table
void ff_generate_wave_table(enum WaveType wave_type, enum AVSampleFormat sample_fmt, void *table, int table_size, double min, double max, double phase)
Definition: generate_wave_table.c:24
VibratoContext::buf_index
int buf_index
Definition: af_vibrato.c:34
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_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:533
vibrato_options
static const AVOption vibrato_options[]
Definition: af_vibrato.c:45
avfilter_af_vibrato_outputs
static const AVFilterPad avfilter_af_vibrato_outputs[]
Definition: af_vibrato.c:161
VibratoContext::depth
double depth
Definition: af_vibrato.c:30
internal.h
AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:152
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:405
AVFrame::extended_data
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:386
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:31
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:55
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:272
AVFilter
Filter definition.
Definition: avfilter.h:171
VibratoContext::buf_size
int buf_size
Definition: af_vibrato.c:35
generate_wave_table.h
avfilter.h
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:67
AVFilterContext
An instance of a filter.
Definition: avfilter.h:408
audio.h
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:191
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
VibratoContext::wave_table_index
int wave_table_index
Definition: af_vibrato.c:38
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
VibratoContext::channels
int channels
Definition: af_vibrato.c:31
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:61
OFFSET
#define OFFSET(x)
Definition: af_vibrato.c:42