FFmpeg
af_aderivative.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "libavutil/opt.h"
20 #include "audio.h"
21 #include "avfilter.h"
22 #include "internal.h"
23 
24 typedef struct ADerivativeContext {
25  const AVClass *class;
27  void (*filter)(void **dst, void **prv, const void **src,
28  int nb_samples, int channels);
30 
31 #define DERIVATIVE(name, type) \
32 static void aderivative_## name ##p(void **d, void **p, const void **s, \
33  int nb_samples, int channels) \
34 { \
35  int n, c; \
36  \
37  for (c = 0; c < channels; c++) { \
38  const type *src = s[c]; \
39  type *dst = d[c]; \
40  type *prv = p[c]; \
41  \
42  for (n = 0; n < nb_samples; n++) { \
43  const type current = src[n]; \
44  \
45  dst[n] = current - prv[0]; \
46  prv[0] = current; \
47  } \
48  } \
49 }
50 
51 DERIVATIVE(flt, float)
52 DERIVATIVE(dbl, double)
53 DERIVATIVE(s16, int16_t)
54 DERIVATIVE(s32, int32_t)
55 
56 #define INTEGRAL(name, type) \
57 static void aintegral_## name ##p(void **d, void **p, const void **s, \
58  int nb_samples, int channels) \
59 { \
60  int n, c; \
61  \
62  for (c = 0; c < channels; c++) { \
63  const type *src = s[c]; \
64  type *dst = d[c]; \
65  type *prv = p[c]; \
66  \
67  for (n = 0; n < nb_samples; n++) { \
68  const type current = src[n]; \
69  \
70  dst[n] = current + prv[0]; \
71  prv[0] = dst[n]; \
72  } \
73  } \
74 }
75 
76 INTEGRAL(flt, float)
77 INTEGRAL(dbl, double)
78 
80 {
81  AVFilterContext *ctx = inlink->dst;
82  ADerivativeContext *s = ctx->priv;
83 
84  switch (inlink->format) {
85  case AV_SAMPLE_FMT_FLTP: s->filter = aderivative_fltp; break;
86  case AV_SAMPLE_FMT_DBLP: s->filter = aderivative_dblp; break;
87  case AV_SAMPLE_FMT_S32P: s->filter = aderivative_s32p; break;
88  case AV_SAMPLE_FMT_S16P: s->filter = aderivative_s16p; break;
89  }
90 
91  if (strcmp(ctx->filter->name, "aintegral"))
92  return 0;
93 
94  switch (inlink->format) {
95  case AV_SAMPLE_FMT_FLTP: s->filter = aintegral_fltp; break;
96  case AV_SAMPLE_FMT_DBLP: s->filter = aintegral_dblp; break;
97  }
98 
99  return 0;
100 }
101 
103 {
104  AVFilterContext *ctx = inlink->dst;
105  ADerivativeContext *s = ctx->priv;
106  AVFilterLink *outlink = ctx->outputs[0];
107  AVFrame *out;
108 
109  if (ctx->is_disabled) {
110  if (s->prev)
111  av_samples_set_silence(s->prev->extended_data, 0, 1,
112  s->prev->ch_layout.nb_channels,
113  s->prev->format);
114 
115  return ff_filter_frame(outlink, in);
116  }
117 
118  out = ff_get_audio_buffer(outlink, in->nb_samples);
119  if (!out) {
120  av_frame_free(&in);
121  return AVERROR(ENOMEM);
122  }
124 
125  if (!s->prev) {
126  s->prev = ff_get_audio_buffer(inlink, 1);
127  if (!s->prev) {
128  av_frame_free(&in);
129  return AVERROR(ENOMEM);
130  }
131  }
132 
133  s->filter((void **)out->extended_data, (void **)s->prev->extended_data, (const void **)in->extended_data,
134  in->nb_samples, in->ch_layout.nb_channels);
135 
136  av_frame_free(&in);
137  return ff_filter_frame(outlink, out);
138 }
139 
141 {
142  ADerivativeContext *s = ctx->priv;
143 
144  av_frame_free(&s->prev);
145 }
146 
147 static const AVFilterPad aderivative_inputs[] = {
148  {
149  .name = "default",
150  .type = AVMEDIA_TYPE_AUDIO,
151  .filter_frame = filter_frame,
152  .config_props = config_input,
153  },
154 };
155 
157  {
158  .name = "default",
159  .type = AVMEDIA_TYPE_AUDIO,
160  },
161 };
162 
163 static const AVOption aderivative_options[] = {
164  { NULL }
165 };
166 
167 AVFILTER_DEFINE_CLASS_EXT(aderivative, "aderivative/aintegral", aderivative_options);
168 
170  .name = "aderivative",
171  .description = NULL_IF_CONFIG_SMALL("Compute derivative of input audio."),
172  .priv_size = sizeof(ADerivativeContext),
173  .priv_class = &aderivative_class,
174  .uninit = uninit,
180 };
181 
183  .name = "aintegral",
184  .description = NULL_IF_CONFIG_SMALL("Compute integral of input audio."),
185  .priv_size = sizeof(ADerivativeContext),
186  .priv_class = &aderivative_class,
187  .uninit = uninit,
192 };
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
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:66
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
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
AVOption
AVOption.
Definition: opt.h:251
AV_SAMPLE_FMT_S32P
@ AV_SAMPLE_FMT_S32P
signed 32 bits, planar
Definition: samplefmt.h:65
ADerivativeContext::filter
void(* filter)(void **dst, void **prv, const void **src, int nb_samples, int channels)
Definition: af_aderivative.c:27
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:175
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:300
aderivative_options
static const AVOption aderivative_options[]
Definition: af_aderivative.c:163
AVFrame::ch_layout
AVChannelLayout ch_layout
Channel layout of the audio data.
Definition: frame.h:709
aderivative_inputs
static const AVFilterPad aderivative_inputs[]
Definition: af_aderivative.c:147
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:49
av_cold
#define av_cold
Definition: attributes.h:90
ff_af_aintegral
const AVFilter ff_af_aintegral
Definition: af_aderivative.c:182
s
#define s(width, name)
Definition: cbs_vp9.c:256
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_aderivative.c:102
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_aderivative.c:79
ctx
AVFormatContext * ctx
Definition: movenc.c:48
channels
channels
Definition: aptx.h:32
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:190
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
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
AVFILTER_DEFINE_CLASS_EXT
AVFILTER_DEFINE_CLASS_EXT(aderivative, "aderivative/aintegral", aderivative_options)
ADerivativeContext::prev
AVFrame * prev
Definition: af_aderivative.c:26
INTEGRAL
#define INTEGRAL(name, type)
Definition: af_aderivative.c:56
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
ff_af_aderivative
const AVFilter ff_af_aderivative
Definition: af_aderivative.c:169
AV_SAMPLE_FMT_S16P
@ AV_SAMPLE_FMT_S16P
signed 16 bits, planar
Definition: samplefmt.h:64
internal.h
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
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_aderivative.c:140
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:55
av_samples_set_silence
int av_samples_set_silence(uint8_t **audio_data, int offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)
Fill an audio buffer with silence.
Definition: samplefmt.c:246
AVFilter
Filter definition.
Definition: avfilter.h:171
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
aderivative_outputs
static const AVFilterPad aderivative_outputs[]
Definition: af_aderivative.c:156
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:191
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
DERIVATIVE
#define DERIVATIVE(name, type)
Definition: af_aderivative.c:31
int32_t
int32_t
Definition: audioconvert.c:56
AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
#define AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL
Same as AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, except that the filter will have its filter_frame() c...
Definition: avfilter.h:160
ADerivativeContext
Definition: af_aderivative.c:24
FILTER_SAMPLEFMTS
#define FILTER_SAMPLEFMTS(...)
Definition: internal.h:178