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 "audio.h"
20 #include "avfilter.h"
21 #include "internal.h"
22 
23 typedef struct ADerivativeContext {
24  const AVClass *class;
26  void (*filter)(void **dst, void **prv, const void **src,
27  int nb_samples, int channels);
29 
30 #define DERIVATIVE(name, type) \
31 static void aderivative_## name ##p(void **d, void **p, const void **s, \
32  int nb_samples, int channels) \
33 { \
34  int n, c; \
35  \
36  for (c = 0; c < channels; c++) { \
37  const type *src = s[c]; \
38  type *dst = d[c]; \
39  type *prv = p[c]; \
40  \
41  for (n = 0; n < nb_samples; n++) { \
42  const type current = src[n]; \
43  \
44  dst[n] = current - prv[0]; \
45  prv[0] = current; \
46  } \
47  } \
48 }
49 
50 DERIVATIVE(flt, float)
51 DERIVATIVE(dbl, double)
52 DERIVATIVE(s16, int16_t)
53 DERIVATIVE(s32, int32_t)
54 
55 #define INTEGRAL(name, type) \
56 static void aintegral_## name ##p(void **d, void **p, const void **s, \
57  int nb_samples, int channels) \
58 { \
59  int n, c; \
60  \
61  for (c = 0; c < channels; c++) { \
62  const type *src = s[c]; \
63  type *dst = d[c]; \
64  type *prv = p[c]; \
65  \
66  for (n = 0; n < nb_samples; n++) { \
67  const type current = src[n]; \
68  \
69  dst[n] = current + prv[0]; \
70  prv[0] = dst[n]; \
71  } \
72  } \
73 }
74 
75 INTEGRAL(flt, float)
76 INTEGRAL(dbl, double)
77 
79 {
80  AVFilterContext *ctx = inlink->dst;
81  ADerivativeContext *s = ctx->priv;
82 
83  switch (inlink->format) {
84  case AV_SAMPLE_FMT_FLTP: s->filter = aderivative_fltp; break;
85  case AV_SAMPLE_FMT_DBLP: s->filter = aderivative_dblp; break;
86  case AV_SAMPLE_FMT_S32P: s->filter = aderivative_s32p; break;
87  case AV_SAMPLE_FMT_S16P: s->filter = aderivative_s16p; break;
88  }
89 
90  if (strcmp(ctx->filter->name, "aintegral"))
91  return 0;
92 
93  switch (inlink->format) {
94  case AV_SAMPLE_FMT_FLTP: s->filter = aintegral_fltp; break;
95  case AV_SAMPLE_FMT_DBLP: s->filter = aintegral_dblp; break;
96  }
97 
98  return 0;
99 }
100 
102 {
103  AVFilterContext *ctx = inlink->dst;
104  ADerivativeContext *s = ctx->priv;
105  AVFilterLink *outlink = ctx->outputs[0];
106  AVFrame *out = ff_get_audio_buffer(outlink, in->nb_samples);
107 
108  if (!out) {
109  av_frame_free(&in);
110  return AVERROR(ENOMEM);
111  }
113 
114  if (!s->prev) {
115  s->prev = ff_get_audio_buffer(inlink, 1);
116  if (!s->prev) {
117  av_frame_free(&in);
118  return AVERROR(ENOMEM);
119  }
120  }
121 
122  s->filter((void **)out->extended_data, (void **)s->prev->extended_data, (const void **)in->extended_data,
123  in->nb_samples, in->channels);
124 
125  av_frame_free(&in);
126  return ff_filter_frame(outlink, out);
127 }
128 
130 {
131  ADerivativeContext *s = ctx->priv;
132 
133  av_frame_free(&s->prev);
134 }
135 
136 static const AVFilterPad aderivative_inputs[] = {
137  {
138  .name = "default",
139  .type = AVMEDIA_TYPE_AUDIO,
140  .filter_frame = filter_frame,
141  .config_props = config_input,
142  },
143 };
144 
146  {
147  .name = "default",
148  .type = AVMEDIA_TYPE_AUDIO,
149  },
150 };
151 
153  .name = "aderivative",
154  .description = NULL_IF_CONFIG_SMALL("Compute derivative of input audio."),
155  .priv_size = sizeof(ADerivativeContext),
156  .uninit = uninit,
161 };
162 
164  .name = "aintegral",
165  .description = NULL_IF_CONFIG_SMALL("Compute integral of input audio."),
166  .priv_size = sizeof(ADerivativeContext),
167  .uninit = uninit,
171 };
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
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:69
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
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:1018
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:112
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AV_SAMPLE_FMT_S32P
@ AV_SAMPLE_FMT_S32P
signed 32 bits, planar
Definition: samplefmt.h:68
ADerivativeContext::filter
void(* filter)(void **dst, void **prv, const void **src, int nb_samples, int channels)
Definition: af_aderivative.c:26
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
aderivative_inputs
static const AVFilterPad aderivative_inputs[]
Definition: af_aderivative.c:136
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
av_cold
#define av_cold
Definition: attributes.h:90
ff_af_aintegral
const AVFilter ff_af_aintegral
Definition: af_aderivative.c:163
s
#define s(width, name)
Definition: cbs_vp9.c:257
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_aderivative.c:101
AVFrame::channels
int channels
number of audio channels, only used for audio.
Definition: frame.h:592
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_aderivative.c:78
ctx
AVFormatContext * ctx
Definition: movenc.c:48
channels
channels
Definition: aptx.h:33
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:191
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
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:537
src
#define src
Definition: vp8dsp.c:255
ADerivativeContext::prev
AVFrame * prev
Definition: af_aderivative.c:25
INTEGRAL
#define INTEGRAL(name, type)
Definition: af_aderivative.c:55
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:152
AV_SAMPLE_FMT_S16P
@ AV_SAMPLE_FMT_S16P
signed 16 bits, planar
Definition: samplefmt.h:67
internal.h
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:369
AVFrame::extended_data
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:350
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_aderivative.c:129
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
AVFilter
Filter definition.
Definition: avfilter.h:149
avfilter.h
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:70
AVFilterContext
An instance of a filter.
Definition: avfilter.h:386
audio.h
aderivative_outputs
static const AVFilterPad aderivative_outputs[]
Definition: af_aderivative.c:145
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:192
DERIVATIVE
#define DERIVATIVE(name, type)
Definition: af_aderivative.c:30
int32_t
int32_t
Definition: audioconvert.c:56
ADerivativeContext
Definition: af_aderivative.c:23
FILTER_SAMPLEFMTS
#define FILTER_SAMPLEFMTS(...)
Definition: internal.h:179