FFmpeg
audio_fifo.c
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1 /*
2  * Audio FIFO
3  * Copyright (c) 2012 Justin Ruggles <justin.ruggles@gmail.com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Audio FIFO
25  */
26 
27 #include <limits.h>
28 #include <stddef.h>
29 
30 #include "audio_fifo.h"
31 #include "error.h"
32 #include "fifo.h"
33 #include "macros.h"
34 #include "mem.h"
35 #include "samplefmt.h"
36 
37 struct AVAudioFifo {
38  AVFifo **buf; /**< single buffer for interleaved, per-channel buffers for planar */
39  int nb_buffers; /**< number of buffers */
40  int nb_samples; /**< number of samples currently in the FIFO */
41  int allocated_samples; /**< current allocated size, in samples */
42 
43  int channels; /**< number of channels */
44  enum AVSampleFormat sample_fmt; /**< sample format */
45  int sample_size; /**< size, in bytes, of one sample in a buffer */
46 };
47 
49 {
50  if (af) {
51  if (af->buf) {
52  int i;
53  for (i = 0; i < af->nb_buffers; i++) {
54  av_fifo_freep2(&af->buf[i]);
55  }
56  av_freep(&af->buf);
57  }
58  av_free(af);
59  }
60 }
61 
63  int nb_samples)
64 {
65  AVAudioFifo *af;
66  int buf_size, i;
67 
68  /* get channel buffer size (also validates parameters) */
69  if (av_samples_get_buffer_size(&buf_size, channels, nb_samples, sample_fmt, 1) < 0)
70  return NULL;
71 
72  af = av_mallocz(sizeof(*af));
73  if (!af)
74  return NULL;
75 
76  af->channels = channels;
77  af->sample_fmt = sample_fmt;
78  af->sample_size = buf_size / nb_samples;
79  af->nb_buffers = av_sample_fmt_is_planar(sample_fmt) ? channels : 1;
80 
81  af->buf = av_calloc(af->nb_buffers, sizeof(*af->buf));
82  if (!af->buf)
83  goto error;
84 
85  for (i = 0; i < af->nb_buffers; i++) {
86  af->buf[i] = av_fifo_alloc2(buf_size, 1, 0);
87  if (!af->buf[i])
88  goto error;
89  }
90  af->allocated_samples = nb_samples;
91 
92  return af;
93 
94 error:
96  return NULL;
97 }
98 
99 int av_audio_fifo_realloc(AVAudioFifo *af, int nb_samples)
100 {
101  const size_t cur_size = av_fifo_can_read (af->buf[0]) +
102  av_fifo_can_write(af->buf[0]);
103  int i, ret, buf_size;
104 
105  if ((ret = av_samples_get_buffer_size(&buf_size, af->channels, nb_samples,
106  af->sample_fmt, 1)) < 0)
107  return ret;
108 
109  if (buf_size > cur_size) {
110  for (i = 0; i < af->nb_buffers; i++) {
111  if ((ret = av_fifo_grow2(af->buf[i], buf_size - cur_size)) < 0)
112  return ret;
113  }
114  }
115  af->allocated_samples = nb_samples;
116  return 0;
117 }
118 
119 int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples)
120 {
121  int i, ret, size;
122 
123  /* automatically reallocate buffers if needed */
124  if (av_audio_fifo_space(af) < nb_samples) {
125  int current_size = av_audio_fifo_size(af);
126  /* check for integer overflow in new size calculation */
127  if (INT_MAX / 2 - current_size < nb_samples)
128  return AVERROR(EINVAL);
129  /* reallocate buffers */
130  if ((ret = av_audio_fifo_realloc(af, 2 * (current_size + nb_samples))) < 0)
131  return ret;
132  }
133 
134  size = nb_samples * af->sample_size;
135  for (i = 0; i < af->nb_buffers; i++) {
136  ret = av_fifo_write(af->buf[i], data[i], size);
137  if (ret < 0)
138  return AVERROR_BUG;
139  }
140  af->nb_samples += nb_samples;
141 
142  return nb_samples;
143 }
144 
145 int av_audio_fifo_peek(AVAudioFifo *af, void **data, int nb_samples)
146 {
147  return av_audio_fifo_peek_at(af, data, nb_samples, 0);
148 }
149 
150 int av_audio_fifo_peek_at(AVAudioFifo *af, void **data, int nb_samples, int offset)
151 {
152  int i, ret, size;
153 
154  if (offset < 0 || offset >= af->nb_samples)
155  return AVERROR(EINVAL);
156  if (nb_samples < 0)
157  return AVERROR(EINVAL);
158  nb_samples = FFMIN(nb_samples, af->nb_samples);
159  if (!nb_samples)
160  return 0;
161  if (offset > af->nb_samples - nb_samples)
162  return AVERROR(EINVAL);
163 
164  offset *= af->sample_size;
165  size = nb_samples * af->sample_size;
166  for (i = 0; i < af->nb_buffers; i++) {
167  if ((ret = av_fifo_peek(af->buf[i], data[i], size, offset)) < 0)
168  return AVERROR_BUG;
169  }
170 
171  return nb_samples;
172 }
173 
174 int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples)
175 {
176  int i, size;
177 
178  if (nb_samples < 0)
179  return AVERROR(EINVAL);
180  nb_samples = FFMIN(nb_samples, af->nb_samples);
181  if (!nb_samples)
182  return 0;
183 
184  size = nb_samples * af->sample_size;
185  for (i = 0; i < af->nb_buffers; i++) {
186  if (av_fifo_read(af->buf[i], data[i], size) < 0)
187  return AVERROR_BUG;
188  }
189  af->nb_samples -= nb_samples;
190 
191  return nb_samples;
192 }
193 
194 int av_audio_fifo_drain(AVAudioFifo *af, int nb_samples)
195 {
196  int i, size;
197 
198  if (nb_samples < 0)
199  return AVERROR(EINVAL);
200  nb_samples = FFMIN(nb_samples, af->nb_samples);
201 
202  if (nb_samples) {
203  size = nb_samples * af->sample_size;
204  for (i = 0; i < af->nb_buffers; i++)
205  av_fifo_drain2(af->buf[i], size);
206  af->nb_samples -= nb_samples;
207  }
208  return 0;
209 }
210 
212 {
213  int i;
214 
215  for (i = 0; i < af->nb_buffers; i++)
216  av_fifo_reset2(af->buf[i]);
217 
218  af->nb_samples = 0;
219 }
220 
222 {
223  return af->nb_samples;
224 }
225 
227 {
228  return af->allocated_samples - af->nb_samples;
229 }
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:31
av_audio_fifo_free
void av_audio_fifo_free(AVAudioFifo *af)
Free an AVAudioFifo.
Definition: audio_fifo.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
av_audio_fifo_realloc
int av_audio_fifo_realloc(AVAudioFifo *af, int nb_samples)
Reallocate an AVAudioFifo.
Definition: audio_fifo.c:99
av_fifo_can_read
size_t av_fifo_can_read(const AVFifo *f)
Definition: fifo.c:87
data
const char data[16]
Definition: mxf.c:146
av_fifo_reset2
void av_fifo_reset2(AVFifo *f)
Definition: fifo.c:280
av_fifo_read
int av_fifo_read(AVFifo *f, void *buf, size_t nb_elems)
Read data from a FIFO.
Definition: fifo.c:240
AVAudioFifo::nb_samples
int nb_samples
number of samples currently in the FIFO
Definition: audio_fifo.c:40
fifo.h
AVAudioFifo
Context for an Audio FIFO Buffer.
Definition: audio_fifo.c:37
av_audio_fifo_drain
int av_audio_fifo_drain(AVAudioFifo *af, int nb_samples)
Drain data from an AVAudioFifo.
Definition: audio_fifo.c:194
macros.h
samplefmt.h
AVAudioFifo::channels
int channels
number of channels
Definition: audio_fifo.c:43
AVAudioFifo::sample_size
int sample_size
size, in bytes, of one sample in a buffer
Definition: audio_fifo.c:45
av_audio_fifo_write
int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples)
Write data to an AVAudioFifo.
Definition: audio_fifo.c:119
av_sample_fmt_is_planar
int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt)
Check if the sample format is planar.
Definition: samplefmt.c:114
channels
channels
Definition: aptx.h:32
limits.h
av_fifo_can_write
size_t av_fifo_can_write(const AVFifo *f)
Definition: fifo.c:94
AVAudioFifo::buf
AVFifo ** buf
single buffer for interleaved, per-channel buffers for planar
Definition: audio_fifo.c:38
NULL
#define NULL
Definition: coverity.c:32
av_audio_fifo_alloc
AVAudioFifo * av_audio_fifo_alloc(enum AVSampleFormat sample_fmt, int channels, int nb_samples)
Allocate an AVAudioFifo.
Definition: audio_fifo.c:62
error.h
av_audio_fifo_peek_at
int av_audio_fifo_peek_at(AVAudioFifo *af, void **data, int nb_samples, int offset)
Peek data from an AVAudioFifo.
Definition: audio_fifo.c:150
AVFifo
Definition: fifo.c:35
av_fifo_peek
int av_fifo_peek(AVFifo *f, void *buf, size_t nb_elems, size_t offset)
Read data from a FIFO without modifying FIFO state.
Definition: fifo.c:255
size
int size
Definition: twinvq_data.h:10344
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
av_audio_fifo_size
int av_audio_fifo_size(AVAudioFifo *af)
Get the current number of samples in the AVAudioFifo available for reading.
Definition: audio_fifo.c:221
av_audio_fifo_read
int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples)
Read data from an AVAudioFifo.
Definition: audio_fifo.c:174
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
av_fifo_alloc2
AVFifo * av_fifo_alloc2(size_t nb_elems, size_t elem_size, unsigned int flags)
Allocate and initialize an AVFifo with a given element size.
Definition: fifo.c:47
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:264
audio_fifo.h
av_fifo_freep2
void av_fifo_freep2(AVFifo **f)
Free an AVFifo and reset pointer to NULL.
Definition: fifo.c:286
av_samples_get_buffer_size
int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)
Get the required buffer size for the given audio parameters.
Definition: samplefmt.c:121
av_calloc
void * av_calloc(size_t nmemb, size_t size)
Definition: mem.c:272
ret
ret
Definition: filter_design.txt:187
av_fifo_write
int av_fifo_write(AVFifo *f, const void *buf, size_t nb_elems)
Write data into a FIFO.
Definition: fifo.c:188
AVAudioFifo::sample_fmt
enum AVSampleFormat sample_fmt
sample format
Definition: audio_fifo.c:44
AVAudioFifo::allocated_samples
int allocated_samples
current allocated size, in samples
Definition: audio_fifo.c:41
mem.h
AVAudioFifo::nb_buffers
int nb_buffers
number of buffers
Definition: audio_fifo.c:39
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
av_audio_fifo_space
int av_audio_fifo_space(AVAudioFifo *af)
Get the current number of samples in the AVAudioFifo available for writing.
Definition: audio_fifo.c:226
AVERROR_BUG
#define AVERROR_BUG
Internal bug, also see AVERROR_BUG2.
Definition: error.h:52
av_audio_fifo_reset
void av_audio_fifo_reset(AVAudioFifo *af)
Reset the AVAudioFifo buffer.
Definition: audio_fifo.c:211
av_fifo_drain2
void av_fifo_drain2(AVFifo *f, size_t size)
Discard the specified amount of data from an AVFifo.
Definition: fifo.c:266
av_audio_fifo_peek
int av_audio_fifo_peek(AVAudioFifo *af, void **data, int nb_samples)
Peek data from an AVAudioFifo.
Definition: audio_fifo.c:145
av_fifo_grow2
int av_fifo_grow2(AVFifo *f, size_t inc)
Enlarge an AVFifo.
Definition: fifo.c:99