FFmpeg  4.0
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 "avutil.h"
28 #include "audio_fifo.h"
29 #include "common.h"
30 #include "fifo.h"
31 #include "mem.h"
32 #include "samplefmt.h"
33 
34 struct AVAudioFifo {
35  AVFifoBuffer **buf; /**< single buffer for interleaved, per-channel buffers for planar */
36  int nb_buffers; /**< number of buffers */
37  int nb_samples; /**< number of samples currently in the FIFO */
38  int allocated_samples; /**< current allocated size, in samples */
39 
40  int channels; /**< number of channels */
41  enum AVSampleFormat sample_fmt; /**< sample format */
42  int sample_size; /**< size, in bytes, of one sample in a buffer */
43 };
44 
46 {
47  if (af) {
48  if (af->buf) {
49  int i;
50  for (i = 0; i < af->nb_buffers; i++) {
51  av_fifo_freep(&af->buf[i]);
52  }
53  av_freep(&af->buf);
54  }
55  av_free(af);
56  }
57 }
58 
60  int nb_samples)
61 {
62  AVAudioFifo *af;
63  int buf_size, i;
64 
65  /* get channel buffer size (also validates parameters) */
66  if (av_samples_get_buffer_size(&buf_size, channels, nb_samples, sample_fmt, 1) < 0)
67  return NULL;
68 
69  af = av_mallocz(sizeof(*af));
70  if (!af)
71  return NULL;
72 
73  af->channels = channels;
74  af->sample_fmt = sample_fmt;
75  af->sample_size = buf_size / nb_samples;
76  af->nb_buffers = av_sample_fmt_is_planar(sample_fmt) ? channels : 1;
77 
78  af->buf = av_mallocz_array(af->nb_buffers, sizeof(*af->buf));
79  if (!af->buf)
80  goto error;
81 
82  for (i = 0; i < af->nb_buffers; i++) {
83  af->buf[i] = av_fifo_alloc(buf_size);
84  if (!af->buf[i])
85  goto error;
86  }
88 
89  return af;
90 
91 error:
93  return NULL;
94 }
95 
97 {
98  int i, ret, buf_size;
99 
100  if ((ret = av_samples_get_buffer_size(&buf_size, af->channels, nb_samples,
101  af->sample_fmt, 1)) < 0)
102  return ret;
103 
104  for (i = 0; i < af->nb_buffers; i++) {
105  if ((ret = av_fifo_realloc2(af->buf[i], buf_size)) < 0)
106  return ret;
107  }
109  return 0;
110 }
111 
113 {
114  int i, ret, size;
115 
116  /* automatically reallocate buffers if needed */
117  if (av_audio_fifo_space(af) < nb_samples) {
118  int current_size = av_audio_fifo_size(af);
119  /* check for integer overflow in new size calculation */
120  if (INT_MAX / 2 - current_size < nb_samples)
121  return AVERROR(EINVAL);
122  /* reallocate buffers */
123  if ((ret = av_audio_fifo_realloc(af, 2 * (current_size + nb_samples))) < 0)
124  return ret;
125  }
126 
127  size = nb_samples * af->sample_size;
128  for (i = 0; i < af->nb_buffers; i++) {
129  ret = av_fifo_generic_write(af->buf[i], data[i], size, NULL);
130  if (ret != size)
131  return AVERROR_BUG;
132  }
133  af->nb_samples += nb_samples;
134 
135  return nb_samples;
136 }
137 
139 {
140  int i, ret, size;
141 
142  if (nb_samples < 0)
143  return AVERROR(EINVAL);
144  nb_samples = FFMIN(nb_samples, af->nb_samples);
145  if (!nb_samples)
146  return 0;
147 
148  size = nb_samples * af->sample_size;
149  for (i = 0; i < af->nb_buffers; i++) {
150  if ((ret = av_fifo_generic_peek(af->buf[i], data[i], size, NULL)) < 0)
151  return AVERROR_BUG;
152  }
153 
154  return nb_samples;
155 }
156 
158 {
159  int i, ret, size;
160 
161  if (offset < 0 || offset >= af->nb_samples)
162  return AVERROR(EINVAL);
163  if (nb_samples < 0)
164  return AVERROR(EINVAL);
165  nb_samples = FFMIN(nb_samples, af->nb_samples);
166  if (!nb_samples)
167  return 0;
168  if (offset > af->nb_samples - nb_samples)
169  return AVERROR(EINVAL);
170 
171  offset *= af->sample_size;
172  size = nb_samples * af->sample_size;
173  for (i = 0; i < af->nb_buffers; i++) {
174  if ((ret = av_fifo_generic_peek_at(af->buf[i], data[i], offset, size, NULL)) < 0)
175  return AVERROR_BUG;
176  }
177 
178  return nb_samples;
179 }
180 
182 {
183  int i, size;
184 
185  if (nb_samples < 0)
186  return AVERROR(EINVAL);
187  nb_samples = FFMIN(nb_samples, af->nb_samples);
188  if (!nb_samples)
189  return 0;
190 
191  size = nb_samples * af->sample_size;
192  for (i = 0; i < af->nb_buffers; i++) {
193  if (av_fifo_generic_read(af->buf[i], data[i], size, NULL) < 0)
194  return AVERROR_BUG;
195  }
196  af->nb_samples -= nb_samples;
197 
198  return nb_samples;
199 }
200 
202 {
203  int i, size;
204 
205  if (nb_samples < 0)
206  return AVERROR(EINVAL);
207  nb_samples = FFMIN(nb_samples, af->nb_samples);
208 
209  if (nb_samples) {
210  size = nb_samples * af->sample_size;
211  for (i = 0; i < af->nb_buffers; i++)
212  av_fifo_drain(af->buf[i], size);
213  af->nb_samples -= nb_samples;
214  }
215  return 0;
216 }
217 
219 {
220  int i;
221 
222  for (i = 0; i < af->nb_buffers; i++)
223  av_fifo_reset(af->buf[i]);
224 
225  af->nb_samples = 0;
226 }
227 
229 {
230  return af->nb_samples;
231 }
232 
234 {
235  return af->allocated_samples - af->nb_samples;
236 }
#define NULL
Definition: coverity.c:32
AVAudioFifo * av_audio_fifo_alloc(enum AVSampleFormat sample_fmt, int channels, int nb_samples)
Allocate an AVAudioFifo.
Definition: audio_fifo.c:59
int av_audio_fifo_read(AVAudioFifo *af, void **data, int nb_samples)
Read data from an AVAudioFifo.
Definition: audio_fifo.c:181
int size
Memory handling functions.
channels
Definition: aptx.c:30
void av_audio_fifo_free(AVAudioFifo *af)
Free an AVAudioFifo.
Definition: audio_fifo.c:45
Convenience header that includes libavutil&#39;s core.
int av_fifo_generic_peek(AVFifoBuffer *f, void *dest, int buf_size, void(*func)(void *, void *, int))
Feed data from an AVFifoBuffer to a user-supplied callback.
Definition: fifo.c:189
int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int(*func)(void *, void *, int))
Feed data from a user-supplied callback to an AVFifoBuffer.
Definition: fifo.c:122
enum AVSampleFormat sample_fmt
sample format
Definition: audio_fifo.c:41
int allocated_samples
current allocated size, in samples
Definition: audio_fifo.c:38
const char data[16]
Definition: mxf.c:90
int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt)
Check if the sample format is planar.
Definition: samplefmt.c:112
int av_audio_fifo_space(AVAudioFifo *af)
Get the current number of samples in the AVAudioFifo available for writing.
Definition: audio_fifo.c:233
#define AVERROR(e)
Definition: error.h:43
int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size, void(*func)(void *, void *, int))
Feed data from an AVFifoBuffer to a user-supplied callback.
Definition: fifo.c:213
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
Context for an Audio FIFO Buffer.
Definition: audio_fifo.c:34
int nb_buffers
number of buffers
Definition: audio_fifo.c:36
int av_audio_fifo_size(AVAudioFifo *af)
Get the current number of samples in the AVAudioFifo available for reading.
Definition: audio_fifo.c:228
int av_audio_fifo_realloc(AVAudioFifo *af, int nb_samples)
Reallocate an AVAudioFifo.
Definition: audio_fifo.c:96
#define FFMIN(a, b)
Definition: common.h:96
AVFifoBuffer ** buf
single buffer for interleaved, per-channel buffers for planar
Definition: audio_fifo.c:35
static void error(const char *err)
int nb_samples
number of samples currently in the FIFO
Definition: audio_fifo.c:37
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
int av_fifo_generic_peek_at(AVFifoBuffer *f, void *dest, int offset, int buf_size, void(*func)(void *, void *, int))
Feed data at specific position from an AVFifoBuffer to a user-supplied callback.
Definition: fifo.c:151
int av_fifo_realloc2(AVFifoBuffer *f, unsigned int new_size)
Resize an AVFifoBuffer.
Definition: fifo.c:87
int channels
number of channels
Definition: audio_fifo.c:40
a very simple circular buffer FIFO implementation
#define AVERROR_BUG
Internal bug, also see AVERROR_BUG2.
Definition: error.h:50
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:119
int sample_size
size, in bytes, of one sample in a buffer
Definition: audio_fifo.c:42
int av_audio_fifo_write(AVAudioFifo *af, void **data, int nb_samples)
Write data to an AVAudioFifo.
Definition: audio_fifo.c:112
int av_audio_fifo_drain(AVAudioFifo *af, int nb_samples)
Drain data from an AVAudioFifo.
Definition: audio_fifo.c:201
common internal and external API header
#define av_free(p)
Audio FIFO Buffer.
AVFifoBuffer * av_fifo_alloc(unsigned int size)
Initialize an AVFifoBuffer.
Definition: fifo.c:43
int av_audio_fifo_peek(AVAudioFifo *af, void **data, int nb_samples)
Peek data from an AVAudioFifo.
Definition: audio_fifo.c:138
#define av_freep(p)
void av_fifo_freep(AVFifoBuffer **f)
Free an AVFifoBuffer and reset pointer to NULL.
Definition: fifo.c:63
void av_fifo_reset(AVFifoBuffer *f)
Reset the AVFifoBuffer to the state right after av_fifo_alloc, in particular it is emptied...
Definition: fifo.c:71
void av_fifo_drain(AVFifoBuffer *f, int size)
Discard data from the FIFO.
Definition: fifo.c:233
int av_audio_fifo_peek_at(AVAudioFifo *af, void **data, int nb_samples, int offset)
Peek data from an AVAudioFifo.
Definition: audio_fifo.c:157
void * av_mallocz_array(size_t nmemb, size_t size)
Allocate a memory block for an array with av_mallocz().
Definition: mem.c:191
void av_audio_fifo_reset(AVAudioFifo *af)
Reset the AVAudioFifo buffer.
Definition: audio_fifo.c:218