samplefmt.c
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1 /*
2  * This file is part of Libav.
3  *
4  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include "common.h"
20 #include "samplefmt.h"
21 
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 
26 typedef struct SampleFmtInfo {
27  const char *name;
28  int bits;
29  int planar;
32 
35  [AV_SAMPLE_FMT_U8] = { .name = "u8", .bits = 8, .planar = 0, .altform = AV_SAMPLE_FMT_U8P },
36  [AV_SAMPLE_FMT_S16] = { .name = "s16", .bits = 16, .planar = 0, .altform = AV_SAMPLE_FMT_S16P },
37  [AV_SAMPLE_FMT_S32] = { .name = "s32", .bits = 32, .planar = 0, .altform = AV_SAMPLE_FMT_S32P },
38  [AV_SAMPLE_FMT_FLT] = { .name = "flt", .bits = 32, .planar = 0, .altform = AV_SAMPLE_FMT_FLTP },
39  [AV_SAMPLE_FMT_DBL] = { .name = "dbl", .bits = 64, .planar = 0, .altform = AV_SAMPLE_FMT_DBLP },
40  [AV_SAMPLE_FMT_U8P] = { .name = "u8p", .bits = 8, .planar = 1, .altform = AV_SAMPLE_FMT_U8 },
41  [AV_SAMPLE_FMT_S16P] = { .name = "s16p", .bits = 16, .planar = 1, .altform = AV_SAMPLE_FMT_S16 },
42  [AV_SAMPLE_FMT_S32P] = { .name = "s32p", .bits = 32, .planar = 1, .altform = AV_SAMPLE_FMT_S32 },
43  [AV_SAMPLE_FMT_FLTP] = { .name = "fltp", .bits = 32, .planar = 1, .altform = AV_SAMPLE_FMT_FLT },
44  [AV_SAMPLE_FMT_DBLP] = { .name = "dblp", .bits = 64, .planar = 1, .altform = AV_SAMPLE_FMT_DBL },
45 };
46 
48 {
49  if (sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB)
50  return NULL;
51  return sample_fmt_info[sample_fmt].name;
52 }
53 
55 {
56  int i;
57 
58  for (i = 0; i < AV_SAMPLE_FMT_NB; i++)
59  if (!strcmp(sample_fmt_info[i].name, name))
60  return i;
61  return AV_SAMPLE_FMT_NONE;
62 }
63 
65 {
66  if (sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB)
67  return AV_SAMPLE_FMT_NONE;
68  if (sample_fmt_info[sample_fmt].planar)
69  return sample_fmt_info[sample_fmt].altform;
70  return sample_fmt;
71 }
72 
74 {
75  if (sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB)
76  return AV_SAMPLE_FMT_NONE;
77  if (sample_fmt_info[sample_fmt].planar)
78  return sample_fmt;
79  return sample_fmt_info[sample_fmt].altform;
80 }
81 
82 char *av_get_sample_fmt_string (char *buf, int buf_size, enum AVSampleFormat sample_fmt)
83 {
84  /* print header */
85  if (sample_fmt < 0)
86  snprintf(buf, buf_size, "name " " depth");
87  else if (sample_fmt < AV_SAMPLE_FMT_NB) {
88  SampleFmtInfo info = sample_fmt_info[sample_fmt];
89  snprintf (buf, buf_size, "%-6s" " %2d ", info.name, info.bits);
90  }
91 
92  return buf;
93 }
94 
96 {
97  return sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB ?
98  0 : sample_fmt_info[sample_fmt].bits >> 3;
99 }
100 
102 {
103  if (sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB)
104  return 0;
105  return sample_fmt_info[sample_fmt].planar;
106 }
107 
109  enum AVSampleFormat sample_fmt, int align)
110 {
111  int line_size;
112  int sample_size = av_get_bytes_per_sample(sample_fmt);
113  int planar = av_sample_fmt_is_planar(sample_fmt);
114 
115  /* validate parameter ranges */
116  if (!sample_size || nb_samples <= 0 || nb_channels <= 0)
117  return AVERROR(EINVAL);
118 
119  /* auto-select alignment if not specified */
120  if (!align) {
121  if (nb_samples > INT_MAX - 31)
122  return AVERROR(EINVAL);
123  align = 1;
124  nb_samples = FFALIGN(nb_samples, 32);
125  }
126 
127  /* check for integer overflow */
128  if (nb_channels > INT_MAX / align ||
129  (int64_t)nb_channels * nb_samples > (INT_MAX - (align * nb_channels)) / sample_size)
130  return AVERROR(EINVAL);
131 
132  line_size = planar ? FFALIGN(nb_samples * sample_size, align) :
133  FFALIGN(nb_samples * sample_size * nb_channels, align);
134  if (linesize)
135  *linesize = line_size;
136 
137  return planar ? line_size * nb_channels : line_size;
138 }
139 
140 int av_samples_fill_arrays(uint8_t **audio_data, int *linesize,
141  const uint8_t *buf, int nb_channels, int nb_samples,
142  enum AVSampleFormat sample_fmt, int align)
143 {
144  int ch, planar, buf_size, line_size;
145 
146  planar = av_sample_fmt_is_planar(sample_fmt);
147  buf_size = av_samples_get_buffer_size(&line_size, nb_channels, nb_samples,
148  sample_fmt, align);
149  if (buf_size < 0)
150  return buf_size;
151 
152  audio_data[0] = buf;
153  for (ch = 1; planar && ch < nb_channels; ch++)
154  audio_data[ch] = audio_data[ch-1] + line_size;
155 
156  if (linesize)
157  *linesize = line_size;
158 
159  return 0;
160 }
161 
162 int av_samples_alloc(uint8_t **audio_data, int *linesize, int nb_channels,
163  int nb_samples, enum AVSampleFormat sample_fmt, int align)
164 {
165  uint8_t *buf;
166  int size = av_samples_get_buffer_size(NULL, nb_channels, nb_samples,
167  sample_fmt, align);
168  if (size < 0)
169  return size;
170 
171  buf = av_malloc(size);
172  if (!buf)
173  return AVERROR(ENOMEM);
174 
175  size = av_samples_fill_arrays(audio_data, linesize, buf, nb_channels,
176  nb_samples, sample_fmt, align);
177  if (size < 0) {
178  av_free(buf);
179  return size;
180  }
181 
182  av_samples_set_silence(audio_data, 0, nb_samples, nb_channels, sample_fmt);
183 
184  return 0;
185 }
186 
187 int av_samples_copy(uint8_t **dst, uint8_t * const *src, int dst_offset,
188  int src_offset, int nb_samples, int nb_channels,
190 {
191  int planar = av_sample_fmt_is_planar(sample_fmt);
192  int planes = planar ? nb_channels : 1;
193  int block_align = av_get_bytes_per_sample(sample_fmt) * (planar ? 1 : nb_channels);
194  int data_size = nb_samples * block_align;
195  int i;
196 
197  dst_offset *= block_align;
198  src_offset *= block_align;
199 
200  for (i = 0; i < planes; i++)
201  memcpy(dst[i] + dst_offset, src[i] + src_offset, data_size);
202 
203  return 0;
204 }
205 
206 int av_samples_set_silence(uint8_t **audio_data, int offset, int nb_samples,
208 {
209  int planar = av_sample_fmt_is_planar(sample_fmt);
210  int planes = planar ? nb_channels : 1;
211  int block_align = av_get_bytes_per_sample(sample_fmt) * (planar ? 1 : nb_channels);
212  int data_size = nb_samples * block_align;
213  int fill_char = (sample_fmt == AV_SAMPLE_FMT_U8 ||
214  sample_fmt == AV_SAMPLE_FMT_U8P) ? 0x80 : 0x00;
215  int i;
216 
217  offset *= block_align;
218 
219  for (i = 0; i < planes; i++)
220  memset(audio_data[i] + offset, fill_char, data_size);
221 
222  return 0;
223 }
const char * name
Definition: samplefmt.c:27
Number of sample formats. DO NOT USE if linking dynamically.
Definition: samplefmt.h:63
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:61
int 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:108
struct SampleFmtInfo SampleFmtInfo
enum AVSampleFormat altform
planar<->packed alternative form
Definition: samplefmt.c:30
signed 16 bits
Definition: samplefmt.h:52
static const SampleFmtInfo sample_fmt_info[AV_SAMPLE_FMT_NB]
this table gives more information about formats
Definition: samplefmt.c:34
int av_samples_fill_arrays(uint8_t **audio_data, int *linesize, const uint8_t *buf, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)
Fill channel data pointers and linesize for samples with sample format sample_fmt.
Definition: samplefmt.c:140
uint8_t
AV_SAMPLE_FMT_U8
const char * name
enum AVSampleFormat av_get_planar_sample_fmt(enum AVSampleFormat sample_fmt)
Get the planar alternative form of the given sample format.
Definition: samplefmt.c:73
signed 32 bits, planar
Definition: samplefmt.h:59
float, planar
Definition: samplefmt.h:60
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:139
signed 32 bits
Definition: samplefmt.h:53
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:206
enum AVSampleFormat av_get_packed_sample_fmt(enum AVSampleFormat sample_fmt)
Get the packed alternative form of the given sample format.
Definition: samplefmt.c:64
const char * av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
Definition: samplefmt.c:47
int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
Return number of bytes per sample.
Definition: samplefmt.c:95
NULL
Definition: eval.c:52
sample_fmt
Definition: avconv_filter.c:63
int av_samples_alloc(uint8_t **audio_data, int *linesize, int nb_channels, int nb_samples, enum AVSampleFormat sample_fmt, int align)
Allocate a samples buffer for nb_samples samples, and fill data pointers and linesize accordingly...
Definition: samplefmt.c:162
AV_SAMPLE_FMT_NONE
Definition: avconv_filter.c:63
char * av_get_sample_fmt_string(char *buf, int buf_size, enum AVSampleFormat sample_fmt)
Generate a string corresponding to the sample format with sample_fmt, or a header if sample_fmt is ne...
Definition: samplefmt.c:82
int av_samples_copy(uint8_t **dst, uint8_t *const *src, int dst_offset, int src_offset, int nb_samples, int nb_channels, enum AVSampleFormat sample_fmt)
Copy samples from src to dst.
Definition: samplefmt.c:187
out nb_samples
int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt)
Check if the sample format is planar.
Definition: samplefmt.c:101
common internal and external API header
AVSampleFormat
Audio Sample Formats.
Definition: samplefmt.h:49
unsigned 8 bits, planar
Definition: samplefmt.h:57
signed 16 bits, planar
Definition: samplefmt.h:58
int nb_channels
double, planar
Definition: samplefmt.h:61
enum AVSampleFormat av_get_sample_fmt(const char *name)
Return a sample format corresponding to name, or AV_SAMPLE_FMT_NONE on error.
Definition: samplefmt.c:54