samplefmt.c
Go to the documentation of this file.
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  align = 1;
122  nb_samples = FFALIGN(nb_samples, 32);
123  }
124 
125  /* check for integer overflow */
126  if (nb_channels > INT_MAX / align ||
127  (int64_t)nb_channels * nb_samples > (INT_MAX - (align * nb_channels)) / sample_size)
128  return AVERROR(EINVAL);
129 
130  line_size = planar ? FFALIGN(nb_samples * sample_size, align) :
131  FFALIGN(nb_samples * sample_size * nb_channels, align);
132  if (linesize)
133  *linesize = line_size;
134 
135  return planar ? line_size * nb_channels : line_size;
136 }
137 
138 int av_samples_fill_arrays(uint8_t **audio_data, int *linesize,
139  const uint8_t *buf, int nb_channels, int nb_samples,
140  enum AVSampleFormat sample_fmt, int align)
141 {
142  int ch, planar, buf_size, line_size;
143 
144  planar = av_sample_fmt_is_planar(sample_fmt);
145  buf_size = av_samples_get_buffer_size(&line_size, nb_channels, nb_samples,
146  sample_fmt, align);
147  if (buf_size < 0)
148  return buf_size;
149 
150  audio_data[0] = buf;
151  for (ch = 1; planar && ch < nb_channels; ch++)
152  audio_data[ch] = audio_data[ch-1] + line_size;
153 
154  if (linesize)
155  *linesize = line_size;
156 
157  return 0;
158 }
159 
160 int av_samples_alloc(uint8_t **audio_data, int *linesize, int nb_channels,
161  int nb_samples, enum AVSampleFormat sample_fmt, int align)
162 {
163  uint8_t *buf;
164  int size = av_samples_get_buffer_size(NULL, nb_channels, nb_samples,
165  sample_fmt, align);
166  if (size < 0)
167  return size;
168 
169  buf = av_malloc(size);
170  if (!buf)
171  return AVERROR(ENOMEM);
172 
173  size = av_samples_fill_arrays(audio_data, linesize, buf, nb_channels,
174  nb_samples, sample_fmt, align);
175  if (size < 0) {
176  av_free(buf);
177  return size;
178  }
179 
180  av_samples_set_silence(audio_data, 0, nb_samples, nb_channels, sample_fmt);
181 
182  return 0;
183 }
184 
185 int av_samples_copy(uint8_t **dst, uint8_t * const *src, int dst_offset,
186  int src_offset, int nb_samples, int nb_channels,
188 {
189  int planar = av_sample_fmt_is_planar(sample_fmt);
190  int planes = planar ? nb_channels : 1;
191  int block_align = av_get_bytes_per_sample(sample_fmt) * (planar ? 1 : nb_channels);
192  int data_size = nb_samples * block_align;
193  int i;
194 
195  dst_offset *= block_align;
196  src_offset *= block_align;
197 
198  for (i = 0; i < planes; i++)
199  memcpy(dst[i] + dst_offset, src[i] + src_offset, data_size);
200 
201  return 0;
202 }
203 
204 int av_samples_set_silence(uint8_t **audio_data, int offset, int nb_samples,
206 {
207  int planar = av_sample_fmt_is_planar(sample_fmt);
208  int planes = planar ? nb_channels : 1;
209  int block_align = av_get_bytes_per_sample(sample_fmt) * (planar ? 1 : nb_channels);
210  int data_size = nb_samples * block_align;
211  int fill_char = (sample_fmt == AV_SAMPLE_FMT_U8 ||
212  sample_fmt == AV_SAMPLE_FMT_U8P) ? 0x80 : 0x00;
213  int i;
214 
215  offset *= block_align;
216 
217  for (i = 0; i < planes; i++)
218  memset(audio_data[i] + offset, fill_char, data_size);
219 
220  return 0;
221 }