Libav
dca.c
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1 /*
2  * DCA compatible decoder data
3  *
4  * This file is part of Libav.
5  *
6  * Libav is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * Libav is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <stdint.h>
22 #include <string.h>
23 
24 #include "put_bits.h"
25 #include "dca.h"
26 
27 const uint32_t avpriv_dca_sample_rates[16] =
28 {
29  0, 8000, 16000, 32000, 0, 0, 11025, 22050, 44100, 0, 0,
30  12000, 24000, 48000, 96000, 192000
31 };
32 
33 int ff_dca_convert_bitstream(const uint8_t *src, int src_size, uint8_t *dst,
34  int max_size)
35 {
36  uint32_t mrk;
37  int i, tmp;
38  const uint16_t *ssrc = (const uint16_t *) src;
39  uint16_t *sdst = (uint16_t *) dst;
40  PutBitContext pb;
41 
42  if ((unsigned) src_size > (unsigned) max_size)
43  src_size = max_size;
44 
45  mrk = AV_RB32(src);
46  switch (mrk) {
47  case DCA_MARKER_RAW_BE:
48  memcpy(dst, src, src_size);
49  return src_size;
50  case DCA_MARKER_RAW_LE:
51  for (i = 0; i < (src_size + 1) >> 1; i++)
52  *sdst++ = av_bswap16(*ssrc++);
53  return src_size;
54  case DCA_MARKER_14B_BE:
55  case DCA_MARKER_14B_LE:
56  init_put_bits(&pb, dst, max_size);
57  for (i = 0; i < (src_size + 1) >> 1; i++, src += 2) {
58  tmp = ((mrk == DCA_MARKER_14B_BE) ? AV_RB16(src) : AV_RL16(src)) & 0x3FFF;
59  put_bits(&pb, 14, tmp);
60  }
61  flush_put_bits(&pb);
62  return (put_bits_count(&pb) + 7) >> 3;
63  default:
64  return AVERROR_INVALIDDATA;
65  }
66 }
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
#define av_bswap16
Definition: bswap.h:31
int ff_dca_convert_bitstream(const uint8_t *src, int src_size, uint8_t *dst, int max_size)
Convert bitstream to one representation based on sync marker.
Definition: dca.c:33
#define AV_RL16
Definition: intreadwrite.h:42
uint8_t
#define AV_RB32
Definition: intreadwrite.h:130
#define AV_RB16
Definition: intreadwrite.h:53
static void put_bits(PutBitContext *s, int n, unsigned int value)
Write up to 31 bits into a bitstream.
Definition: put_bits.h:139
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:72
#define DCA_MARKER_14B_LE
Definition: dca.h:35
const uint32_t avpriv_dca_sample_rates[16]
Definition: dca.c:27
#define DCA_MARKER_RAW_LE
Definition: dca.h:33
#define DCA_MARKER_14B_BE
Definition: dca.h:34
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:88
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:53
#define DCA_MARKER_RAW_BE
DCA syncwords, also used for bitstream type detection.
Definition: dca.h:32
bitstream writer API