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dvaudiodec.c
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1 /*
2  * Copyright (c) 2012 Laurent Aimar
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/intreadwrite.h"
22 #include "avcodec.h"
23 #include "internal.h"
24 #include "dvaudio.h"
25 
26 typedef struct DVAudioContext {
28  int is_12bit;
29  int is_pal;
30  int16_t shuffle[2000];
32 
34 {
35  DVAudioContext *s = avctx->priv_data;
36  int i;
37 
38  if (avctx->channels != 2) {
39  av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
40  return AVERROR(EINVAL);
41  }
42 
43  if (avctx->codec_tag == 0x0215) {
44  s->block_size = 7200;
45  } else if (avctx->codec_tag == 0x0216) {
46  s->block_size = 8640;
47  } else if (avctx->block_align == 7200 ||
48  avctx->block_align == 8640) {
49  s->block_size = avctx->block_align;
50  } else {
51  return AVERROR(EINVAL);
52  }
53 
54  s->is_pal = s->block_size == 8640;
55  s->is_12bit = avctx->bits_per_coded_sample == 12;
58 
59  for (i = 0; i < FF_ARRAY_ELEMS(s->shuffle); i++) {
60  const unsigned a = s->is_pal ? 18 : 15;
61  const unsigned b = 3 * a;
62 
63  s->shuffle[i] = 80 * ((21 * (i % 3) + 9 * (i / 3) + ((i / a) % 3)) % b) +
64  (2 + s->is_12bit) * (i / b) + 8;
65  }
66 
67  return 0;
68 }
69 
70 static inline uint16_t dv_audio_12to16(uint16_t sample)
71 {
72  uint16_t shift, result;
73 
74  sample = (sample < 0x800) ? sample : sample | 0xf000;
75  shift = (sample & 0xf00) >> 8;
76 
77  if (shift < 0x2 || shift > 0xd) {
78  result = sample;
79  } else if (shift < 0x8) {
80  shift--;
81  result = (sample - (256 * shift)) << shift;
82  } else {
83  shift = 0xe - shift;
84  result = ((sample + ((256 * shift) + 1)) << shift) - 1;
85  }
86 
87  return result;
88 }
89 
90 static int decode_frame(AVCodecContext *avctx, void *data,
91  int *got_frame_ptr, AVPacket *pkt)
92 {
93  DVAudioContext *s = avctx->priv_data;
94  AVFrame *frame = data;
95  const uint8_t *src = pkt->data;
96  int16_t *dst;
97  int ret, i;
98 
99  if (pkt->size < s->block_size)
100  return AVERROR_INVALIDDATA;
101 
102  frame->nb_samples = dv_get_audio_sample_count(pkt->data + 244, s->is_pal);
103  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
104  return ret;
105  dst = (int16_t *)frame->data[0];
106 
107  for (i = 0; i < frame->nb_samples; i++) {
108  const uint8_t *v = &src[s->shuffle[i]];
109 
110  if (s->is_12bit) {
111  *dst++ = dv_audio_12to16((v[0] << 4) | ((v[2] >> 4) & 0x0f));
112  *dst++ = dv_audio_12to16((v[1] << 4) | ((v[2] >> 0) & 0x0f));
113  } else {
114  *dst++ = AV_RB16(&v[0]);
115  *dst++ = AV_RB16(&v[s->is_pal ? 4320 : 3600]);
116  }
117  }
118 
119  *got_frame_ptr = 1;
120 
121  return s->block_size;
122 }
123 
125  .name = "dvaudio",
126  .long_name = NULL_IF_CONFIG_SMALL("Ulead DV Audio"),
127  .type = AVMEDIA_TYPE_AUDIO,
128  .id = AV_CODEC_ID_DVAUDIO,
129  .init = decode_init,
130  .decode = decode_frame,
131  .capabilities = AV_CODEC_CAP_DR1,
132  .priv_data_size = sizeof(DVAudioContext),
133 };
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
static int shift(int a, int b)
Definition: sonic.c:82
This structure describes decoded (raw) audio or video data.
Definition: frame.h:201
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
int size
Definition: avcodec.h:1401
const char * b
Definition: vf_curves.c:113
static AVPacket pkt
#define AV_CH_LAYOUT_STEREO
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:87
#define src
Definition: vp8dsp.c:254
#define sample
AVCodec.
Definition: avcodec.h:3351
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:2180
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2151
uint8_t
#define av_cold
Definition: attributes.h:82
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1400
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2704
#define av_log(a,...)
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3358
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2194
static av_cold int decode_init(AVCodecContext *avctx)
Definition: dvaudiodec.c:33
static uint16_t dv_audio_12to16(uint16_t sample)
Definition: dvaudiodec.c:70
#define FF_ARRAY_ELEMS(a)
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1488
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1513
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1886
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *pkt)
Definition: dvaudiodec.c:90
static int dv_get_audio_sample_count(const uint8_t *buffer, int dsf)
Definition: dvaudio.h:24
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:215
common internal api header.
signed 16 bits
Definition: samplefmt.h:61
void * priv_data
Definition: avcodec.h:1515
int channels
number of audio channels
Definition: avcodec.h:2144
int16_t shuffle[2000]
Definition: dvaudiodec.c:30
AVCodec ff_dvaudio_decoder
Definition: dvaudiodec.c:124
This structure stores compressed data.
Definition: avcodec.h:1377
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:267
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:956
for(j=16;j >0;--j)