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source: vbox/trunk/src/libs/ffmpeg-20060710/libavcodec/dtsdec.c@ 10516

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1/*
2 * dtsdec.c : free DTS Coherent Acoustics stream decoder.
3 * Copyright (C) 2004 Benjamin Zores <[email protected]>
4 *
5 * This file is part of libavcodec.
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This library 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
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21
22#ifdef HAVE_AV_CONFIG_H
23#undef HAVE_AV_CONFIG_H
24#endif
25
26#include "avcodec.h"
27#include <dts.h>
28
29#include <stdlib.h>
30#include <string.h>
31
32#ifdef HAVE_MALLOC_H
33#include <malloc.h>
34#endif
35
36#define BUFFER_SIZE 18726
37#define HEADER_SIZE 14
38
39#ifdef LIBDTS_FIXED
40#define CONVERT_LEVEL (1 << 26)
41#define CONVERT_BIAS 0
42#else
43#define CONVERT_LEVEL 1
44#define CONVERT_BIAS 384
45#endif
46
47static inline
48int16_t convert (int32_t i)
49{
50#ifdef LIBDTS_FIXED
51 i >>= 15;
52#else
53 i -= 0x43c00000;
54#endif
55 return (i > 32767) ? 32767 : ((i < -32768) ? -32768 : i);
56}
57
58void
59convert2s16_2 (sample_t * _f, int16_t * s16)
60{
61 int i;
62 int32_t * f = (int32_t *) _f;
63
64 for (i = 0; i < 256; i++)
65 {
66 s16[2*i] = convert (f[i]);
67 s16[2*i+1] = convert (f[i+256]);
68 }
69}
70
71void
72convert2s16_4 (sample_t * _f, int16_t * s16)
73{
74 int i;
75 int32_t * f = (int32_t *) _f;
76
77 for (i = 0; i < 256; i++)
78 {
79 s16[4*i] = convert (f[i]);
80 s16[4*i+1] = convert (f[i+256]);
81 s16[4*i+2] = convert (f[i+512]);
82 s16[4*i+3] = convert (f[i+768]);
83 }
84}
85
86void
87convert2s16_5 (sample_t * _f, int16_t * s16)
88{
89 int i;
90 int32_t * f = (int32_t *) _f;
91
92 for (i = 0; i < 256; i++)
93 {
94 s16[5*i] = convert (f[i]);
95 s16[5*i+1] = convert (f[i+256]);
96 s16[5*i+2] = convert (f[i+512]);
97 s16[5*i+3] = convert (f[i+768]);
98 s16[5*i+4] = convert (f[i+1024]);
99 }
100}
101
102static void
103convert2s16_multi (sample_t * _f, int16_t * s16, int flags)
104{
105 int i;
106 int32_t * f = (int32_t *) _f;
107
108 switch (flags)
109 {
110 case DTS_MONO:
111 for (i = 0; i < 256; i++)
112 {
113 s16[5*i] = s16[5*i+1] = s16[5*i+2] = s16[5*i+3] = 0;
114 s16[5*i+4] = convert (f[i]);
115 }
116 break;
117 case DTS_CHANNEL:
118 case DTS_STEREO:
119 case DTS_DOLBY:
120 convert2s16_2 (_f, s16);
121 break;
122 case DTS_3F:
123 for (i = 0; i < 256; i++)
124 {
125 s16[5*i] = convert (f[i]);
126 s16[5*i+1] = convert (f[i+512]);
127 s16[5*i+2] = s16[5*i+3] = 0;
128 s16[5*i+4] = convert (f[i+256]);
129 }
130 break;
131 case DTS_2F2R:
132 convert2s16_4 (_f, s16);
133 break;
134 case DTS_3F2R:
135 convert2s16_5 (_f, s16);
136 break;
137 case DTS_MONO | DTS_LFE:
138 for (i = 0; i < 256; i++)
139 {
140 s16[6*i] = s16[6*i+1] = s16[6*i+2] = s16[6*i+3] = 0;
141 s16[6*i+4] = convert (f[i+256]);
142 s16[6*i+5] = convert (f[i]);
143 }
144 break;
145 case DTS_CHANNEL | DTS_LFE:
146 case DTS_STEREO | DTS_LFE:
147 case DTS_DOLBY | DTS_LFE:
148 for (i = 0; i < 256; i++)
149 {
150 s16[6*i] = convert (f[i+256]);
151 s16[6*i+1] = convert (f[i+512]);
152 s16[6*i+2] = s16[6*i+3] = s16[6*i+4] = 0;
153 s16[6*i+5] = convert (f[i]);
154 }
155 break;
156 case DTS_3F | DTS_LFE:
157 for (i = 0; i < 256; i++)
158 {
159 s16[6*i] = convert (f[i+256]);
160 s16[6*i+1] = convert (f[i+768]);
161 s16[6*i+2] = s16[6*i+3] = 0;
162 s16[6*i+4] = convert (f[i+512]);
163 s16[6*i+5] = convert (f[i]);
164 }
165 break;
166 case DTS_2F2R | DTS_LFE:
167 for (i = 0; i < 256; i++)
168 {
169 s16[6*i] = convert (f[i+256]);
170 s16[6*i+1] = convert (f[i+512]);
171 s16[6*i+2] = convert (f[i+768]);
172 s16[6*i+3] = convert (f[i+1024]);
173 s16[6*i+4] = 0;
174 s16[6*i+5] = convert (f[i]);
175 }
176 break;
177 case DTS_3F2R | DTS_LFE:
178 for (i = 0; i < 256; i++)
179 {
180 s16[6*i] = convert (f[i+256]);
181 s16[6*i+1] = convert (f[i+768]);
182 s16[6*i+2] = convert (f[i+1024]);
183 s16[6*i+3] = convert (f[i+1280]);
184 s16[6*i+4] = convert (f[i+512]);
185 s16[6*i+5] = convert (f[i]);
186 }
187 break;
188 }
189}
190
191static int
192channels_multi (int flags)
193{
194 if (flags & DTS_LFE)
195 return 6;
196 else if (flags & 1) /* center channel */
197 return 5;
198 else if ((flags & DTS_CHANNEL_MASK) == DTS_2F2R)
199 return 4;
200 else
201 return 2;
202}
203
204static int
205dts_decode_frame (AVCodecContext *avctx, void *data, int *data_size,
206 uint8_t *buff, int buff_size)
207{
208 uint8_t * start = buff;
209 uint8_t * end = buff + buff_size;
210 static uint8_t buf[BUFFER_SIZE];
211 static uint8_t * bufptr = buf;
212 static uint8_t * bufpos = buf + HEADER_SIZE;
213
214 static int sample_rate;
215 static int frame_length;
216 static int flags;
217 int bit_rate;
218 int len;
219 dts_state_t *state = avctx->priv_data;
220
221 *data_size = 0;
222
223 while (1)
224 {
225 len = end - start;
226 if (!len)
227 break;
228 if (len > bufpos - bufptr)
229 len = bufpos - bufptr;
230 memcpy (bufptr, start, len);
231 bufptr += len;
232 start += len;
233 if (bufptr != bufpos)
234 return start - buff;
235 if (bufpos != buf + HEADER_SIZE)
236 break;
237
238 {
239 int length;
240
241 length = dts_syncinfo (state, buf, &flags, &sample_rate,
242 &bit_rate, &frame_length);
243 if (!length)
244 {
245 av_log (NULL, AV_LOG_INFO, "skip\n");
246 for (bufptr = buf; bufptr < buf + HEADER_SIZE-1; bufptr++)
247 bufptr[0] = bufptr[1];
248 continue;
249 }
250 bufpos = buf + length;
251 }
252 }
253
254 {
255 level_t level;
256 sample_t bias;
257 int i;
258
259 flags = 2; /* ???????????? */
260 level = CONVERT_LEVEL;
261 bias = CONVERT_BIAS;
262
263 flags |= DTS_ADJUST_LEVEL;
264 if (dts_frame (state, buf, &flags, &level, bias))
265 goto error;
266 avctx->sample_rate = sample_rate;
267 avctx->channels = channels_multi (flags);
268 avctx->bit_rate = bit_rate;
269 for (i = 0; i < dts_blocks_num (state); i++)
270 {
271 if (dts_block (state))
272 goto error;
273 {
274 int chans;
275 chans = channels_multi (flags);
276 convert2s16_multi (dts_samples (state), data,
277 flags & (DTS_CHANNEL_MASK | DTS_LFE));
278
279 data += 256 * sizeof (int16_t) * chans;
280 *data_size += 256 * sizeof (int16_t) * chans;
281 }
282 }
283 bufptr = buf;
284 bufpos = buf + HEADER_SIZE;
285 return start-buff;
286 error:
287 av_log (NULL, AV_LOG_ERROR, "error\n");
288 bufptr = buf;
289 bufpos = buf + HEADER_SIZE;
290 }
291
292 return start-buff;
293}
294
295static int
296dts_decode_init (AVCodecContext *avctx)
297{
298 avctx->priv_data = dts_init (0);
299 if (avctx->priv_data == NULL)
300 return -1;
301
302 return 0;
303}
304
305static int
306dts_decode_end (AVCodecContext *s)
307{
308 return 0;
309}
310
311AVCodec dts_decoder = {
312 "dts",
313 CODEC_TYPE_AUDIO,
314 CODEC_ID_DTS,
315 sizeof (dts_state_t *),
316 dts_decode_init,
317 NULL,
318 dts_decode_end,
319 dts_decode_frame,
320};
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