fix multichannel decoding
[libav.git] / libavcodec / dtsdec.c
1 /*
2 * dtsdec.c : free DTS Coherent Acoustics stream decoder.
3 * Copyright (C) 2004 Benjamin Zores <ben@geexbox.org>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "avcodec.h"
23 #include <dts.h>
24
25 #include <stdlib.h>
26 #include <string.h>
27
28 #define BUFFER_SIZE 18726
29 #define HEADER_SIZE 14
30
31 #define CONVERT_LEVEL 1
32 #define CONVERT_BIAS 0
33
34 typedef struct DTSContext {
35 dts_state_t *state;
36 uint8_t buf[BUFFER_SIZE];
37 uint8_t *bufptr;
38 uint8_t *bufpos;
39 } DTSContext;
40
41 static inline int16_t
42 convert(sample_t s)
43 {
44 return s * 0x7fff;
45 }
46
47 static void
48 convert2s16_multi(sample_t *f, int16_t *s16, int flags)
49 {
50 int i;
51
52 switch(flags & (DTS_CHANNEL_MASK | DTS_LFE)){
53 case DTS_MONO:
54 for(i = 0; i < 256; i++){
55 s16[5*i] = s16[5*i+1] = s16[5*i+2] = s16[5*i+3] = 0;
56 s16[5*i+4] = convert(f[i]);
57 }
58 case DTS_CHANNEL:
59 case DTS_STEREO:
60 case DTS_DOLBY:
61 for(i = 0; i < 256; i++){
62 s16[2*i] = convert(f[i]);
63 s16[2*i+1] = convert(f[i+256]);
64 }
65 case DTS_3F:
66 for(i = 0; i < 256; i++){
67 s16[5*i] = convert(f[i+256]);
68 s16[5*i+1] = convert(f[i+512]);
69 s16[5*i+2] = s16[5*i+3] = 0;
70 s16[5*i+4] = convert(f[i]);
71 }
72 case DTS_2F2R:
73 for(i = 0; i < 256; i++){
74 s16[4*i] = convert(f[i]);
75 s16[4*i+1] = convert(f[i+256]);
76 s16[4*i+2] = convert(f[i+512]);
77 s16[4*i+3] = convert(f[i+768]);
78 }
79 case DTS_3F2R:
80 for(i = 0; i < 256; i++){
81 s16[5*i] = convert(f[i+256]);
82 s16[5*i+1] = convert(f[i+512]);
83 s16[5*i+2] = convert(f[i+768]);
84 s16[5*i+3] = convert(f[i+1024]);
85 s16[5*i+4] = convert(f[i]);
86 }
87 case DTS_MONO | DTS_LFE:
88 for(i = 0; i < 256; i++){
89 s16[6*i] = s16[6*i+1] = s16[6*i+2] = s16[6*i+3] = 0;
90 s16[6*i+4] = convert(f[i]);
91 s16[6*i+5] = convert(f[i+256]);
92 }
93 case DTS_CHANNEL | DTS_LFE:
94 case DTS_STEREO | DTS_LFE:
95 case DTS_DOLBY | DTS_LFE:
96 for(i = 0; i < 256; i++){
97 s16[6*i] = convert(f[i]);
98 s16[6*i+1] = convert(f[i+256]);
99 s16[6*i+2] = s16[6*i+3] = s16[6*i+4] = 0;
100 s16[6*i+5] = convert(f[i+512]);
101 }
102 case DTS_3F | DTS_LFE:
103 for(i = 0; i < 256; i++){
104 s16[6*i] = convert(f[i+256]);
105 s16[6*i+1] = convert(f[i+512]);
106 s16[6*i+2] = s16[6*i+3] = 0;
107 s16[6*i+4] = convert(f[i]);
108 s16[6*i+5] = convert(f[i+768]);
109 }
110 case DTS_2F2R | DTS_LFE:
111 for(i = 0; i < 256; i++){
112 s16[6*i] = convert(f[i]);
113 s16[6*i+1] = convert(f[i+256]);
114 s16[6*i+2] = convert(f[i+512]);
115 s16[6*i+3] = convert(f[i+768]);
116 s16[6*i+4] = 0;
117 s16[6*i+5] = convert(f[i+1024]);
118 }
119 case DTS_3F2R | DTS_LFE:
120 for(i = 0; i < 256; i++){
121 s16[6*i] = convert(f[i+256]);
122 s16[6*i+1] = convert(f[i+512]);
123 s16[6*i+2] = convert(f[i+768]);
124 s16[6*i+3] = convert(f[i+1024]);
125 s16[6*i+4] = convert(f[i]);
126 s16[6*i+5] = convert(f[i+1280]);
127 }
128 }
129 }
130
131 static int
132 channels_multi(int flags)
133 {
134 switch(flags & (DTS_CHANNEL_MASK | DTS_LFE)){
135 case DTS_CHANNEL:
136 case DTS_STEREO:
137 case DTS_DOLBY:
138 return 2;
139 case DTS_2F2R:
140 return 4;
141 case DTS_MONO:
142 case DTS_3F:
143 case DTS_3F2R:
144 return 5;
145 case DTS_MONO | DTS_LFE:
146 case DTS_CHANNEL | DTS_LFE:
147 case DTS_STEREO | DTS_LFE:
148 case DTS_DOLBY | DTS_LFE:
149 case DTS_3F | DTS_LFE:
150 case DTS_2F2R | DTS_LFE:
151 case DTS_3F2R | DTS_LFE:
152 return 6;
153 }
154
155 return -1;
156 }
157
158 static int
159 dts_decode_frame(AVCodecContext * avctx, void *data, int *data_size,
160 uint8_t * buff, int buff_size)
161 {
162 DTSContext *s = avctx->priv_data;
163 uint8_t *start = buff;
164 uint8_t *end = buff + buff_size;
165 int16_t *out_samples = data;
166 int sample_rate;
167 int frame_length;
168 int flags;
169 int bit_rate;
170 int len;
171 level_t level;
172 sample_t bias;
173 int nblocks;
174 int i;
175
176 *data_size = 0;
177
178 while(1) {
179 int length;
180
181 len = end - start;
182 if(!len)
183 break;
184 if(len > s->bufpos - s->bufptr)
185 len = s->bufpos - s->bufptr;
186 memcpy(s->bufptr, start, len);
187 s->bufptr += len;
188 start += len;
189 if(s->bufptr != s->bufpos)
190 return start - buff;
191 if(s->bufpos != s->buf + HEADER_SIZE)
192 break;
193
194 length = dts_syncinfo(s->state, s->buf, &flags, &sample_rate,
195 &bit_rate, &frame_length);
196 if(!length) {
197 av_log(NULL, AV_LOG_INFO, "skip\n");
198 for(s->bufptr = s->buf; s->bufptr < s->buf + HEADER_SIZE - 1; s->bufptr++)
199 s->bufptr[0] = s->bufptr[1];
200 continue;
201 }
202 s->bufpos = s->buf + length;
203 }
204
205 level = CONVERT_LEVEL;
206 bias = CONVERT_BIAS;
207
208 flags |= DTS_ADJUST_LEVEL;
209 if(dts_frame(s->state, s->buf, &flags, &level, bias)) {
210 av_log(avctx, AV_LOG_ERROR, "dts_frame() failed\n");
211 goto end;
212 }
213
214 avctx->sample_rate = sample_rate;
215 avctx->channels = channels_multi(flags);
216 avctx->bit_rate = bit_rate;
217
218 nblocks = dts_blocks_num(s->state);
219
220 for(i = 0; i < nblocks; i++) {
221 if(dts_block(s->state)) {
222 av_log(avctx, AV_LOG_ERROR, "dts_block() failed\n");
223 goto end;
224 }
225
226 convert2s16_multi(dts_samples(s->state), out_samples, flags);
227
228 out_samples += 256 * avctx->channels;
229 *data_size += 256 * sizeof(int16_t) * avctx->channels;
230 }
231
232 end:
233 s->bufptr = s->buf;
234 s->bufpos = s->buf + HEADER_SIZE;
235 return start - buff;
236 }
237
238 static int
239 dts_decode_init(AVCodecContext * avctx)
240 {
241 DTSContext *s = avctx->priv_data;
242 s->bufptr = s->buf;
243 s->bufpos = s->buf + HEADER_SIZE;
244 s->state = dts_init(0);
245 if(s->state == NULL)
246 return -1;
247
248 return 0;
249 }
250
251 static int
252 dts_decode_end(AVCodecContext * avctx)
253 {
254 DTSContext *s = avctx->priv_data;
255 dts_free(s->state);
256 return 0;
257 }
258
259 AVCodec dts_decoder = {
260 "dts",
261 CODEC_TYPE_AUDIO,
262 CODEC_ID_DTS,
263 sizeof(DTSContext),
264 dts_decode_init,
265 NULL,
266 dts_decode_end,
267 dts_decode_frame,
268 };