ff684aeb432eab656e4242e1df08fc408542abf1
[libav.git] / libavcodec / dpcm.c
1 /*
2 * Assorted DPCM codecs
3 * Copyright (c) 2003 The ffmpeg Project.
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (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 GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License 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 /**
23 * @file: dpcm.c
24 * Assorted DPCM (differential pulse code modulation) audio codecs
25 * by Mike Melanson (melanson@pcisys.net)
26 * Xan DPCM decoder by Mario Brito (mbrito@student.dei.uc.pt)
27 * for more information on the specific data formats, visit:
28 * http://www.pcisys.net/~melanson/codecs/simpleaudio.html
29 * SOL DPCMs implemented by Konstantin Shishkov
30 *
31 * Note about using the Xan DPCM decoder: Xan DPCM is used in AVI files
32 * found in the Wing Commander IV computer game. These AVI files contain
33 * WAVEFORMAT headers which report the audio format as 0x01: raw PCM.
34 * Clearly incorrect. To detect Xan DPCM, you will probably have to
35 * special-case your AVI demuxer to use Xan DPCM if the file uses 'Xxan'
36 * (Xan video) for its video codec. Alternately, such AVI files also contain
37 * the fourcc 'Axan' in the 'auds' chunk of the AVI header.
38 */
39
40 #include "avcodec.h"
41
42 typedef struct DPCMContext {
43 int channels;
44 short roq_square_array[256];
45 long sample[2];//for SOL_DPCM
46 const int *sol_table;//for SOL_DPCM
47 } DPCMContext;
48
49 #define SE_16BIT(x) if (x & 0x8000) x -= 0x10000;
50
51 static const int interplay_delta_table[] = {
52 0, 1, 2, 3, 4, 5, 6, 7,
53 8, 9, 10, 11, 12, 13, 14, 15,
54 16, 17, 18, 19, 20, 21, 22, 23,
55 24, 25, 26, 27, 28, 29, 30, 31,
56 32, 33, 34, 35, 36, 37, 38, 39,
57 40, 41, 42, 43, 47, 51, 56, 61,
58 66, 72, 79, 86, 94, 102, 112, 122,
59 133, 145, 158, 173, 189, 206, 225, 245,
60 267, 292, 318, 348, 379, 414, 452, 493,
61 538, 587, 640, 699, 763, 832, 908, 991,
62 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993,
63 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008,
64 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059,
65 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206,
66 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589,
67 -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1,
68 1, 1, 5481, 10503, 15105, 19322, 23186, 26728,
69 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298,
70 -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597,
71 -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772,
72 -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373,
73 -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180,
74 -1081, -991, -908, -832, -763, -699, -640, -587,
75 -538, -493, -452, -414, -379, -348, -318, -292,
76 -267, -245, -225, -206, -189, -173, -158, -145,
77 -133, -122, -112, -102, -94, -86, -79, -72,
78 -66, -61, -56, -51, -47, -43, -42, -41,
79 -40, -39, -38, -37, -36, -35, -34, -33,
80 -32, -31, -30, -29, -28, -27, -26, -25,
81 -24, -23, -22, -21, -20, -19, -18, -17,
82 -16, -15, -14, -13, -12, -11, -10, -9,
83 -8, -7, -6, -5, -4, -3, -2, -1
84
85 };
86
87 static const int sol_table_old[16] =
88 { 0x0, 0x1, 0x2 , 0x3, 0x6, 0xA, 0xF, 0x15,
89 -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0};
90
91 static const int sol_table_new[16] =
92 { 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
93 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15};
94
95 static const int sol_table_16[128] = {
96 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
97 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
98 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
99 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
100 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
101 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
102 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
103 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
104 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
105 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
106 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
107 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
108 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
109 };
110
111
112
113 static av_cold int dpcm_decode_init(AVCodecContext *avctx)
114 {
115 DPCMContext *s = avctx->priv_data;
116 int i;
117 short square;
118
119 s->channels = avctx->channels;
120 s->sample[0] = s->sample[1] = 0;
121
122 switch(avctx->codec->id) {
123
124 case CODEC_ID_ROQ_DPCM:
125 /* initialize square table */
126 for (i = 0; i < 128; i++) {
127 square = i * i;
128 s->roq_square_array[i] = square;
129 s->roq_square_array[i + 128] = -square;
130 }
131 break;
132
133
134 case CODEC_ID_SOL_DPCM:
135 switch(avctx->codec_tag){
136 case 1:
137 s->sol_table=sol_table_old;
138 s->sample[0] = s->sample[1] = 0x80;
139 break;
140 case 2:
141 s->sol_table=sol_table_new;
142 s->sample[0] = s->sample[1] = 0x80;
143 break;
144 case 3:
145 s->sol_table=sol_table_16;
146 break;
147 default:
148 av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
149 return -1;
150 }
151 break;
152
153 default:
154 break;
155 }
156
157 avctx->sample_fmt = SAMPLE_FMT_S16;
158 return 0;
159 }
160
161 static int dpcm_decode_frame(AVCodecContext *avctx,
162 void *data, int *data_size,
163 const uint8_t *buf, int buf_size)
164 {
165 DPCMContext *s = avctx->priv_data;
166 int in, out = 0;
167 int predictor[2];
168 int channel_number = 0;
169 short *output_samples = data;
170 int shift[2];
171 unsigned char byte;
172 short diff;
173
174 if (!buf_size)
175 return 0;
176
177 // almost every DPCM variant expands one byte of data into two
178 if(*data_size/2 < buf_size)
179 return -1;
180
181 switch(avctx->codec->id) {
182
183 case CODEC_ID_ROQ_DPCM:
184 if (s->channels == 1)
185 predictor[0] = AV_RL16(&buf[6]);
186 else {
187 predictor[0] = buf[7] << 8;
188 predictor[1] = buf[6] << 8;
189 }
190 SE_16BIT(predictor[0]);
191 SE_16BIT(predictor[1]);
192
193 /* decode the samples */
194 for (in = 8, out = 0; in < buf_size; in++, out++) {
195 predictor[channel_number] += s->roq_square_array[buf[in]];
196 predictor[channel_number] = av_clip_int16(predictor[channel_number]);
197 output_samples[out] = predictor[channel_number];
198
199 /* toggle channel */
200 channel_number ^= s->channels - 1;
201 }
202 break;
203
204 case CODEC_ID_INTERPLAY_DPCM:
205 in = 6; /* skip over the stream mask and stream length */
206 predictor[0] = AV_RL16(&buf[in]);
207 in += 2;
208 SE_16BIT(predictor[0])
209 output_samples[out++] = predictor[0];
210 if (s->channels == 2) {
211 predictor[1] = AV_RL16(&buf[in]);
212 in += 2;
213 SE_16BIT(predictor[1])
214 output_samples[out++] = predictor[1];
215 }
216
217 while (in < buf_size) {
218 predictor[channel_number] += interplay_delta_table[buf[in++]];
219 predictor[channel_number] = av_clip_int16(predictor[channel_number]);
220 output_samples[out++] = predictor[channel_number];
221
222 /* toggle channel */
223 channel_number ^= s->channels - 1;
224 }
225
226 break;
227
228 case CODEC_ID_XAN_DPCM:
229 in = 0;
230 shift[0] = shift[1] = 4;
231 predictor[0] = AV_RL16(&buf[in]);
232 in += 2;
233 SE_16BIT(predictor[0]);
234 if (s->channels == 2) {
235 predictor[1] = AV_RL16(&buf[in]);
236 in += 2;
237 SE_16BIT(predictor[1]);
238 }
239
240 while (in < buf_size) {
241 byte = buf[in++];
242 diff = (byte & 0xFC) << 8;
243 if ((byte & 0x03) == 3)
244 shift[channel_number]++;
245 else
246 shift[channel_number] -= (2 * (byte & 3));
247 /* saturate the shifter to a lower limit of 0 */
248 if (shift[channel_number] < 0)
249 shift[channel_number] = 0;
250
251 diff >>= shift[channel_number];
252 predictor[channel_number] += diff;
253
254 predictor[channel_number] = av_clip_int16(predictor[channel_number]);
255 output_samples[out++] = predictor[channel_number];
256
257 /* toggle channel */
258 channel_number ^= s->channels - 1;
259 }
260 break;
261 case CODEC_ID_SOL_DPCM:
262 in = 0;
263 if (avctx->codec_tag != 3) {
264 if(*data_size/4 < buf_size)
265 return -1;
266 while (in < buf_size) {
267 int n1, n2;
268 n1 = (buf[in] >> 4) & 0xF;
269 n2 = buf[in++] & 0xF;
270 s->sample[0] += s->sol_table[n1];
271 if (s->sample[0] < 0) s->sample[0] = 0;
272 if (s->sample[0] > 255) s->sample[0] = 255;
273 output_samples[out++] = (s->sample[0] - 128) << 8;
274 s->sample[s->channels - 1] += s->sol_table[n2];
275 if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0;
276 if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255;
277 output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8;
278 }
279 } else {
280 while (in < buf_size) {
281 int n;
282 n = buf[in++];
283 if (n & 0x80) s->sample[channel_number] -= s->sol_table[n & 0x7F];
284 else s->sample[channel_number] += s->sol_table[n & 0x7F];
285 s->sample[channel_number] = av_clip_int16(s->sample[channel_number]);
286 output_samples[out++] = s->sample[channel_number];
287 /* toggle channel */
288 channel_number ^= s->channels - 1;
289 }
290 }
291 break;
292 }
293
294 *data_size = out * sizeof(short);
295 return buf_size;
296 }
297
298 #define DPCM_DECODER(id, name, long_name_) \
299 AVCodec name ## _decoder = { \
300 #name, \
301 CODEC_TYPE_AUDIO, \
302 id, \
303 sizeof(DPCMContext), \
304 dpcm_decode_init, \
305 NULL, \
306 NULL, \
307 dpcm_decode_frame, \
308 .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
309 };
310
311 DPCM_DECODER(CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "Interplay DPCM");
312 DPCM_DECODER(CODEC_ID_ROQ_DPCM, roq_dpcm, "id RoQ DPCM");
313 DPCM_DECODER(CODEC_ID_SOL_DPCM, sol_dpcm, "Sol DPCM");
314 DPCM_DECODER(CODEC_ID_XAN_DPCM, xan_dpcm, "Xan DPCM");