69c7002ad73c31be144393087a337168cc755f77
[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 "libavutil/intreadwrite.h"
41 #include "avcodec.h"
42
43 typedef struct DPCMContext {
44 int channels;
45 short roq_square_array[256];
46 long sample[2];//for SOL_DPCM
47 const int *sol_table;//for SOL_DPCM
48 } DPCMContext;
49
50 #define SE_16BIT(x) if (x & 0x8000) x -= 0x10000;
51
52 static const int interplay_delta_table[] = {
53 0, 1, 2, 3, 4, 5, 6, 7,
54 8, 9, 10, 11, 12, 13, 14, 15,
55 16, 17, 18, 19, 20, 21, 22, 23,
56 24, 25, 26, 27, 28, 29, 30, 31,
57 32, 33, 34, 35, 36, 37, 38, 39,
58 40, 41, 42, 43, 47, 51, 56, 61,
59 66, 72, 79, 86, 94, 102, 112, 122,
60 133, 145, 158, 173, 189, 206, 225, 245,
61 267, 292, 318, 348, 379, 414, 452, 493,
62 538, 587, 640, 699, 763, 832, 908, 991,
63 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993,
64 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008,
65 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059,
66 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206,
67 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589,
68 -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1,
69 1, 1, 5481, 10503, 15105, 19322, 23186, 26728,
70 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298,
71 -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597,
72 -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772,
73 -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373,
74 -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180,
75 -1081, -991, -908, -832, -763, -699, -640, -587,
76 -538, -493, -452, -414, -379, -348, -318, -292,
77 -267, -245, -225, -206, -189, -173, -158, -145,
78 -133, -122, -112, -102, -94, -86, -79, -72,
79 -66, -61, -56, -51, -47, -43, -42, -41,
80 -40, -39, -38, -37, -36, -35, -34, -33,
81 -32, -31, -30, -29, -28, -27, -26, -25,
82 -24, -23, -22, -21, -20, -19, -18, -17,
83 -16, -15, -14, -13, -12, -11, -10, -9,
84 -8, -7, -6, -5, -4, -3, -2, -1
85
86 };
87
88 static const int sol_table_old[16] =
89 { 0x0, 0x1, 0x2 , 0x3, 0x6, 0xA, 0xF, 0x15,
90 -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0};
91
92 static const int sol_table_new[16] =
93 { 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
94 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15};
95
96 static const int sol_table_16[128] = {
97 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
98 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
99 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
100 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
101 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
102 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
103 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
104 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
105 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
106 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
107 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
108 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
109 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
110 };
111
112
113
114 static av_cold int dpcm_decode_init(AVCodecContext *avctx)
115 {
116 DPCMContext *s = avctx->priv_data;
117 int i;
118 short square;
119
120 s->channels = avctx->channels;
121 s->sample[0] = s->sample[1] = 0;
122
123 switch(avctx->codec->id) {
124
125 case CODEC_ID_ROQ_DPCM:
126 /* initialize square table */
127 for (i = 0; i < 128; i++) {
128 square = i * i;
129 s->roq_square_array[i] = square;
130 s->roq_square_array[i + 128] = -square;
131 }
132 break;
133
134
135 case CODEC_ID_SOL_DPCM:
136 switch(avctx->codec_tag){
137 case 1:
138 s->sol_table=sol_table_old;
139 s->sample[0] = s->sample[1] = 0x80;
140 break;
141 case 2:
142 s->sol_table=sol_table_new;
143 s->sample[0] = s->sample[1] = 0x80;
144 break;
145 case 3:
146 s->sol_table=sol_table_16;
147 break;
148 default:
149 av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
150 return -1;
151 }
152 break;
153
154 default:
155 break;
156 }
157
158 avctx->sample_fmt = SAMPLE_FMT_S16;
159 return 0;
160 }
161
162 static int dpcm_decode_frame(AVCodecContext *avctx,
163 void *data, int *data_size,
164 AVPacket *avpkt)
165 {
166 const uint8_t *buf = avpkt->data;
167 int buf_size = avpkt->size;
168 DPCMContext *s = avctx->priv_data;
169 int in, out = 0;
170 int predictor[2];
171 int channel_number = 0;
172 short *output_samples = data;
173 int shift[2];
174 unsigned char byte;
175 short diff;
176
177 if (!buf_size)
178 return 0;
179
180 // almost every DPCM variant expands one byte of data into two
181 if(*data_size/2 < buf_size)
182 return -1;
183
184 switch(avctx->codec->id) {
185
186 case CODEC_ID_ROQ_DPCM:
187 if (s->channels == 1)
188 predictor[0] = AV_RL16(&buf[6]);
189 else {
190 predictor[0] = buf[7] << 8;
191 predictor[1] = buf[6] << 8;
192 }
193 SE_16BIT(predictor[0]);
194 SE_16BIT(predictor[1]);
195
196 /* decode the samples */
197 for (in = 8, out = 0; in < buf_size; in++, out++) {
198 predictor[channel_number] += s->roq_square_array[buf[in]];
199 predictor[channel_number] = av_clip_int16(predictor[channel_number]);
200 output_samples[out] = predictor[channel_number];
201
202 /* toggle channel */
203 channel_number ^= s->channels - 1;
204 }
205 break;
206
207 case CODEC_ID_INTERPLAY_DPCM:
208 in = 6; /* skip over the stream mask and stream length */
209 predictor[0] = AV_RL16(&buf[in]);
210 in += 2;
211 SE_16BIT(predictor[0])
212 output_samples[out++] = predictor[0];
213 if (s->channels == 2) {
214 predictor[1] = AV_RL16(&buf[in]);
215 in += 2;
216 SE_16BIT(predictor[1])
217 output_samples[out++] = predictor[1];
218 }
219
220 while (in < buf_size) {
221 predictor[channel_number] += interplay_delta_table[buf[in++]];
222 predictor[channel_number] = av_clip_int16(predictor[channel_number]);
223 output_samples[out++] = predictor[channel_number];
224
225 /* toggle channel */
226 channel_number ^= s->channels - 1;
227 }
228
229 break;
230
231 case CODEC_ID_XAN_DPCM:
232 in = 0;
233 shift[0] = shift[1] = 4;
234 predictor[0] = AV_RL16(&buf[in]);
235 in += 2;
236 SE_16BIT(predictor[0]);
237 if (s->channels == 2) {
238 predictor[1] = AV_RL16(&buf[in]);
239 in += 2;
240 SE_16BIT(predictor[1]);
241 }
242
243 while (in < buf_size) {
244 byte = buf[in++];
245 diff = (byte & 0xFC) << 8;
246 if ((byte & 0x03) == 3)
247 shift[channel_number]++;
248 else
249 shift[channel_number] -= (2 * (byte & 3));
250 /* saturate the shifter to a lower limit of 0 */
251 if (shift[channel_number] < 0)
252 shift[channel_number] = 0;
253
254 diff >>= shift[channel_number];
255 predictor[channel_number] += diff;
256
257 predictor[channel_number] = av_clip_int16(predictor[channel_number]);
258 output_samples[out++] = predictor[channel_number];
259
260 /* toggle channel */
261 channel_number ^= s->channels - 1;
262 }
263 break;
264 case CODEC_ID_SOL_DPCM:
265 in = 0;
266 if (avctx->codec_tag != 3) {
267 if(*data_size/4 < buf_size)
268 return -1;
269 while (in < buf_size) {
270 int n1, n2;
271 n1 = (buf[in] >> 4) & 0xF;
272 n2 = buf[in++] & 0xF;
273 s->sample[0] += s->sol_table[n1];
274 if (s->sample[0] < 0) s->sample[0] = 0;
275 if (s->sample[0] > 255) s->sample[0] = 255;
276 output_samples[out++] = (s->sample[0] - 128) << 8;
277 s->sample[s->channels - 1] += s->sol_table[n2];
278 if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0;
279 if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255;
280 output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8;
281 }
282 } else {
283 while (in < buf_size) {
284 int n;
285 n = buf[in++];
286 if (n & 0x80) s->sample[channel_number] -= s->sol_table[n & 0x7F];
287 else s->sample[channel_number] += s->sol_table[n & 0x7F];
288 s->sample[channel_number] = av_clip_int16(s->sample[channel_number]);
289 output_samples[out++] = s->sample[channel_number];
290 /* toggle channel */
291 channel_number ^= s->channels - 1;
292 }
293 }
294 break;
295 }
296
297 *data_size = out * sizeof(short);
298 return buf_size;
299 }
300
301 #define DPCM_DECODER(id, name, long_name_) \
302 AVCodec name ## _decoder = { \
303 #name, \
304 CODEC_TYPE_AUDIO, \
305 id, \
306 sizeof(DPCMContext), \
307 dpcm_decode_init, \
308 NULL, \
309 NULL, \
310 dpcm_decode_frame, \
311 .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
312 };
313
314 DPCM_DECODER(CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
315 DPCM_DECODER(CODEC_ID_ROQ_DPCM, roq_dpcm, "DPCM id RoQ");
316 DPCM_DECODER(CODEC_ID_SOL_DPCM, sol_dpcm, "DPCM Sol");
317 DPCM_DECODER(CODEC_ID_XAN_DPCM, xan_dpcm, "DPCM Xan");