quicktime/ffmpeg/libavcodec/dpcm.c

   1 /*
   2  * Assorted DPCM codecs
   3  * Copyright (c) 2003 The ffmpeg Project.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 /**
  21  * @file: dpcm.c
  22  * Assorted DPCM (differential pulse code modulation) audio codecs
  23  * by Mike Melanson (melanson@pcisys.net)
  24  * Xan DPCM decoder by Mario Brito (mbrito@student.dei.uc.pt)
  25  * for more information on the specific data formats, visit:
  26  *   http://www.pcisys.net/~melanson/codecs/simpleaudio.html
  27  * SOL DPCMs implemented by Konstantin Shishkov
  28  *
  29  * Note about using the Xan DPCM decoder: Xan DPCM is used in AVI files
  30  * found in the Wing Commander IV computer game. These AVI files contain
  31  * WAVEFORMAT headers which report the audio format as 0x01: raw PCM.
  32  * Clearly incorrect. To detect Xan DPCM, you will probably have to
  33  * special-case your AVI demuxer to use Xan DPCM if the file uses 'Xxan'
  34  * (Xan video) for its video codec. Alternately, such AVI files also contain
  35  * the fourcc 'Axan' in the 'auds' chunk of the AVI header.
  36  */
  37
  38 #include "avcodec.h"
  39
  40 typedef struct DPCMContext {
  41     int channels;
  42     short roq_square_array[256];
  43     long sample[2];//for SOL_DPCM
  44     int *sol_table;//for SOL_DPCM
  45 } DPCMContext;
  46
  47 #define SATURATE_S16(x)  if (x < -32768) x = -32768; \
  48   else if (x > 32767) x = 32767;
  49 #define SE_16BIT(x)  if (x & 0x8000) x -= 0x10000;
  50
  51 static 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 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 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 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 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     return 0;
 158 }
 159
 160 static int dpcm_decode_frame(AVCodecContext *avctx,
 161                              void *data, int *data_size,
 162                              uint8_t *buf, int buf_size)
 163 {
 164     DPCMContext *s = avctx->priv_data;
 165     int in, out = 0;
 166     int predictor[2];
 167     int channel_number = 0;
 168     short *output_samples = data;
 169     int shift[2];
 170     unsigned char byte;
 171     short diff;
 172
 173     if (!buf_size)
 174         return 0;
 175
 176     switch(avctx->codec->id) {
 177
 178     case CODEC_ID_ROQ_DPCM:
 179         if (s->channels == 1)
 180             predictor[0] = LE_16(&buf[6]);
 181         else {
 182             predictor[0] = buf[7] << 8;
 183             predictor[1] = buf[6] << 8;
 184         }
 185         SE_16BIT(predictor[0]);
 186         SE_16BIT(predictor[1]);
 187
 188         /* decode the samples */
 189         for (in = 8, out = 0; in < buf_size; in++, out++) {
 190             predictor[channel_number] += s->roq_square_array[buf[in]];
 191             SATURATE_S16(predictor[channel_number]);
 192             output_samples[out] = predictor[channel_number];
 193
 194             /* toggle channel */
 195             channel_number ^= s->channels - 1;
 196         }
 197         break;
 198
 199     case CODEC_ID_INTERPLAY_DPCM:
 200         in = 6;  /* skip over the stream mask and stream length */
 201         predictor[0] = LE_16(&buf[in]);
 202         in += 2;
 203         SE_16BIT(predictor[0])
 204         output_samples[out++] = predictor[0];
 205         if (s->channels == 2) {
 206             predictor[1] = LE_16(&buf[in]);
 207             in += 2;
 208             SE_16BIT(predictor[1])
 209             output_samples[out++] = predictor[1];
 210         }
 211
 212         while (in < buf_size) {
 213             predictor[channel_number] += interplay_delta_table[buf[in++]];
 214             SATURATE_S16(predictor[channel_number]);
 215             output_samples[out++] = predictor[channel_number];
 216
 217             /* toggle channel */
 218             channel_number ^= s->channels - 1;
 219         }
 220
 221         break;
 222
 223     case CODEC_ID_XAN_DPCM:
 224         in = 0;
 225         shift[0] = shift[1] = 4;
 226         predictor[0] = LE_16(&buf[in]);
 227         in += 2;
 228         SE_16BIT(predictor[0]);
 229         if (s->channels == 2) {
 230             predictor[1] = LE_16(&buf[in]);
 231             in += 2;
 232             SE_16BIT(predictor[1]);
 233         }
 234
 235         while (in < buf_size) {
 236             byte = buf[in++];
 237             diff = (byte & 0xFC) << 8;
 238             if ((byte & 0x03) == 3)
 239                 shift[channel_number]++;
 240             else
 241                 shift[channel_number] -= (2 * (byte & 3));
 242             /* saturate the shifter to a lower limit of 0 */
 243             if (shift[channel_number] < 0)
 244                 shift[channel_number] = 0;
 245
 246             diff >>= shift[channel_number];
 247             predictor[channel_number] += diff;
 248
 249             SATURATE_S16(predictor[channel_number]);
 250             output_samples[out++] = predictor[channel_number];
 251
 252             /* toggle channel */
 253             channel_number ^= s->channels - 1;
 254         }
 255         break;
 256     case CODEC_ID_SOL_DPCM:
 257         in = 0;
 258         if (avctx->codec_tag != 3) {
 259             while (in < buf_size) {
 260                 int n1, n2;
 261                 n1 = (buf[in] >> 4) & 0xF;
 262                 n2 = buf[in++] & 0xF;
 263                 s->sample[0] += s->sol_table[n1];
 264                  if (s->sample[0] < 0) s->sample[0] = 0;
 265                 if (s->sample[0] > 255) s->sample[0] = 255;
 266                 output_samples[out++] = (s->sample[0] - 128) << 8;
 267                 s->sample[s->channels - 1] += s->sol_table[n2];
 268                 if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0;
 269                 if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255;
 270                 output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8;
 271             }
 272         } else {
 273             while (in < buf_size) {
 274                 int n;
 275                 n = buf[in++];
 276                 if (n & 0x80) s->sample[channel_number] -= s->sol_table[n & 0x7F];
 277                 else s->sample[channel_number] += s->sol_table[n & 0x7F];
 278                 SATURATE_S16(s->sample[channel_number]);
 279                 output_samples[out++] = s->sample[channel_number];
 280                 /* toggle channel */
 281                 channel_number ^= s->channels - 1;
 282             }
 283         }
 284         break;
 285     }
 286
 287     *data_size = out * sizeof(short);
 288     return buf_size;
 289 }
 290
 291 AVCodec roq_dpcm_decoder = {
 292     "roq_dpcm",
 293     CODEC_TYPE_AUDIO,
 294     CODEC_ID_ROQ_DPCM,
 295     sizeof(DPCMContext),
 296     dpcm_decode_init,
 297     NULL,
 298     NULL,
 299     dpcm_decode_frame,
 300 };
 301
 302 AVCodec interplay_dpcm_decoder = {
 303     "interplay_dpcm",
 304     CODEC_TYPE_AUDIO,
 305     CODEC_ID_INTERPLAY_DPCM,
 306     sizeof(DPCMContext),
 307     dpcm_decode_init,
 308     NULL,
 309     NULL,
 310     dpcm_decode_frame,
 311 };
 312
 313 AVCodec xan_dpcm_decoder = {
 314     "xan_dpcm",
 315     CODEC_TYPE_AUDIO,
 316     CODEC_ID_XAN_DPCM,
 317     sizeof(DPCMContext),
 318     dpcm_decode_init,
 319     NULL,
 320     NULL,
 321     dpcm_decode_frame,
 322 };
 323
 324 AVCodec sol_dpcm_decoder = {
 325     "sol_dpcm",
 326     CODEC_TYPE_AUDIO,
 327     CODEC_ID_SOL_DPCM,
 328     sizeof(DPCMContext),
 329     dpcm_decode_init,
 330     NULL,
 331     NULL,
 332     dpcm_decode_frame,
 333 };