quicktime/ulaw.c

   1 #include "funcprotos.h"
   2 #include "quicktime.h"
   3 #include "ulaw.h"
   4 #include <stdint.h>
   5
   6 typedef struct
   7 {
   8         float *ulawtofloat_table;
   9         float *ulawtofloat_ptr;
  10         int16_t *ulawtoint16_table;
  11         int16_t *ulawtoint16_ptr;
  12         unsigned char *int16toulaw_table;
  13         unsigned char *int16toulaw_ptr;
  14         unsigned char *read_buffer;
  15         long read_size;
  16 } quicktime_ulaw_codec_t;
  17
  18 /* ==================================== private for ulaw */
  19
  20 #define uBIAS 0x84
  21 #define uCLIP 32635
  22
  23 int ulaw_init_ulawtoint16(quicktime_t *file, int track)
  24 {
  25         int i;
  26         quicktime_audio_map_t *atrack = &(file->atracks[track]);
  27         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)atrack->codec)->priv;
  28
  29 /* We use the floating point table to get values for the 16 bit table */
  30         ulaw_init_ulawtofloat(file, track);
  31         if(!codec->ulawtoint16_table)
  32         {
  33                 codec->ulawtoint16_table = malloc(sizeof(int16_t) * 256);
  34                 codec->ulawtoint16_ptr = codec->ulawtoint16_table;
  35
  36                 for(i = 0; i < 256; i++)
  37                 {
  38                         codec->ulawtoint16_table[i] = (int)(32768 * codec->ulawtofloat_ptr[i]);
  39                 }
  40         }
  41         return 0;
  42 }
  43
  44 int16_t ulaw_bytetoint16(quicktime_ulaw_codec_t *codec, unsigned char input)
  45 {
  46         return codec->ulawtoint16_ptr[input];
  47 }
  48
  49 int ulaw_init_ulawtofloat(quicktime_t *file, int track)
  50 {
  51         int i;
  52         float value;
  53         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)file->atracks[track].codec)->priv;
  54
  55         if(!codec->ulawtofloat_table)
  56         {
  57         static int exp_lut[8] = { 0, 132, 396, 924, 1980, 4092, 8316, 16764 };
  58         int sign, exponent, mantissa, sample;
  59                 unsigned char ulawbyte;
  60
  61                 codec->ulawtofloat_table = malloc(sizeof(float) * 256);
  62                 codec->ulawtofloat_ptr = codec->ulawtofloat_table;
  63                 for(i = 0; i < 256; i++)
  64                 {
  65                         ulawbyte = (unsigned char)i;
  66                 ulawbyte = ~ulawbyte;
  67                 sign = (ulawbyte & 0x80);
  68                 exponent = (ulawbyte >> 4) & 0x07;
  69                 mantissa = ulawbyte & 0x0F;
  70                 sample = exp_lut[exponent] + (mantissa << (exponent + 3));
  71                 if(sign != 0) sample = -sample;
  72
  73                         codec->ulawtofloat_ptr[i] = (float)sample / 32768;
  74                 }
  75         }
  76         return 0;
  77 }
  78
  79 float ulaw_bytetofloat(quicktime_ulaw_codec_t *codec, unsigned char input)
  80 {
  81         return codec->ulawtofloat_ptr[input];
  82 }
  83
  84 int ulaw_init_int16toulaw(quicktime_t *file, int track)
  85 {
  86         quicktime_audio_map_t *atrack = &(file->atracks[track]);
  87         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)atrack->codec)->priv;
  88
  89         if(!codec->int16toulaw_table)
  90         {
  91         int sign, exponent, mantissa;
  92         unsigned char ulawbyte;
  93                 int sample;
  94                 int i;
  95         int exp_lut[256] = {0,0,1,1,2,2,2,2,3,3,3,3,3,3,3,3,
  96                                4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
  97                                5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
  98                                5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
  99                                6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
 100                                6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
 101                                6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
 102                                6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
 103                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
 104                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
 105                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
 106                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
 107                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
 108                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
 109                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
 110                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7};
 111
 112                 codec->int16toulaw_table = malloc(65536);
 113                 codec->int16toulaw_ptr = codec->int16toulaw_table + 32768;
 114
 115                 for(i = -32768; i < 32768; i++)
 116                 {
 117                         sample = i;
 118 /* Get the sample into sign-magnitude. */
 119                 sign = (sample >> 8) & 0x80;            /* set aside the sign */
 120                 if(sign != 0) sample = -sample;         /* get magnitude */
 121                 if(sample > uCLIP) sample = uCLIP;              /* clip the magnitude */
 122
 123 /* Convert from 16 bit linear to ulaw. */
 124                 sample = sample + uBIAS;
 125                     exponent = exp_lut[(sample >> 7) & 0xFF];
 126                     mantissa = (sample >> (exponent + 3)) & 0x0F;
 127                     ulawbyte = ~(sign | (exponent << 4) | mantissa);
 128 #ifdef ZEROTRAP
 129                     if (ulawbyte == 0) ulawbyte = 0x02;     /* optional CCITT trap */
 130 #endif
 131
 132                     codec->int16toulaw_ptr[i] = ulawbyte;
 133                 }
 134         }
 135         return 0;
 136 }
 137
 138 float ulaw_int16tobyte(quicktime_ulaw_codec_t *codec, int16_t input)
 139 {
 140         return codec->int16toulaw_ptr[input];
 141 }
 142
 143 float ulaw_floattobyte(quicktime_ulaw_codec_t *codec, float input)
 144 {
 145         return codec->int16toulaw_ptr[(int)(input * 32768)];
 146 }
 147
 148
 149 int ulaw_get_read_buffer(quicktime_t *file, int track, long samples)
 150 {
 151         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)file->atracks[track].codec)->priv;
 152
 153         if(codec->read_buffer && codec->read_size != samples)
 154         {
 155                 free(codec->read_buffer);
 156                 codec->read_buffer = 0;
 157         }
 158
 159         if(!codec->read_buffer)
 160         {
 161                 int64_t bytes = samples * file->atracks[track].channels;
 162                 codec->read_size = samples;
 163                 if(!(codec->read_buffer = malloc(bytes))) return 1;
 164         }
 165         return 0;
 166 }
 167
 168 int ulaw_delete_tables(quicktime_audio_map_t *atrack)
 169 {
 170         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)atrack->codec)->priv;
 171
 172         if(codec->ulawtofloat_table)
 173         {
 174                 free(codec->ulawtofloat_table);
 175         }
 176         if(codec->ulawtoint16_table)
 177         {
 178                 free(codec->ulawtoint16_table);
 179         }
 180         if(codec->int16toulaw_table)
 181         {
 182                 free(codec->int16toulaw_table);
 183         }
 184         if(codec->read_buffer) free(codec->read_buffer);
 185         codec->int16toulaw_table = 0;
 186         codec->ulawtoint16_table = 0;
 187         codec->ulawtofloat_table = 0;
 188         codec->read_buffer = 0;
 189         codec->read_size = 0;
 190         return 0;
 191 }
 192
 193 /* =================================== public for ulaw */
 194
 195 static int quicktime_delete_codec_ulaw(quicktime_audio_map_t *atrack)
 196 {
 197         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)atrack->codec)->priv;
 198
 199         ulaw_delete_tables(atrack);
 200         free(codec);
 201         return 0;
 202 }
 203
 204 static int quicktime_decode_ulaw(quicktime_t *file,
 205                                         int16_t *output_i,
 206                                         float *output_f,
 207                                         long samples,
 208                                         int track,
 209                                         int channel)
 210 {
 211         int result = 0;
 212         long i;
 213         quicktime_audio_map_t *track_map = &(file->atracks[track]);
 214         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)track_map->codec)->priv;
 215
 216         result = ulaw_get_read_buffer(file, track, samples);
 217
 218         if(output_f) result += ulaw_init_ulawtofloat(file, track);
 219         if(output_i) result += ulaw_init_ulawtoint16(file, track);
 220
 221         if(!result)
 222         {
 223                 result = !quicktime_read_audio(file, codec->read_buffer, samples, track);
 224 // Undo increment since this is done in codecs.c
 225                 track_map->current_position -= samples;
 226
 227 /*printf("quicktime_decode_ulaw %d\n", result); */
 228                 if(!result)
 229                 {
 230                         if(output_f)
 231                         {
 232                                 unsigned char *input = &(codec->read_buffer[channel]);
 233                                 float *output_ptr = output_f;
 234                                 float *output_end = output_f + samples;
 235                                 int step = file->atracks[track].channels;
 236
 237                                 while(output_ptr < output_end)
 238                                 {
 239                                         *output_ptr++ = ulaw_bytetofloat(codec, *input);
 240                                         input += step;
 241                                 }
 242                         }
 243                         else
 244                         if(output_i)
 245                         {
 246                                 unsigned char *input = &(codec->read_buffer[channel]);
 247                                 int16_t *output_ptr = output_i;
 248                                 int16_t *output_end = output_i + samples;
 249                                 int step = file->atracks[track].channels;
 250
 251                                 while(output_ptr < output_end)
 252                                 {
 253                                         *output_ptr++ = ulaw_bytetoint16(codec, *input);
 254                                         input += step;
 255                                 }
 256                         }
 257                 }
 258         }
 259
 260         return result;
 261 }
 262
 263 static int quicktime_encode_ulaw(quicktime_t *file,
 264                                                         int16_t **input_i,
 265                                                         float **input_f,
 266                                                         int track,
 267                                                         long samples)
 268 {
 269         int result = 0;
 270         int channel, step;
 271         int64_t i;
 272         quicktime_ulaw_codec_t *codec = ((quicktime_codec_t*)file->atracks[track].codec)->priv;
 273         quicktime_atom_t chunk_atom;
 274         quicktime_audio_map_t *track_map = &file->atracks[track];
 275         quicktime_trak_t *trak = track_map->track;
 276
 277         result = ulaw_init_int16toulaw(file, track);
 278         result += ulaw_get_read_buffer(file, track, samples);
 279
 280         if(!result)
 281         {
 282                 step = file->atracks[track].channels;
 283
 284                 if(input_f)
 285                 {
 286                         for(channel = 0; channel < file->atracks[track].channels; channel++)
 287                         {
 288                                 float *input_ptr = input_f[channel];
 289                                 float *input_end = input_f[channel] + samples;
 290                                 unsigned char *output = codec->read_buffer + channel;
 291
 292                                 while(input_ptr < input_end)
 293                                 {
 294                                         *output = ulaw_floattobyte(codec, *input_ptr++);
 295                                         output += step;
 296                                 }
 297                         }
 298                 }
 299                 else
 300                 if(input_i)
 301                 {
 302                         for(channel = 0; channel < file->atracks[track].channels; channel++)
 303                         {
 304                                 int16_t *input_ptr = input_i[channel];
 305                                 int16_t *input_end = input_i[channel] + samples;
 306                                 unsigned char *output = codec->read_buffer + channel;
 307
 308                                 while(input_ptr < input_end)
 309                                 {
 310                                         *output = ulaw_int16tobyte(codec, *input_ptr++);
 311                                         output += step;
 312                                 }
 313                         }
 314                 }
 315
 316                 quicktime_write_chunk_header(file, trak, &chunk_atom);
 317                 result = quicktime_write_data(file,
 318                         codec->read_buffer,
 319                         samples * file->atracks[track].channels);
 320                 quicktime_write_chunk_footer(file,
 321                                                 trak,
 322                                                 track_map->current_chunk,
 323                                                 &chunk_atom,
 324                                                 samples);
 325
 326 /* defeat fwrite's return */
 327                 if(result)
 328                         result = 0;
 329                 else
 330                         result = 1;
 331
 332                 file->atracks[track].current_chunk++;
 333         }
 334
 335         return result;
 336 }
 337
 338
 339 void quicktime_init_codec_ulaw(quicktime_audio_map_t *atrack)
 340 {
 341         quicktime_codec_t *codec_base = (quicktime_codec_t*)atrack->codec;
 342         quicktime_ulaw_codec_t *codec;
 343
 344 /* Init public items */
 345         codec_base->priv = calloc(1, sizeof(quicktime_ulaw_codec_t));
 346         codec_base->delete_acodec = quicktime_delete_codec_ulaw;
 347         codec_base->decode_video = 0;
 348         codec_base->encode_video = 0;
 349         codec_base->decode_audio = quicktime_decode_ulaw;
 350         codec_base->encode_audio = quicktime_encode_ulaw;
 351         codec_base->fourcc = QUICKTIME_ULAW;
 352         codec_base->title = "uLaw";
 353         codec_base->desc = "uLaw";
 354         codec_base->wav_id = 0x07;
 355
 356 /* Init private items */
 357         codec = ((quicktime_codec_t*)atrack->codec)->priv;
 358 }