Statistics
| Branch: | Revision:

ffmpeg / libavcodec / ra144.c @ 9085af07

History | View | Annotate | Download (12.5 KB)

1
/*
2
 * Real Audio 1.0 (14.4K)
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
#include "avcodec.h"
21
#include "ra144.h"
22

    
23
#define DATABLOCK1        20                        /* size of 14.4 input block in bytes */
24
#define DATACHUNK1        1440                        /* size of 14.4 input chunk in bytes */
25
#define AUDIOBLOCK        160                        /* size of output block in 16-bit words (320 bytes) */
26
#define AUDIOBUFFER        12288                        /* size of output buffer in 16-bit words (24576 bytes) */
27
/* consts */
28
#define NBLOCKS                4                                /* number of segments within a block */
29
#define BLOCKSIZE        40                                /* (quarter) block size in 16-bit words (80 bytes) */
30
#define HALFBLOCK        20                                /* BLOCKSIZE/2 */
31
#define BUFFERSIZE        146                                /* for do_output */
32

    
33

    
34
/* internal globals */
35
typedef struct {
36
        unsigned int         resetflag, val, oldval;
37
        unsigned int         unpacked[28];                /* buffer for unpacked input */
38
        unsigned int        *iptr;                                /* pointer to current input (from unpacked) */
39
        unsigned int         gval;
40
        unsigned short        *gsp;
41
        unsigned int         gbuf1[8];
42
        unsigned short         gbuf2[120];
43
        signed   short         output_buffer[40];
44
        unsigned int        *decptr;                        /* decoder ptr */
45
        signed   short        *decsp;
46

    
47
        /* the swapped buffers */
48
        unsigned int         swapb1a[10];
49
        unsigned int         swapb2a[10];
50
        unsigned int         swapb1b[10];
51
        unsigned int         swapb2b[10];
52
        unsigned int        *swapbuf1;
53
        unsigned int        *swapbuf2;
54
        unsigned int        *swapbuf1alt;
55
        unsigned int        *swapbuf2alt;
56

    
57
        unsigned int buffer[5];
58
        unsigned short int buffer_2[148];
59
        unsigned short int buffer_a[40];
60
        unsigned short int buffer_b[40];
61
        unsigned short int buffer_c[40];
62
        unsigned short int buffer_d[40];
63

    
64
        unsigned short int work[50];
65
        unsigned short *sptr;
66

    
67
        int buffer1[10];
68
        int buffer2[10];
69

    
70
        signed short wavtable1[2304];
71
        unsigned short wavtable2[2304];
72
} Real144_internal;
73

    
74
static int ra144_decode_init(AVCodecContext * avctx)
75
{
76
        Real144_internal *glob=avctx->priv_data;
77

    
78
        memset(glob,0,sizeof(Real144_internal));
79
        glob->resetflag=1;
80
        glob->swapbuf1=glob->swapb1a;
81
        glob->swapbuf2=glob->swapb2a;
82
        glob->swapbuf1alt=glob->swapb1b;
83
        glob->swapbuf2alt=glob->swapb2b;
84

    
85
        memcpy(glob->wavtable1,wavtable1,sizeof(wavtable1));
86
        memcpy(glob->wavtable2,wavtable2,sizeof(wavtable2));
87

    
88
        return 0;
89
}
90

    
91
static void final(Real144_internal *glob, short *i1, short *i2, void *out, int *statbuf, int len);
92
static void add_wav(Real144_internal *glob, int n, int f, int m1, int m2, int m3, short *s1, short *s2, short *s3, short *dest);
93
static int irms(short *data, int factor);
94
static void rotate_block(short *source, short *target, int offset);
95
/* lookup square roots in table */
96
static int t_sqrt(unsigned int x)
97
{
98
  int s=0;
99
  while (x>0xfff) { s++; x=x>>2; }
100
  return (sqrt_table[x]<<s)<<2;
101
}
102

    
103
/* do 'voice' */
104
static void do_voice(int *a1, int *a2)
105
{
106
  int buffer[10];
107
  int *b1,*b2;
108
  int x,y;
109
  int *ptr,*tmp;
110
  
111
  b1=buffer;
112
  b2=a2;
113
  
114
  for (x=0;x<10;x++) {
115
    b1[x]=(*a1)<<4;
116

    
117
    if(x>0) {
118
      ptr=b2+x;
119
      for (y=0;y<=x-1;y++)
120
        b1[y]=(((*a1)*(*(--ptr)))>>12)+b2[y];
121
    }
122
    tmp=b1;
123
    b1=b2;
124
    b2=tmp;
125
    a1++;
126
  }  
127
  ptr=a2+10;
128
  while (ptr>a2) (*a2++)>>=4;
129
}
130

    
131

    
132
/* do quarter-block output */
133
static void do_output_subblock(Real144_internal *glob, int x)
134
{
135
  int a,b,c,d,e,f,g;
136

    
137
  if (x==1) memset(glob->buffer,0,20);
138
  if ((*glob->iptr)==0) a=0;
139
  else a=(*glob->iptr)+HALFBLOCK-1;
140
  glob->iptr++;
141
  b=*(glob->iptr++);
142
  c=*(glob->iptr++);
143
  d=*(glob->iptr++);
144
  if (a) rotate_block(glob->buffer_2,glob->buffer_a,a);
145
  memcpy(glob->buffer_b,etable1+b*BLOCKSIZE,BLOCKSIZE*2);
146
  e=((ftable1[b]>>4)*glob->gval)>>8;
147
  memcpy(glob->buffer_c,etable2+c*BLOCKSIZE,BLOCKSIZE*2);
148
  f=((ftable2[c]>>4)*glob->gval)>>8;
149
  if (a) g=irms(glob->buffer_a,glob->gval)>>12;
150
  else g=0;
151
  add_wav(glob,d,a,g,e,f,glob->buffer_a,glob->buffer_b,glob->buffer_c,glob->buffer_d);
152
  memmove(glob->buffer_2,glob->buffer_2+BLOCKSIZE,(BUFFERSIZE-BLOCKSIZE)*2);
153
  memcpy(glob->buffer_2+BUFFERSIZE-BLOCKSIZE,glob->buffer_d,BLOCKSIZE*2);
154
  final(glob,glob->gsp,glob->buffer_d,glob->output_buffer,glob->buffer,BLOCKSIZE);
155
}
156

    
157
/* rotate block */
158
static void rotate_block(short *source, short *target, int offset)
159
{
160
  short *end;
161
  short *ptr1;
162
  short *ptr2;
163
  short *ptr3;
164
  ptr2=source+BUFFERSIZE;
165
  ptr3=ptr1=ptr2-offset;
166
  end=target+BLOCKSIZE;
167
  while (target<end) {
168
    *(target++)=*(ptr3++);
169
    if (ptr3==ptr2) ptr3=ptr1;
170
  }
171
}
172

    
173
/* inverse root mean square */
174
static int irms(short *data, int factor)
175
{
176
  short *p1,*p2;
177
  unsigned int sum;
178
  p2=(p1=data)+BLOCKSIZE;
179
  for (sum=0;p2>p1;p1++) sum+=(*p1)*(*p1);
180
  if (sum==0) return 0; /* OOPS - division by zero */
181
  return (0x20000000/(t_sqrt(sum)>>8))*factor;
182
}
183

    
184
/* multiply/add wavetable */
185
static void add_wav(Real144_internal *glob, int n, int f, int m1, int m2, int m3, short *s1, short *s2, short *s3, short *dest)
186
{
187
  int a,b,c;
188
  int x;
189
  short *ptr,*ptr2;
190

    
191
  ptr=glob->wavtable1+n*9;
192
  ptr2=glob->wavtable2+n*9;
193
  if (f!=0) {
194
    a=((*ptr)*m1)>>((*ptr2)+1); 
195
  } else {
196
    a=0;
197
  }
198
  ptr++;ptr2++;
199
  b=((*ptr)*m2)>>((*ptr2)+1);
200
  ptr++;ptr2++;
201
  c=((*ptr)*m3)>>((*ptr2)+1);
202
  ptr2=(ptr=dest)+BLOCKSIZE;
203
  if (f!=0)
204
    while (ptr<ptr2)
205
      *(ptr++)=((*(s1++))*a+(*(s2++))*b+(*(s3++))*c)>>12;
206
  else
207
    while (ptr<ptr2)
208
      *(ptr++)=((*(s2++))*b+(*(s3++))*c)>>12;
209
}
210

    
211

    
212
static void final(Real144_internal *glob, short *i1, short *i2, void *out, int *statbuf, int len)
213
{
214
  int x,sum;
215
  int buffer[10];
216
  short *ptr;
217
  short *ptr2;
218

    
219
  memcpy(glob->work,statbuf,20);
220
  memcpy(glob->work+10,i2,len*2);
221

    
222
  buffer[9]=i1[0];
223
  buffer[8]=i1[1];
224
  buffer[7]=i1[2];
225
  buffer[6]=i1[3];
226
  buffer[5]=i1[4];
227
  buffer[4]=i1[5];
228
  buffer[3]=i1[6];
229
  buffer[2]=i1[7];
230
  buffer[1]=i1[8];
231
  buffer[0]=i1[9];
232

    
233
  ptr2=(ptr=glob->work)+len;
234
  while (ptr<ptr2) {
235
    for(sum=0,x=0;x<=9;x++)
236
      sum+=buffer[x]*(ptr[x]);
237
    sum=sum>>12;
238
    x=ptr[10]-sum;
239
    if (x<-32768 || x>32767)
240
    {
241
      memset(out,0,len*2);
242
      memset(statbuf,0,20);
243
      return;
244
    }
245
    ptr[10]=x;
246
    ptr++;
247
  }
248
  memcpy(out,ptr+10-len,len*2);
249
  memcpy(statbuf,ptr,20);
250
}
251

    
252
/* Decode 20-byte input */
253
static void unpack_input(unsigned char *input, unsigned int *output)
254
{
255
  unsigned int outbuffer[28];
256
  unsigned short inbuffer[10];
257
  unsigned int x;
258
  unsigned int *ptr;
259

    
260
  /* fix endianness */
261
  for (x=0;x<20;x+=2)
262
    inbuffer[x/2]=(input[x]<<8)+input[x+1];
263

    
264
  /* unpack */
265
  ptr=outbuffer;
266
  *(ptr++)=27;
267
  *(ptr++)=(inbuffer[0]>>10)&0x3f;
268
  *(ptr++)=(inbuffer[0]>>5)&0x1f;
269
  *(ptr++)=inbuffer[0]&0x1f;
270
  *(ptr++)=(inbuffer[1]>>12)&0xf;
271
  *(ptr++)=(inbuffer[1]>>8)&0xf;
272
  *(ptr++)=(inbuffer[1]>>5)&7;
273
  *(ptr++)=(inbuffer[1]>>2)&7;
274
  *(ptr++)=((inbuffer[1]<<1)&6)|((inbuffer[2]>>15)&1);
275
  *(ptr++)=(inbuffer[2]>>12)&7;
276
  *(ptr++)=(inbuffer[2]>>10)&3;
277
  *(ptr++)=(inbuffer[2]>>5)&0x1f;
278
  *(ptr++)=((inbuffer[2]<<2)&0x7c)|((inbuffer[3]>>14)&3);
279
  *(ptr++)=(inbuffer[3]>>6)&0xff;
280
  *(ptr++)=((inbuffer[3]<<1)&0x7e)|((inbuffer[4]>>15)&1);
281
  *(ptr++)=(inbuffer[4]>>8)&0x7f;
282
  *(ptr++)=(inbuffer[4]>>1)&0x7f;
283
  *(ptr++)=((inbuffer[4]<<7)&0x80)|((inbuffer[5]>>9)&0x7f);
284
  *(ptr++)=(inbuffer[5]>>2)&0x7f;
285
  *(ptr++)=((inbuffer[5]<<5)&0x60)|((inbuffer[6]>>11)&0x1f);
286
  *(ptr++)=(inbuffer[6]>>4)&0x7f;
287
  *(ptr++)=((inbuffer[6]<<4)&0xf0)|((inbuffer[7]>>12)&0xf);
288
  *(ptr++)=(inbuffer[7]>>5)&0x7f;
289
  *(ptr++)=((inbuffer[7]<<2)&0x7c)|((inbuffer[8]>>14)&3);
290
  *(ptr++)=(inbuffer[8]>>7)&0x7f;
291
  *(ptr++)=((inbuffer[8]<<1)&0xfe)|((inbuffer[9]>>15)&1);
292
  *(ptr++)=(inbuffer[9]>>8)&0x7f;
293
  *(ptr++)=(inbuffer[9]>>1)&0x7f;
294

    
295
  *(output++)=outbuffer[11];
296
  for (x=1;x<11;*(output++)=outbuffer[x++]);
297
  ptr=outbuffer+12;
298
  for (x=0;x<16;x+=4)
299
  {
300
    *(output++)=ptr[x];
301
    *(output++)=ptr[x+2];
302
    *(output++)=ptr[x+3];
303
    *(output++)=ptr[x+1];    
304
  }
305
}
306

    
307
static unsigned int rms(int *data, int f)
308
{
309
  int *c;
310
  int x;
311
  int d;
312
  unsigned int res;
313
  int b;
314

    
315
  c=data;
316
  b=0;
317
  res=0x10000;
318
  for (x=0;x<10;x++)
319
  {
320
    res=(((0x1000000-(*c)*(*c))>>12)*res)>>12;
321
    if (res==0) return 0;
322
    if (res<=0x3fff)
323
    {
324
      while (res<=0x3fff)
325
      {
326
        b++;
327
        res<<=2;
328
      }
329
    } else {
330
      if (res>0x10000)
331
        return 0; /* We're screwed, might as well go out with a bang. :P */
332
    }
333
    c++;
334
  }
335
  if (res>0) res=t_sqrt(res);
336

    
337
  res>>=(b+10);
338
  res=(res*f)>>10;
339
  return res;
340
}
341

    
342
static void dec1(Real144_internal *glob, int *data, int *inp, int n, int f)
343
{
344
  short *ptr,*end;
345

    
346
  *(glob->decptr++)=rms(data,f);
347
  glob->decptr++;
348
  end=(ptr=glob->decsp)+(n*10);
349
  while (ptr<end) *(ptr++)=*(inp++);
350
}
351

    
352
static int eq(Real144_internal *glob, short *in, int *target)
353
{
354
  int retval;
355
  int a;
356
  int b;
357
  int c;
358
  unsigned int u;
359
  short *sptr;
360
  int *ptr1,*ptr2,*ptr3;
361
  int *bp1,*bp2,*temp;
362

    
363
  retval=0;
364
  bp1=glob->buffer1;
365
  bp2=glob->buffer2;
366
  ptr2=(ptr3=glob->buffer2)+9;
367
  sptr=in;
368
  while (ptr2>=ptr3)
369
    *(ptr3++)=*(sptr++);
370

    
371
  target+=9;
372
  a=bp2[9];
373
  *target=a;
374
  if (a+0x1000>0x1fff)
375
    return 0; /* We're screwed, might as well go out with a bang. :P */
376
  c=8;u=a;
377
  while (c>=0)
378
  {
379
    if (u==0x1000) u++;
380
    if (u==0xfffff000) u--;
381
    b=0x1000-((u*u)>>12);
382
    if (b==0) b++;
383
    ptr2=bp1;
384
    ptr1=(ptr3=bp2)+c;
385
    for (u=0;u<=c;u++)
386
      *(ptr2++)=((*(ptr3++)-(((*target)*(*(ptr1--)))>>12))*(0x1000000/b))>>12;
387
    *(--target)=u=bp1[(c--)];
388
    if ((u+0x1000)>0x1fff) retval=1;
389
    temp=bp2;
390
    bp2=bp1;
391
    bp1=temp;
392
  }
393
  return retval;
394
}
395

    
396
static void dec2(Real144_internal *glob, int *data, int *inp, int n, int f, int *inp2, int l)
397
{
398
  unsigned int *ptr1,*ptr2;
399
  int work[10];
400
  int a,b;
401
  int x;
402
  int result;
403

    
404
  if(l+1<NBLOCKS/2) a=NBLOCKS-(l+1);
405
  else a=l+1;
406
  b=NBLOCKS-a;
407
  if (l==0)
408
  {
409
    glob->decsp=glob->sptr=glob->gbuf2;
410
    glob->decptr=glob->gbuf1;
411
  }
412
  ptr1=inp;
413
  ptr2=inp2;
414
  for (x=0;x<10*n;x++)
415
    *(glob->sptr++)=(a*(*ptr1++)+b*(*ptr2++))>>2;
416
  result=eq(glob,glob->decsp,work);
417
  if (result==1)
418
  {
419
    dec1(glob,data,inp,n,f);
420
  } else {
421
    *(glob->decptr++)=rms(work,f);
422
    glob->decptr++;
423
  }
424
  glob->decsp+=n*10;
425
}
426

    
427
/* Uncompress one block (20 bytes -> 160*2 bytes) */
428
static int ra144_decode_frame(AVCodecContext * avctx,
429
            void *data, int *data_size,
430
            uint8_t * buf, int buf_size)
431
{
432
  unsigned int a,b,c;
433
  long s;
434
  signed short *shptr;
435
  unsigned int *lptr,*temp;
436
  const short **dptr;
437
  void *datao;
438
  Real144_internal *glob=avctx->priv_data;
439

    
440
  datao = data;
441
  unpack_input(buf,glob->unpacked);
442
  
443
  glob->iptr=glob->unpacked;
444
  glob->val=decodetable[0][(*(glob->iptr++))<<1];
445

    
446
  dptr=decodetable+1;
447
  lptr=glob->swapbuf1;
448
  while (lptr<glob->swapbuf1+10)
449
    *(lptr++)=(*(dptr++))[(*(glob->iptr++))<<1];
450

    
451
  do_voice(glob->swapbuf1,glob->swapbuf2);
452

    
453
  a=t_sqrt(glob->val*glob->oldval)>>12;
454

    
455
  for (c=0;c<NBLOCKS;c++) {
456
    if (c==(NBLOCKS-1)) {
457
      dec1(glob,glob->swapbuf1,glob->swapbuf2,3,glob->val);
458
    } else {
459
      if (c*2==(NBLOCKS-2)) {
460
        if (glob->oldval<glob->val) {
461
          dec2(glob,glob->swapbuf1,glob->swapbuf2,3,a,glob->swapbuf2alt,c);
462
        } else {
463
          dec2(glob,glob->swapbuf1alt,glob->swapbuf2alt,3,a,glob->swapbuf2,c);
464
        }
465
      } else {
466
        if (c*2<(NBLOCKS-2)) {
467
          dec2(glob,glob->swapbuf1alt,glob->swapbuf2alt,3,glob->oldval,glob->swapbuf2,c);
468
        } else {
469
          dec2(glob,glob->swapbuf1,glob->swapbuf2,3,glob->val,glob->swapbuf2alt,c);
470
        }
471
      }
472
    }
473
  }
474

    
475
  /* do output */
476
  for (b=0,c=0;c<4;c++) {
477
    glob->gval=glob->gbuf1[c*2];
478
    glob->gsp=glob->gbuf2+b;
479
    do_output_subblock(glob,glob->resetflag);
480
    glob->resetflag=0;
481

    
482
    shptr=glob->output_buffer;
483
    while (shptr<glob->output_buffer+BLOCKSIZE) {
484
      s=*(shptr++)<<2;
485
      *((int16_t *)data)=s;
486
      if (s>32767) *((int16_t *)data)=32767;
487
      if (s<-32767) *((int16_t *)data)=-32768;
488
      ((int16_t *)data)++;
489
    }
490
    b+=30;
491
  }
492

    
493
  glob->oldval=glob->val;
494
  temp=glob->swapbuf1alt;
495
  glob->swapbuf1alt=glob->swapbuf1;
496
  glob->swapbuf1=temp;
497
  temp=glob->swapbuf2alt;
498
  glob->swapbuf2alt=glob->swapbuf2;
499
  glob->swapbuf2=temp;
500
  *data_size=data-datao;
501
  return 20;
502
}
503

    
504

    
505
AVCodec ra_144_decoder =
506
{
507
    "real_144",
508
    CODEC_TYPE_AUDIO,
509
    CODEC_ID_RA_144,
510
    sizeof(Real144_internal),
511
    ra144_decode_init,
512
    NULL,
513
    NULL,
514
    ra144_decode_frame,
515
};