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ffmpeg / libavcodec / ra144.c @ 68ca24e6

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/*
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 * Real Audio 1.0 (14.4K)
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 * Copyright (c) 2003 the ffmpeg project
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 */
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#include "avcodec.h"
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#include "ra144.h"
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#define DATABLOCK1        20                        /* size of 14.4 input block in bytes */
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#define DATACHUNK1        1440                        /* size of 14.4 input chunk in bytes */
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#define AUDIOBLOCK        160                        /* size of output block in 16-bit words (320 bytes) */
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#define AUDIOBUFFER        12288                        /* size of output buffer in 16-bit words (24576 bytes) */
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/* consts */
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#define NBLOCKS                4                                /* number of segments within a block */
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#define BLOCKSIZE        40                                /* (quarter) block size in 16-bit words (80 bytes) */
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#define HALFBLOCK        20                                /* BLOCKSIZE/2 */
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#define BUFFERSIZE        146                                /* for do_output */
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33

    
34
/* internal globals */
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typedef struct {
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        unsigned int         resetflag, val, oldval;
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        unsigned int         unpacked[28];                /* buffer for unpacked input */
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        unsigned int        *iptr;                                /* pointer to current input (from unpacked) */
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        unsigned int         gval;
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        unsigned short        *gsp;
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        unsigned int         gbuf1[8];
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        unsigned short         gbuf2[120];
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        signed   short         output_buffer[40];
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        unsigned int        *decptr;                        /* decoder ptr */
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        signed   short        *decsp;
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        /* the swapped buffers */
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        unsigned int         swapb1a[10];
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        unsigned int         swapb2a[10];
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        unsigned int         swapb1b[10];
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        unsigned int         swapb2b[10];
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        unsigned int        *swapbuf1;
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        unsigned int        *swapbuf2;
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        unsigned int        *swapbuf1alt;
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        unsigned int        *swapbuf2alt;
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        unsigned int buffer[5];
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        unsigned short int buffer_2[148];
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        unsigned short int buffer_a[40];
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        unsigned short int buffer_b[40];
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        unsigned short int buffer_c[40];
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        unsigned short int buffer_d[40];
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        unsigned short int work[50];
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        unsigned short *sptr;
66

    
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        int buffer1[10];
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        int buffer2[10];
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        signed short wavtable1[2304];
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        unsigned short wavtable2[2304];
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} Real144_internal;
73

    
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static int ra144_decode_init(AVCodecContext * avctx)
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{
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        Real144_internal *glob=avctx->priv_data;
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        memset(glob,0,sizeof(Real144_internal));
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        glob->resetflag=1;
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        glob->swapbuf1=glob->swapb1a;
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        glob->swapbuf2=glob->swapb2a;
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        glob->swapbuf1alt=glob->swapb1b;
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        glob->swapbuf2alt=glob->swapb2b;
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        memcpy(glob->wavtable1,wavtable1,sizeof(wavtable1));
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        memcpy(glob->wavtable2,wavtable2,sizeof(wavtable2));
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        return 0;
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}
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91
static void final(Real144_internal *glob, short *i1, short *i2, void *out, int *statbuf, int len);
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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);
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static int irms(short *data, int factor);
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static void rotate_block(short *source, short *target, int offset);
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/* lookup square roots in table */
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static int t_sqrt(unsigned int x)
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{
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  int s=0;
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  while (x>0xfff) { s++; x=x>>2; }
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  return (sqrt_table[x]<<s)<<2;
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}
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103
/* do 'voice' */
104
static void do_voice(int *a1, int *a2)
105
{
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  int buffer[10];
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  int *b1,*b2;
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  int x,y;
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  int *ptr,*tmp;
110
  
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  b1=buffer;
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  b2=a2;
113
  
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  for (x=0;x<10;x++) {
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    b1[x]=(*a1)<<4;
116

    
117
    if(x>0) {
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      ptr=b2+x;
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      for (y=0;y<=x-1;y++)
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        b1[y]=(((*a1)*(*(--ptr)))>>12)+b2[y];
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    }
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    tmp=b1;
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    b1=b2;
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    b2=tmp;
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    a1++;
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  }  
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  ptr=a2+10;
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  while (ptr>a2) (*a2++)>>=4;
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}
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131

    
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/* do quarter-block output */
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static void do_output_subblock(Real144_internal *glob, int x)
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{
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  int a,b,c,d,e,f,g;
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137
  if (x==1) memset(glob->buffer,0,20);
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  if ((*glob->iptr)==0) a=0;
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  else a=(*glob->iptr)+HALFBLOCK-1;
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  glob->iptr++;
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  b=*(glob->iptr++);
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  c=*(glob->iptr++);
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  d=*(glob->iptr++);
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  if (a) rotate_block(glob->buffer_2,glob->buffer_a,a);
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  memcpy(glob->buffer_b,etable1+b*BLOCKSIZE,BLOCKSIZE*2);
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  e=((ftable1[b]>>4)*glob->gval)>>8;
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  memcpy(glob->buffer_c,etable2+c*BLOCKSIZE,BLOCKSIZE*2);
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  f=((ftable2[c]>>4)*glob->gval)>>8;
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  if (a) g=irms(glob->buffer_a,glob->gval)>>12;
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  else g=0;
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  add_wav(glob,d,a,g,e,f,glob->buffer_a,glob->buffer_b,glob->buffer_c,glob->buffer_d);
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  memmove(glob->buffer_2,glob->buffer_2+BLOCKSIZE,(BUFFERSIZE-BLOCKSIZE)*2);
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  memcpy(glob->buffer_2+BUFFERSIZE-BLOCKSIZE,glob->buffer_d,BLOCKSIZE*2);
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  final(glob,glob->gsp,glob->buffer_d,glob->output_buffer,glob->buffer,BLOCKSIZE);
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}
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/* rotate block */
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static void rotate_block(short *source, short *target, int offset)
159
{
160
  short *end;
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  short *ptr1;
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  short *ptr2;
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  short *ptr3;
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  ptr2=source+BUFFERSIZE;
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  ptr3=ptr1=ptr2-offset;
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  end=target+BLOCKSIZE;
167
  while (target<end) {
168
    *(target++)=*(ptr3++);
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    if (ptr3==ptr2) ptr3=ptr1;
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  }
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}
172

    
173
/* inverse root mean square */
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static int irms(short *data, int factor)
175
{
176
  short *p1,*p2;
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  unsigned int sum;
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  p2=(p1=data)+BLOCKSIZE;
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  for (sum=0;p2>p1;p1++) sum+=(*p1)*(*p1);
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  if (sum==0) return 0; /* OOPS - division by zero */
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  return (0x20000000/(t_sqrt(sum)>>8))*factor;
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}
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/* multiply/add wavetable */
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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
  short *ptr,*ptr2;
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  ptr=glob->wavtable1+n*9;
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  ptr2=glob->wavtable2+n*9;
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  if (f!=0) {
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    a=((*ptr)*m1)>>((*ptr2)+1); 
194
  } else {
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    a=0;
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  }
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  ptr++;ptr2++;
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  b=((*ptr)*m2)>>((*ptr2)+1);
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  ptr++;ptr2++;
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  c=((*ptr)*m3)>>((*ptr2)+1);
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  ptr2=(ptr=dest)+BLOCKSIZE;
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  if (f!=0)
203
    while (ptr<ptr2)
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      *(ptr++)=((*(s1++))*a+(*(s2++))*b+(*(s3++))*c)>>12;
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  else
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    while (ptr<ptr2)
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      *(ptr++)=((*(s2++))*b+(*(s3++))*c)>>12;
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}
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static void final(Real144_internal *glob, short *i1, short *i2, void *out, int *statbuf, int len)
212
{
213
  int x,sum;
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  int buffer[10];
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  short *ptr;
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  short *ptr2;
217

    
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  memcpy(glob->work,statbuf,20);
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  memcpy(glob->work+10,i2,len*2);
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  buffer[9]=i1[0];
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  buffer[8]=i1[1];
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  buffer[7]=i1[2];
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  buffer[6]=i1[3];
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  buffer[5]=i1[4];
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  buffer[4]=i1[5];
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  buffer[3]=i1[6];
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  buffer[2]=i1[7];
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  buffer[1]=i1[8];
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  buffer[0]=i1[9];
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  ptr2=(ptr=glob->work)+len;
233
  while (ptr<ptr2) {
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    for(sum=0,x=0;x<=9;x++)
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      sum+=buffer[x]*(ptr[x]);
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    sum=sum>>12;
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    x=ptr[10]-sum;
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    if (x<-32768 || x>32767)
239
    {
240
      memset(out,0,len*2);
241
      memset(statbuf,0,20);
242
      return;
243
    }
244
    ptr[10]=x;
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    ptr++;
246
  }
247
  memcpy(out,ptr+10-len,len*2);
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  memcpy(statbuf,ptr,20);
249
}
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251
/* Decode 20-byte input */
252
static void unpack_input(unsigned char *input, unsigned int *output)
253
{
254
  unsigned int outbuffer[28];
255
  unsigned short inbuffer[10];
256
  unsigned int x;
257
  unsigned int *ptr;
258

    
259
  /* fix endianness */
260
  for (x=0;x<20;x+=2)
261
    inbuffer[x/2]=(input[x]<<8)+input[x+1];
262

    
263
  /* unpack */
264
  ptr=outbuffer;
265
  *(ptr++)=27;
266
  *(ptr++)=(inbuffer[0]>>10)&0x3f;
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  *(ptr++)=(inbuffer[0]>>5)&0x1f;
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  *(ptr++)=inbuffer[0]&0x1f;
269
  *(ptr++)=(inbuffer[1]>>12)&0xf;
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  *(ptr++)=(inbuffer[1]>>8)&0xf;
271
  *(ptr++)=(inbuffer[1]>>5)&7;
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  *(ptr++)=(inbuffer[1]>>2)&7;
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  *(ptr++)=((inbuffer[1]<<1)&6)|((inbuffer[2]>>15)&1);
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  *(ptr++)=(inbuffer[2]>>12)&7;
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  *(ptr++)=(inbuffer[2]>>10)&3;
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  *(ptr++)=(inbuffer[2]>>5)&0x1f;
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  *(ptr++)=((inbuffer[2]<<2)&0x7c)|((inbuffer[3]>>14)&3);
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  *(ptr++)=(inbuffer[3]>>6)&0xff;
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  *(ptr++)=((inbuffer[3]<<1)&0x7e)|((inbuffer[4]>>15)&1);
280
  *(ptr++)=(inbuffer[4]>>8)&0x7f;
281
  *(ptr++)=(inbuffer[4]>>1)&0x7f;
282
  *(ptr++)=((inbuffer[4]<<7)&0x80)|((inbuffer[5]>>9)&0x7f);
283
  *(ptr++)=(inbuffer[5]>>2)&0x7f;
284
  *(ptr++)=((inbuffer[5]<<5)&0x60)|((inbuffer[6]>>11)&0x1f);
285
  *(ptr++)=(inbuffer[6]>>4)&0x7f;
286
  *(ptr++)=((inbuffer[6]<<4)&0xf0)|((inbuffer[7]>>12)&0xf);
287
  *(ptr++)=(inbuffer[7]>>5)&0x7f;
288
  *(ptr++)=((inbuffer[7]<<2)&0x7c)|((inbuffer[8]>>14)&3);
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  *(ptr++)=(inbuffer[8]>>7)&0x7f;
290
  *(ptr++)=((inbuffer[8]<<1)&0xfe)|((inbuffer[9]>>15)&1);
291
  *(ptr++)=(inbuffer[9]>>8)&0x7f;
292
  *(ptr++)=(inbuffer[9]>>1)&0x7f;
293

    
294
  *(output++)=outbuffer[11];
295
  for (x=1;x<11;*(output++)=outbuffer[x++]);
296
  ptr=outbuffer+12;
297
  for (x=0;x<16;x+=4)
298
  {
299
    *(output++)=ptr[x];
300
    *(output++)=ptr[x+2];
301
    *(output++)=ptr[x+3];
302
    *(output++)=ptr[x+1];    
303
  }
304
}
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306
static unsigned int rms(int *data, int f)
307
{
308
  int *c;
309
  int x;
310
  unsigned int res;
311
  int b;
312

    
313
  c=data;
314
  b=0;
315
  res=0x10000;
316
  for (x=0;x<10;x++)
317
  {
318
    res=(((0x1000000-(*c)*(*c))>>12)*res)>>12;
319
    if (res==0) return 0;
320
    if (res<=0x3fff)
321
    {
322
      while (res<=0x3fff)
323
      {
324
        b++;
325
        res<<=2;
326
      }
327
    } else {
328
      if (res>0x10000)
329
        return 0; /* We're screwed, might as well go out with a bang. :P */
330
    }
331
    c++;
332
  }
333
  if (res>0) res=t_sqrt(res);
334

    
335
  res>>=(b+10);
336
  res=(res*f)>>10;
337
  return res;
338
}
339

    
340
static void dec1(Real144_internal *glob, int *data, int *inp, int n, int f)
341
{
342
  short *ptr,*end;
343

    
344
  *(glob->decptr++)=rms(data,f);
345
  glob->decptr++;
346
  end=(ptr=glob->decsp)+(n*10);
347
  while (ptr<end) *(ptr++)=*(inp++);
348
}
349

    
350
static int eq(Real144_internal *glob, short *in, int *target)
351
{
352
  int retval;
353
  int a;
354
  int b;
355
  int c;
356
  unsigned int u;
357
  short *sptr;
358
  int *ptr1,*ptr2,*ptr3;
359
  int *bp1,*bp2,*temp;
360

    
361
  retval=0;
362
  bp1=glob->buffer1;
363
  bp2=glob->buffer2;
364
  ptr2=(ptr3=glob->buffer2)+9;
365
  sptr=in;
366
  while (ptr2>=ptr3)
367
    *(ptr3++)=*(sptr++);
368

    
369
  target+=9;
370
  a=bp2[9];
371
  *target=a;
372
  if (a+0x1000>0x1fff)
373
    return 0; /* We're screwed, might as well go out with a bang. :P */
374
  c=8;u=a;
375
  while (c>=0)
376
  {
377
    if (u==0x1000) u++;
378
    if (u==0xfffff000) u--;
379
    b=0x1000-((u*u)>>12);
380
    if (b==0) b++;
381
    ptr2=bp1;
382
    ptr1=(ptr3=bp2)+c;
383
    for (u=0;u<=c;u++)
384
      *(ptr2++)=((*(ptr3++)-(((*target)*(*(ptr1--)))>>12))*(0x1000000/b))>>12;
385
    *(--target)=u=bp1[(c--)];
386
    if ((u+0x1000)>0x1fff) retval=1;
387
    temp=bp2;
388
    bp2=bp1;
389
    bp1=temp;
390
  }
391
  return retval;
392
}
393

    
394
static void dec2(Real144_internal *glob, int *data, int *inp, int n, int f, int *inp2, int l)
395
{
396
  unsigned int *ptr1,*ptr2;
397
  int work[10];
398
  int a,b;
399
  int x;
400
  int result;
401

    
402
  if(l+1<NBLOCKS/2) a=NBLOCKS-(l+1);
403
  else a=l+1;
404
  b=NBLOCKS-a;
405
  if (l==0)
406
  {
407
    glob->decsp=glob->sptr=glob->gbuf2;
408
    glob->decptr=glob->gbuf1;
409
  }
410
  ptr1=inp;
411
  ptr2=inp2;
412
  for (x=0;x<10*n;x++)
413
    *(glob->sptr++)=(a*(*ptr1++)+b*(*ptr2++))>>2;
414
  result=eq(glob,glob->decsp,work);
415
  if (result==1)
416
  {
417
    dec1(glob,data,inp,n,f);
418
  } else {
419
    *(glob->decptr++)=rms(work,f);
420
    glob->decptr++;
421
  }
422
  glob->decsp+=n*10;
423
}
424

    
425
/* Uncompress one block (20 bytes -> 160*2 bytes) */
426
static int ra144_decode_frame(AVCodecContext * avctx,
427
            void *data, int *data_size,
428
            uint8_t * buf, int buf_size)
429
{
430
  unsigned int a,b,c;
431
  long s;
432
  signed short *shptr;
433
  unsigned int *lptr,*temp;
434
  const short **dptr;
435
  void *datao;
436
  Real144_internal *glob=avctx->priv_data;
437

    
438
  datao = data;
439
  unpack_input(buf,glob->unpacked);
440
  
441
  glob->iptr=glob->unpacked;
442
  glob->val=decodetable[0][(*(glob->iptr++))<<1];
443

    
444
  dptr=decodetable+1;
445
  lptr=glob->swapbuf1;
446
  while (lptr<glob->swapbuf1+10)
447
    *(lptr++)=(*(dptr++))[(*(glob->iptr++))<<1];
448

    
449
  do_voice(glob->swapbuf1,glob->swapbuf2);
450

    
451
  a=t_sqrt(glob->val*glob->oldval)>>12;
452

    
453
  for (c=0;c<NBLOCKS;c++) {
454
    if (c==(NBLOCKS-1)) {
455
      dec1(glob,glob->swapbuf1,glob->swapbuf2,3,glob->val);
456
    } else {
457
      if (c*2==(NBLOCKS-2)) {
458
        if (glob->oldval<glob->val) {
459
          dec2(glob,glob->swapbuf1,glob->swapbuf2,3,a,glob->swapbuf2alt,c);
460
        } else {
461
          dec2(glob,glob->swapbuf1alt,glob->swapbuf2alt,3,a,glob->swapbuf2,c);
462
        }
463
      } else {
464
        if (c*2<(NBLOCKS-2)) {
465
          dec2(glob,glob->swapbuf1alt,glob->swapbuf2alt,3,glob->oldval,glob->swapbuf2,c);
466
        } else {
467
          dec2(glob,glob->swapbuf1,glob->swapbuf2,3,glob->val,glob->swapbuf2alt,c);
468
        }
469
      }
470
    }
471
  }
472

    
473
  /* do output */
474
  for (b=0,c=0;c<4;c++) {
475
    glob->gval=glob->gbuf1[c*2];
476
    glob->gsp=glob->gbuf2+b;
477
    do_output_subblock(glob,glob->resetflag);
478
    glob->resetflag=0;
479

    
480
    shptr=glob->output_buffer;
481
    while (shptr<glob->output_buffer+BLOCKSIZE) {
482
      s=*(shptr++)<<2;
483
      *((int16_t *)data)=s;
484
      if (s>32767) *((int16_t *)data)=32767;
485
      if (s<-32767) *((int16_t *)data)=-32768;
486
      ((int16_t *)data)++;
487
    }
488
    b+=30;
489
  }
490

    
491
  glob->oldval=glob->val;
492
  temp=glob->swapbuf1alt;
493
  glob->swapbuf1alt=glob->swapbuf1;
494
  glob->swapbuf1=temp;
495
  temp=glob->swapbuf2alt;
496
  glob->swapbuf2alt=glob->swapbuf2;
497
  glob->swapbuf2=temp;
498
  *data_size=data-datao;
499
  return 20;
500
}
501

    
502

    
503
AVCodec ra_144_decoder =
504
{
505
    "real_144",
506
    CODEC_TYPE_AUDIO,
507
    CODEC_ID_RA_144,
508
    sizeof(Real144_internal),
509
    ra144_decode_init,
510
    NULL,
511
    NULL,
512
    ra144_decode_frame,
513
};