mpegimdc.c

uclinux下s3c4510B CPU播放mp3 C程序

   prev[ 8 ] = W( temp, 26 );   prev[ 9 ] = W( temp, 27 );

   return 0;

#undef O
#undef set_k
#undef S
#undef W
#undef MT
#undef M

}

static int imdct_s( IMDCT_IO_TYPE *x, IMDCT_IO_TYPE *out,
                    MPEGIMDCT_BLOCK_TYPE *prev, WIN_TYPE *win )
{
   static const IMDCT_TYPE K0 = 0.9914448614 * (1<<IMDCT_BITS); /* #3 Added const */
   static const IMDCT_TYPE K1 = 0.9238795325 * (1<<IMDCT_BITS); /* #3 Added const */
   static const IMDCT_TYPE K2 = 0.7933533403 * (1<<IMDCT_BITS); /* #3 Added const */
   static const IMDCT_TYPE K3 = 0.6087614290 * (1<<IMDCT_BITS); /* #3 Added const */
   static const IMDCT_TYPE K4 = 0.3826834324 * (1<<IMDCT_BITS); /* #3 Added const */
   static const IMDCT_TYPE K5 = 0.1305261922 * (1<<IMDCT_BITS); /* #3 Added const */

   IMDCT_TYPE s[ 2 ];
   IMDCT_TYPE t[ 2 ];
   IMDCT_TYPE temp;
   INT16 i;
#ifdef IMDCT_INT
#define M( xi, Kx ) ((INT32)x[ (xi*3) ] * (Kx))
#define MT( ti, Kx ) (t[ ti ] * (Kx))
#define W( t, wi ) WIN_MULT( (t>>IMDCT_BITS), win[ wi ] )
#else
#define M( xi, Kx ) (REAL)(x[ (xi*3) ] * (Kx))
#define MT( ti, Kx ) (REAL)(t[ ti ] * (Kx))
#define W( t, wi ) (REAL)(t * win[ wi ])
#endif
#define O( i ) out[ i*32 ]

// Step 1
   O( 0 ) = prev[ 0 ]; O( 1 ) = prev[ 1 ]; O( 2 ) = prev[ 2 ];
   O( 3 ) = prev[ 3 ]; O( 4 ) = prev[ 4 ]; O( 5 ) = prev[ 5 ];

   s[ 0 ] = M( 1, K1 ) + M( 4, K4 );
   s[ 1 ] = M( 1, K4 ) - M( 4, K1 );

   t[ 0 ] =  x[0*3] - x[3*3];
   t[ 1 ] =  x[2*3] + x[5*3];
   // 0
   temp =   M( 0, K3 ) - M( 2, K5 ) + M( 3, K0 ) - M( 5, K2 ) - s[ 0 ];
   O( 6 ) = prev[ 6 ] + W( temp, 0 );   O( 11 ) = prev[ 11 ] -W( temp, 5 );
   // 1
   temp =   MT( 0, K4 ) + MT( 1, K1 ) - s[ 0 ];
   O( 7 ) = prev[ 7 ] + W( temp, 1 );   O( 10 ) = prev[ 10 ] -W( temp, 4 );
   // 2
   temp =   M( 0, K5 ) + M( 2, K3 ) - M( 3, K2 ) - M( 5, K0 ) - s[ 1 ];
   O( 8 ) = prev[ 8 ] + W( temp, 2 );   O( 9 ) = prev[ 9 ] -W( temp, 3 );
   // 3

   // 3+3
   temp = - M( 0, K2 ) + M( 2, K0 ) + M( 3, K5 ) - M( 5, K3 ) + s[ 1 ];
   O( 12 ) = W( temp, 6 );   O( 17 ) = W( temp, 11 );
   // 4+3
   temp = - MT( 0, K1 ) + MT( 1, K4 ) - s[ 1 ];
   O( 13 ) = W( temp, 7 );   O( 16 ) = W( temp, 10 );
   // 5+3
   temp = - M( 0, K0 ) - M( 2, K2 ) - M( 3, K3 ) - M( 5, K5 ) - s[ 0 ];
   O( 14 ) = W( temp, 8 );   O( 15 ) = W( temp, 9 );

// Step 2
   x++;

   s[ 0 ] = M( 1, K1 ) + M( 4, K4 );
   s[ 1 ] = M( 1, K4 ) - M( 4, K1 );

   t[ 0 ] =  x[0*3] - x[3*3];
   t[ 1 ] =  x[2*3] + x[5*3];
   // 0
   temp =   M( 0, K3 ) - M( 2, K5 ) + M( 3, K0 ) - M( 5, K2 ) - s[ 0 ];
   O( 12 ) += W( temp, 0 );   O( 17 ) += -W( temp, 5 );
   // 1
   temp =   MT( 0, K4 ) + MT( 1, K1 ) - s[ 0 ];
   O( 13 ) += W( temp, 1 );   O( 16 ) += -W( temp, 4 );
   // 2
   temp =   M( 0, K5 ) + M( 2, K3 ) - M( 3, K2 ) - M( 5, K0 ) - s[ 1 ];
   O( 14 ) += W( temp, 2 );   O( 15 ) += -W( temp, 3 );
   // 3

   // 3+3
   temp = - M( 0, K2 ) + M( 2, K0 ) + M( 3, K5 ) - M( 5, K3 ) + s[ 1 ];
   prev[ 0 ] = W( temp, 6 );   prev[ 5 ] = W( temp, 11 );
   // 4+3
   temp = - MT( 0, K1 ) + MT( 1, K4 ) - s[ 1 ];
   prev[ 1 ] = W( temp, 7 );   prev[ 4 ] = W( temp, 10 );
   // 5+3
   temp = - M( 0, K0 ) - M( 2, K2 ) - M( 3, K3 ) - M( 5, K5 ) - s[ 0 ];
   prev[ 2 ] = W( temp, 8 );   prev[ 3 ] = W( temp, 9 );

// Step 3
   x++;

   s[ 0 ] = M( 1, K1 ) + M( 4, K4 );
   s[ 1 ] = M( 1, K4 ) - M( 4, K1 );

   t[ 0 ] =  x[0*3] - x[3*3];
   t[ 1 ] =  x[2*3] + x[5*3];
   // 0
   temp =   M( 0, K3 ) - M( 2, K5 ) + M( 3, K0 ) - M( 5, K2 ) - s[ 0 ];
   prev[ 0 ] += W( temp, 0 );   prev[ 5 ] += -W( temp, 5 );
   // 1
   temp =   MT( 0, K4 ) + MT( 1, K1 ) - s[ 0 ];
   prev[ 1 ] += W( temp, 1 );   prev[ 4 ] += -W( temp, 4 );
   // 2
   temp =   M( 0, K5 ) + M( 2, K3 ) - M( 3, K2 ) - M( 5, K0 ) - s[ 1 ];
   prev[ 2 ] += W( temp, 2 );   prev[ 3 ] += -W( temp, 3 );
   // 3

   // 3+3
   temp = - M( 0, K2 ) + M( 2, K0 ) + M( 3, K5 ) - M( 5, K3 ) + s[ 1 ];
   prev[ 6 ] = W( temp, 6 );   prev[ 11 ] = W( temp, 11 );
   // 4+3
   temp = - MT( 0, K1 ) + MT( 1, K4 ) - s[ 1 ];
   prev[ 7 ] = W( temp, 7 );   prev[ 10 ] = W( temp, 10 );
   // 5+3
   temp = - M( 0, K0 ) - M( 2, K2 ) - M( 3, K3 ) - M( 5, K5 ) - s[ 0 ];
   prev[ 8 ] = W( temp, 8 );   prev[ 9 ] = W( temp, 9 );

   prev[ 12 ] = prev[ 13 ] = prev[ 14 ] =
   prev[ 15 ] = prev[ 16 ] = prev[ 17 ] = 0;

   return 0;

#undef O
#undef set_k
#undef W
#undef MT
#undef M
}


int MPEGIMDCT_hybrid( MPEGIMDCT *mpegimdct, MPEGAUD_FRACT_TYPE *in,
                      MPEGAUD_FRACT_TYPE *out, INT16 block_type, BOOL mixed,
                      INT16 ch, INT16 sb_max )
/*--------------------------------------------------------------------------
   Apply the hybrid imdct to a granule
   Return 0 if Ok
*/
{
#ifndef USE_IMDCT_TABLE
   static WIN_TYPE win[ 2 ][ 4 ][ 36 ];
#endif
   static BOOL init = FALSE;
   register MPEGIMDCT_BLOCK_TYPE *prev;
   INT16 sb;
   INT16 bt;
#ifdef IMDCT_TABLE_GEN
   static FILE *fdct_out;
   int i, j;
#endif

   if( !init ) {
      INT16 i, j;

#ifdef IMDCT_INT
#if !defined(USE_IMDCT_TABLE) || defined(IMDCT_TABLE_GEN)
      printf("Generating table values\n");
      // Block type 0
      for( i=0; i<36; i++ ) win[0][0][i] = sin( PI/36 * (i+0.5) ) * (1<<WIN_BITS);

      // Block type 1
      for( i=0;  i<18; i++ ) win[0][1][i] = sin( PI/36 * (i+0.5) ) * (1<<WIN_BITS);
      for( i=18; i<24; i++ ) win[0][1][i] = 1<<WIN_BITS;
      for( i=24; i<30; i++ ) win[0][1][i] = sin( PI/12 * (i+0.5-18) ) * (1<<WIN_BITS);
      for( i=30; i<36; i++ ) win[0][1][i] = 0;

      // Block type 3
      for( i=0;  i<6;  i++ ) win[0][3][i] = 0.0;
      for( i=6;  i<12; i++ ) win[0][3][i] = sin( PI/12 * (i+0.5-6) ) * (1<<WIN_BITS);
      for( i=12; i<18; i++ ) win[0][3][i] = 1<<WIN_BITS;
      for( i=18; i<36; i++ ) win[0][3][i] = sin( PI/36 * (i+0.5) ) * (1<<WIN_BITS);

      // Block type 2
      for( i=0;  i<12; i++) win[0][2][i] = sin( PI/12 * (i+0.5) ) * (1<<WIN_BITS);
      for( i=12; i<36; i++) win[0][2][i] = 0;

      for(j=0; j<4; j++) {
         for(i=0;i<36;i+=2) win[1][j][i] = +win[0][j][i];
         for(i=1;i<36;i+=2) win[1][j][i] = -win[0][j][i];
      }
#endif //if ~defined(USE_IMDCT_TABLE) || defined(IMDCT_TABLE_GEN)
#else 
      // Block type 0
      for( i=0; i<36; i++ ) win[0][0][i] = sin( PI/36 * (i+0.5) );

      // Block type 1
      for( i=0;  i<18; i++ ) win[0][1][i] = sin( PI/36 * (i+0.5) );
      for( i=18; i<24; i++ ) win[0][1][i] = 1.0;
      for( i=24; i<30; i++ ) win[0][1][i] = sin( PI/12 * (i+0.5-18) );
      for( i=30; i<36; i++ ) win[0][1][i] = 0.0;

      // Block type 3
      for( i=0;  i<6;  i++ ) win[0][3][i] = 0.0;
      for( i=6;  i<12; i++ ) win[0][3][i] = sin( PI/12 * (i+0.5-6) );
      for( i=12; i<18; i++ ) win[0][3][i] = 1.0;
      for( i=18; i<36; i++ ) win[0][3][i] = sin( PI/36 * (i+0.5) );

      // Block type 2
      for( i=0;  i<12; i++) win[0][2][i] = sin( PI/12 * (i+0.5) ) ;
      for( i=12; i<36; i++) win[0][2][i] = 0.0;

      for(j=0; j<4; j++) {
         for(i=0;i<36;i+=2) win[1][j][i] = +win[0][j][i];
         for(i=1;i<36;i+=2) win[1][j][i] = -win[0][j][i];
      }
#endif //#if IMDCT_INT
#ifdef IMDCT_TABLE_GEN

      fdct_out = fopen("imdct.out", "w");
      fprintf(fdct_out,"static short win[2][4][36] =\n{\n");
      fprintf(fdct_out,"  /* Start of table */\n  {\n", j);
      for(j=0; j<4; j++) {
	fprintf(fdct_out,"   /* Start of row %d */\n    {\n", j);
	for(i=0; i < 32; i = i + 4) {
	  fprintf(fdct_out,"      %d, %d, %d, %d, \n",
		win[0][j][i], win[0][j][i+1], win[0][j][i+2], win[0][j][i+3]);
	}
	// finish row, no comma at end
	fprintf(fdct_out,"      %d, %d, %d, %d \n",
		win[0][j][i], win[0][j][i+1], win[0][j][i+2], win[0][j][i+3]);
	fprintf(fdct_out,"    }, /* end of row %d */\n", j);
      }
      fprintf(fdct_out,"  },\n /* Start of second half of table */\n  {\n", j);
      for(j=0; j<4; j++) {
	fprintf(fdct_out,"    /* Start of row %d */\n    {\n", j);
	for(i=0; i < 32; i = i + 4) {
	  fprintf(fdct_out,"      %d, %d, %d, %d, \n",
		win[1][j][i], win[1][j][i+1], win[1][j][i+2], win[1][j][i+3]);
	}
	// finish row, no comma at end
	fprintf(fdct_out,"      %d, %d, %d, %d \n",
		win[1][j][i], win[1][j][i+1], win[1][j][i+2], win[1][j][i+3]);
	fprintf(fdct_out,"    }, /* end of row %d */\n", j);
      }
      fprintf(fdct_out,"  }\n/* End of second half of table */\n};\n", j);

      fclose(fdct_out);
#endif
      init = TRUE;
   }

#define O( i ) out[ i*32 ]

   prev = mpegimdct->prevblk[ ch ];
   for( sb=0; sb<sb_max; sb++ ) {
      bt = ((mixed) && (sb < 2)) ? 0 : block_type;

      if( bt == 2 ) { // Short block
         imdct_s( in, out, prev, &win[ sb & 1 ][ bt ][ 0 ] );
      }
      else {
         imdct_l( in, out, prev, &win[ sb & 1 ][ bt ][ 0 ] );
      }

      in += 18;
      out++;
      prev += 18;
   }

   for( ; sb<MPA_SBLIMIT; sb++ ) {
      // overlap addition with 0
      O( 0 ) = *prev; *prev++ = 0; O( 1 ) = *prev; *prev++ = 0; O( 2 ) = *prev; *prev++ = 0;
      O( 3 ) = *prev; *prev++ = 0; O( 4 ) = *prev; *prev++ = 0; O( 5 ) = *prev; *prev++ = 0;
      O( 6 ) = *prev; *prev++ = 0; O( 7 ) = *prev; *prev++ = 0; O( 8 ) = *prev; *prev++ = 0;
      O( 9 ) = *prev; *prev++ = 0; O( 10 ) = *prev; *prev++ = 0; O( 11 ) = *prev; *prev++ = 0;
      O( 12 ) = *prev; *prev++ = 0; O( 13 ) = *prev; *prev++ = 0; O( 14 ) = *prev; *prev++ = 0;
      O( 15 ) = *prev; *prev++ = 0; O( 16 ) = *prev; *prev++ = 0; O( 17 ) = *prev; *prev++ = 0;
      out++;
   }

MPEGAUD_CHECK_DEMO;

   return 0;

} /* MPEGIMDCT_hybrid */

#endif // NOT NEW_IMDCT

#endif // NOT ASM_OPTIMIZE

int MPEGIMDCT_reset( MPEGIMDCT *mpegimdct )
/*-----------------------------------------
   Reset the MPEGIMDCT module
*/
{
   if( !mpegimdct ) return -1;
   // Reset previous block buffer
   memset( mpegimdct->prevblk, 0, MPA_MAX_CHANNELS * MPA_GRANULE_SIZE * sizeof( MPEGIMDCT_BLOCK_TYPE ) );

   return 0;

} /* MPEGIMDCT_reset */


void MPEGIMDCT_close( MPEGIMDCT *mpegimdct )
/*------------------------------------------
   Close the MPEGIMDCT module
*/
{
   if( !mpegimdct ) return;
   free( mpegimdct );

} /* MPEGIMDCT_close */

MPEGIMDCT *MPEGIMDCT_open( void )
/*-------------------------------
   Open the MPEGIMDCT module
*/
{
   MPEGIMDCT *mpegimdct;

   mpegimdct = (MPEGIMDCT *)malloc( sizeof(MPEGIMDCT) );
   if( !mpegimdct ) return NULL;
   (void)MPEGIMDCT_reset( mpegimdct );

   return mpegimdct;

} /* MPEGIMDCT_open */