mp3lib/dct12.c

   1 /*
   2  * new DCT12
   3  */
   4 static void dct12(real *in,real *rawout1,real *rawout2,register real *wi,register real *ts)
   5 {
   6 #define DCT12_PART1 \
   7              in5 = in[5*3];  \
   8      in5 += (in4 = in[4*3]); \
   9      in4 += (in3 = in[3*3]); \
  10      in3 += (in2 = in[2*3]); \
  11      in2 += (in1 = in[1*3]); \
  12      in1 += (in0 = in[0*3]); \
  13                              \
  14      in5 += in3; in3 += in1; \
  15                              \
  16      in2 *= COS6_1; \
  17      in3 *= COS6_1; \
  18
  19 #define DCT12_PART2 \
  20      in0 += in4 * COS6_2; \
  21                           \
  22      in4 = in0 + in2;     \
  23      in0 -= in2;          \
  24                           \
  25      in1 += in5 * COS6_2; \
  26                           \
  27      in5 = (in1 + in3) * tfcos12[0]; \
  28      in1 = (in1 - in3) * tfcos12[2]; \
  29                          \
  30      in3 = in4 + in5;    \
  31      in4 -= in5;         \
  32                          \
  33      in2 = in0 + in1;    \
  34      in0 -= in1;
  35
  36
  37    {
  38      real in0,in1,in2,in3,in4,in5;
  39      register real *out1 = rawout1;
  40      ts[SBLIMIT*0] = out1[0]; ts[SBLIMIT*1] = out1[1]; ts[SBLIMIT*2] = out1[2];
  41      ts[SBLIMIT*3] = out1[3]; ts[SBLIMIT*4] = out1[4]; ts[SBLIMIT*5] = out1[5];
  42
  43      DCT12_PART1
  44
  45      {
  46        real tmp0,tmp1 = (in0 - in4);
  47        {
  48          real tmp2 = (in1 - in5) * tfcos12[1];
  49          tmp0 = tmp1 + tmp2;
  50          tmp1 -= tmp2;
  51        }
  52        ts[(17-1)*SBLIMIT] = out1[17-1] + tmp0 * wi[11-1];
  53        ts[(12+1)*SBLIMIT] = out1[12+1] + tmp0 * wi[6+1];
  54        ts[(6 +1)*SBLIMIT] = out1[6 +1] + tmp1 * wi[1];
  55        ts[(11-1)*SBLIMIT] = out1[11-1] + tmp1 * wi[5-1];
  56      }
  57
  58      DCT12_PART2
  59
  60      ts[(17-0)*SBLIMIT] = out1[17-0] + in2 * wi[11-0];
  61      ts[(12+0)*SBLIMIT] = out1[12+0] + in2 * wi[6+0];
  62      ts[(12+2)*SBLIMIT] = out1[12+2] + in3 * wi[6+2];
  63      ts[(17-2)*SBLIMIT] = out1[17-2] + in3 * wi[11-2];
  64
  65      ts[(6+0)*SBLIMIT]  = out1[6+0] + in0 * wi[0];
  66      ts[(11-0)*SBLIMIT] = out1[11-0] + in0 * wi[5-0];
  67      ts[(6+2)*SBLIMIT]  = out1[6+2] + in4 * wi[2];
  68      ts[(11-2)*SBLIMIT] = out1[11-2] + in4 * wi[5-2];
  69   }
  70
  71   in++;
  72
  73   {
  74      real in0,in1,in2,in3,in4,in5;
  75      register real *out2 = rawout2;
  76
  77      DCT12_PART1
  78
  79      {
  80        real tmp0,tmp1 = (in0 - in4);
  81        {
  82          real tmp2 = (in1 - in5) * tfcos12[1];
  83          tmp0 = tmp1 + tmp2;
  84          tmp1 -= tmp2;
  85        }
  86        out2[5-1] = tmp0 * wi[11-1];
  87        out2[0+1] = tmp0 * wi[6+1];
  88        ts[(12+1)*SBLIMIT] += tmp1 * wi[1];
  89        ts[(17-1)*SBLIMIT] += tmp1 * wi[5-1];
  90      }
  91
  92      DCT12_PART2
  93
  94      out2[5-0] = in2 * wi[11-0];
  95      out2[0+0] = in2 * wi[6+0];
  96      out2[0+2] = in3 * wi[6+2];
  97      out2[5-2] = in3 * wi[11-2];
  98
  99      ts[(12+0)*SBLIMIT] += in0 * wi[0];
 100      ts[(17-0)*SBLIMIT] += in0 * wi[5-0];
 101      ts[(12+2)*SBLIMIT] += in4 * wi[2];
 102      ts[(17-2)*SBLIMIT] += in4 * wi[5-2];
 103   }
 104
 105   in++;
 106
 107   {
 108      real in0,in1,in2,in3,in4,in5;
 109      register real *out2 = rawout2;
 110      out2[12]=out2[13]=out2[14]=out2[15]=out2[16]=out2[17]=0.0;
 111
 112      DCT12_PART1
 113
 114      {
 115        real tmp0,tmp1 = (in0 - in4);
 116        {
 117          real tmp2 = (in1 - in5) * tfcos12[1];
 118          tmp0 = tmp1 + tmp2;
 119          tmp1 -= tmp2;
 120        }
 121        out2[11-1] = tmp0 * wi[11-1];
 122        out2[6 +1] = tmp0 * wi[6+1];
 123        out2[0+1] += tmp1 * wi[1];
 124        out2[5-1] += tmp1 * wi[5-1];
 125      }
 126
 127      DCT12_PART2
 128
 129      out2[11-0] = in2 * wi[11-0];
 130      out2[6 +0] = in2 * wi[6+0];
 131      out2[6 +2] = in3 * wi[6+2];
 132      out2[11-2] = in3 * wi[11-2];
 133
 134      out2[0+0] += in0 * wi[0];
 135      out2[5-0] += in0 * wi[5-0];
 136      out2[0+2] += in4 * wi[2];
 137      out2[5-2] += in4 * wi[5-2];
 138   }
 139 }