interleave.h

00001     void interleave( unsigned char *input, unsigned char *output ){
00002     
00003     unsigned int outState = 0;
00004     unsigned int outByte = 0;
00005     
00006     for( unsigned int i = 0 ; i < 36 ; ++i ){
00007         for(unsigned int j = 0 ; j < 30 ; ++j){
00008             unsigned int x = j*36+i;
00009             unsigned char tempBit = ((input[x >> 3]) >> (7-(x % 8))) & 1;
00010             switch(outState){
00011                 case 0:
00012                     outState = 1;
00013                     output[outByte] = tempBit << 7;
00014                     break;
00015                 case 1:
00016                     outState = 2;
00017                     output[outByte] += tempBit << 6;
00018                     break;
00019                 case 2:
00020                     outState = 3;
00021                     output[outByte] += tempBit << 5;
00022                     break;
00023                 case 3:
00024                     outState = 4;
00025                     output[outByte] += tempBit << 4;
00026                     break;
00027                 case 4:
00028                     outState = 5;
00029                     output[outByte] += tempBit << 3;
00030                     break;
00031                 case 5:
00032                     outState = 6;
00033                     output[outByte] += tempBit << 2;
00034                     break;
00035                 case 6:
00036                     outState = 7;
00037                     output[outByte] += tempBit << 1;
00038                     break;
00039                 case 7:
00040                     outState = 0;
00041                     output[outByte] += tempBit;
00042                     ++outByte;
00043                     break;
00044             }
00045         }
00046         for(unsigned int j = 0 ; j < 2 ; ++j){
00047             switch(outState){
00048                 case 0:
00049                     output[outByte] = 0;
00050                     outState = 1;
00051                     break;
00052                 case 1:
00053                     outState = 2;
00054                     break;
00055                 case 2:
00056                     outState = 3;
00057                     break;
00058                 case 3:
00059                     outState = 4;
00060                     break;
00061                 case 4:
00062                     outState = 5;
00063                     break;
00064                 case 5:
00065                     outState = 6;
00066                     break;
00067                 case 6:
00068                     outState = 7;
00069                     break;
00070                 case 7:
00071                     outState = 0;
00072                     ++outByte;
00073                     break;
00074             }
00075         }
00076     }
00077 }