depuncturing.c

来自「This model is just testing an idea of MI」· C语言 代码 · 共 66 行

/*****************************************************************************/
/*   FIle Name : depuncturing.c                                              */
/*   Description : WLAN FEC depuncturing for Decoder                         */
/*                 Rate 0:1/2 1:2/3 2:3/4                                    */
/*   author : miffie                                                         */
/*   Date   : aug/04/05                                                      */
/*   Copyright (c) 2005 miffie   All rights reserved.                          */
/*****************************************************************************/
struct binaryset depuncturing (struct binaryset datain, char rate) {
int 	ii ;
int 	size_p ; //size for punctured
char 	shifter ;
char 	tmp1, tmp2 ;
char	*p , *q;
char    UNKNW = 8 ; //unknown data for punctured bit
struct binaryset bset0 ;

  //Main 
    if ((q = (char *)malloc(2*datain.size*sizeof(char)) ) == NULL) {
        PRINTF( " malloc failed in depuncturing.c\n") ;
    } //fail
    else { //allocated
       PRINTF("depuncturing size=%x rate=%x\n" , datain.size, rate ) ;
       bset0.format = 1 ; // byte
       bset0.size = datain.size ; //
       bset0.data = q ; //

       /////////////////////////////////////////
       //puncturing   Rate 0:1/2 1:2/3 2:3/4
       /////////////////////////////////////////
       p = datain.data ;
       q=bset0.data ;
       size_p=0 ;
       switch ( rate ) {//switch
         case 1: { //2/3
                   for (ii=0;ii<bset0.size;ii++) { //for
                     *q++ = *p++ ; size_p ++ ;
                     if ((ii%3)==2) { *q++ = UNKNW ; size_p++ ; }
                   } //for
                   break ;
                 } //2/3
         case 2: { //3/4
                   for (ii=0;ii<bset0.size;ii++) { //for
                     *q++ = *p++ ; size_p ++ ;
                     if ((ii%4)==2) { 
                        *q++ = UNKNW ; size_p++ ; 
                        *q++ = UNKNW ; size_p++ ; 
                     }
                   } //for
                   break ;
                 } //3/4
         default : { //1/2
                   size_p = bset0.size ;
                   for (ii=0;ii<bset0.size;ii++) { //for
                     *q++ = *p++ ; 
                   } //for
                   break ;
                 } //1/2
       }//switch
       bset0.size = size_p ; //

    } //allocated
    free ( datain.data ) ;
    return ( bset0 ) ;
} //depuncturing