vit.h

来自「此源码为在ＤＳＰ上实现的卷积纠错编解码算法」· C头文件 代码 · 共 36 行

#include"stdio.h"
//#define NULL ((void *)0)
//#define N1 12*16/*译码后的信息比特数*/
#ifndef VIT
#define VIT
#define	POLYA	0x7 /*生成多项式POLYA和POLYB*/
#define	POLYB	0x5
#define N 254/*输入的待译码的字数，加尾不算在内*/
#define N1 127/*输入的待编码的字数，*/
   /*蝶形运算  */  
#define	BUTTERFLY(j,sym) { \
	long m0,m1;\
	/* ACS for 0 branch */\
	m0 = cmetric[j] + mets[sym];	/* 2*i */\
	m1 = cmetric[j+2] + mets[3^sym];	/* 2*i + 64 */\
	nmetric[2*j] = m0;\
	if(m1 > m0){\
		nmetric[2*j] = m1;\
		dec |= 1 << (2*j) ;\
	}\
	/* ACS for 1 branch */\
	m0 -= (mets[sym] - mets[3^sym]);\
	m1 += (mets[sym] - mets[3^sym]);\
	nmetric[2*j+1] = m0;\
	if(m1 > m0){\
		nmetric[2*j+1] = m1;\
		dec |= 1 << (2*j+1) ;\
	}\
}
#endif


void  vit2en(unsigned int *in,unsigned int *en);
void vitde(unsigned int *en,unsigned int *de);