www.pudn.com > speakfs72.zip > GSM_DECO.C, change:2002-01-05,size:3774b


/* 
 * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische 
 * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for 
 * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE. 
 */ 
 
/* $Header: /home/cvsroot/speakfreely/GSM/GSM_DECO.C,v 1.1.1.1 2002/01/05 02:21:05 bcw Exp $ */ 
 
#include "private.h" 
 
#include "gsm.h" 
#include "proto.h" 
 
int gsm_decode P3((s, c, target), gsm s, gsm_byte * c, gsm_signal * target) 
{ 
		word	LARc[8], Nc[4], Mc[4], bc[4], xmaxc[4], xmc[13*4]; 
 
		/* GSM_MAGIC  = (*c >> 4) & 0xF; */ 
 
		if (((*c >> 4) & 0x0F) != GSM_MAGIC) return -1; 
 
		LARc[0]  = (*c++ & 0xF) << 2;			/* 1 */ 
		LARc[0] |= (*c >> 6) & 0x3; 
		LARc[1]  = *c++ & 0x3F; 
		LARc[2]  = (*c >> 3) & 0x1F; 
		LARc[3]  = (*c++ & 0x7) << 2; 
		LARc[3] |= (*c >> 6) & 0x3; 
		LARc[4]  = (*c >> 2) & 0xF; 
		LARc[5]  = (*c++ & 0x3) << 2; 
		LARc[5] |= (*c >> 6) & 0x3; 
		LARc[6]  = (*c >> 3) & 0x7; 
		LARc[7]  = *c++ & 0x7; 
		Nc[0]  = (*c >> 1) & 0x7F; 
		bc[0]  = (*c++ & 0x1) << 1; 
		bc[0] |= (*c >> 7) & 0x1; 
		Mc[0]  = (*c >> 5) & 0x3; 
		xmaxc[0]  = (*c++ & 0x1F) << 1; 
		xmaxc[0] |= (*c >> 7) & 0x1; 
		xmc[0]	= (*c >> 4) & 0x7; 
		xmc[1]	= (*c >> 1) & 0x7; 
		xmc[2]	= (*c++ & 0x1) << 2; 
		xmc[2] |= (*c >> 6) & 0x3; 
		xmc[3]	= (*c >> 3) & 0x7; 
		xmc[4]	= *c++ & 0x7; 
		xmc[5]	= (*c >> 5) & 0x7; 
		xmc[6]	= (*c >> 2) & 0x7; 
		xmc[7]	= (*c++ & 0x3) << 1;			/* 10 */ 
		xmc[7] |= (*c >> 7) & 0x1; 
		xmc[8]	= (*c >> 4) & 0x7; 
		xmc[9]	= (*c >> 1) & 0x7; 
		xmc[10]  = (*c++ & 0x1) << 2; 
		xmc[10] |= (*c >> 6) & 0x3; 
		xmc[11]  = (*c >> 3) & 0x7; 
		xmc[12]  = *c++ & 0x7; 
		Nc[1]  = (*c >> 1) & 0x7F; 
		bc[1]  = (*c++ & 0x1) << 1; 
		bc[1] |= (*c >> 7) & 0x1; 
		Mc[1]  = (*c >> 5) & 0x3; 
		xmaxc[1]  = (*c++ & 0x1F) << 1; 
		xmaxc[1] |= (*c >> 7) & 0x1; 
		xmc[13]  = (*c >> 4) & 0x7; 
		xmc[14]  = (*c >> 1) & 0x7; 
		xmc[15]  = (*c++ & 0x1) << 2; 
		xmc[15] |= (*c >> 6) & 0x3; 
		xmc[16]  = (*c >> 3) & 0x7; 
		xmc[17]  = *c++ & 0x7; 
		xmc[18]  = (*c >> 5) & 0x7; 
		xmc[19]  = (*c >> 2) & 0x7; 
		xmc[20]  = (*c++ & 0x3) << 1; 
		xmc[20] |= (*c >> 7) & 0x1; 
		xmc[21]  = (*c >> 4) & 0x7; 
		xmc[22]  = (*c >> 1) & 0x7; 
		xmc[23]  = (*c++ & 0x1) << 2; 
		xmc[23] |= (*c >> 6) & 0x3; 
		xmc[24]  = (*c >> 3) & 0x7; 
		xmc[25]  = *c++ & 0x7; 
		Nc[2]  = (*c >> 1) & 0x7F; 
		bc[2]  = (*c++ & 0x1) << 1; 			/* 20 */ 
		bc[2] |= (*c >> 7) & 0x1; 
		Mc[2]  = (*c >> 5) & 0x3; 
		xmaxc[2]  = (*c++ & 0x1F) << 1; 
		xmaxc[2] |= (*c >> 7) & 0x1; 
		xmc[26]  = (*c >> 4) & 0x7; 
		xmc[27]  = (*c >> 1) & 0x7; 
		xmc[28]  = (*c++ & 0x1) << 2; 
		xmc[28] |= (*c >> 6) & 0x3; 
		xmc[29]  = (*c >> 3) & 0x7; 
		xmc[30]  = *c++ & 0x7; 
		xmc[31]  = (*c >> 5) & 0x7; 
		xmc[32]  = (*c >> 2) & 0x7; 
		xmc[33]  = (*c++ & 0x3) << 1; 
		xmc[33] |= (*c >> 7) & 0x1; 
		xmc[34]  = (*c >> 4) & 0x7; 
		xmc[35]  = (*c >> 1) & 0x7; 
		xmc[36]  = (*c++ & 0x1) << 2; 
		xmc[36] |= (*c >> 6) & 0x3; 
		xmc[37]  = (*c >> 3) & 0x7; 
		xmc[38]  = *c++ & 0x7; 
		Nc[3]  = (*c >> 1) & 0x7F; 
		bc[3]  = (*c++ & 0x1) << 1; 
		bc[3] |= (*c >> 7) & 0x1; 
		Mc[3]  = (*c >> 5) & 0x3; 
		xmaxc[3]  = (*c++ & 0x1F) << 1; 
		xmaxc[3] |= (*c >> 7) & 0x1; 
		xmc[39]  = (*c >> 4) & 0x7; 
		xmc[40]  = (*c >> 1) & 0x7; 
		xmc[41]  = (*c++ & 0x1) << 2; 
		xmc[41] |= (*c >> 6) & 0x3; 
		xmc[42]  = (*c >> 3) & 0x7; 
		xmc[43]  = *c++ & 0x7;					/* 30  */ 
		xmc[44]  = (*c >> 5) & 0x7; 
		xmc[45]  = (*c >> 2) & 0x7; 
		xmc[46]  = (*c++ & 0x3) << 1; 
		xmc[46] |= (*c >> 7) & 0x1; 
		xmc[47]  = (*c >> 4) & 0x7; 
		xmc[48]  = (*c >> 1) & 0x7; 
		xmc[49]  = (*c++ & 0x1) << 2; 
		xmc[49] |= (*c >> 6) & 0x3; 
		xmc[50]  = (*c >> 3) & 0x7; 
		xmc[51]  = *c & 0x7;					/* 33 */ 
 
		Gsm_Decoder(s, LARc, Nc, bc, Mc, xmaxc, xmc, target); 
 
		return 0; 
}