gsm_enco.c

IP网络语音通讯软件源代码. 不可多得的语音源代码

/*
 * 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: n:\\development/speak_freely/GSM/GSM_ENCO.C,v 1.1.1.1 1998/10/15 00:47:39 Administrator Exp $ */

#include "private.h"
#include "gsm.h"
#include "proto.h"

void gsm_encode P3((s, source, c), gsm s, gsm_signal * source, gsm_byte * c)
{
		word			LARc[8], Nc[4], Mc[4], bc[4], xmaxc[4], xmc[13*4];

		Gsm_Coder(s, source, LARc, Nc, bc, Mc, xmaxc, xmc);


		/*		variable		size

				GSM_MAGIC		4

				LARc[0] 		6
				LARc[1] 		6
				LARc[2] 		5
				LARc[3] 		5
				LARc[4] 		4
				LARc[5] 		4
				LARc[6] 		3
				LARc[7] 		3

				Nc[0]			7
				bc[0]			2
				Mc[0]			2
				xmaxc[0]		6
				xmc[0]			3
				xmc[1]			3
				xmc[2]			3
				xmc[3]			3
				xmc[4]			3
				xmc[5]			3
				xmc[6]			3
				xmc[7]			3
				xmc[8]			3
				xmc[9]			3
				xmc[10] 		3
				xmc[11] 		3
				xmc[12] 		3

				Nc[1]			7
				bc[1]			2
				Mc[1]			2
				xmaxc[1]		6
				xmc[13] 		3
				xmc[14] 		3
				xmc[15] 		3
				xmc[16] 		3
				xmc[17] 		3
				xmc[18] 		3
				xmc[19] 		3
				xmc[20] 		3
				xmc[21] 		3
				xmc[22] 		3
				xmc[23] 		3
				xmc[24] 		3
				xmc[25] 		3

				Nc[2]			7
				bc[2]			2
				Mc[2]			2
				xmaxc[2]		6
				xmc[26] 		3
				xmc[27] 		3
				xmc[28] 		3
				xmc[29] 		3
				xmc[30] 		3
				xmc[31] 		3
				xmc[32] 		3
				xmc[33] 		3
				xmc[34] 		3
				xmc[35] 		3
				xmc[36] 		3
				xmc[37] 		3
				xmc[38] 		3

				Nc[3]			7
				bc[3]			2
				Mc[3]			2
				xmaxc[3]		6
				xmc[39] 		3
				xmc[40] 		3
				xmc[41] 		3
				xmc[42] 		3
				xmc[43] 		3
				xmc[44] 		3
				xmc[45] 		3
				xmc[46] 		3
				xmc[47] 		3
				xmc[48] 		3
				xmc[49] 		3
				xmc[50] 		3
				xmc[51] 		3
		*/


		*c++ =	 ((GSM_MAGIC & 0xF) << 4)				/* 1 */
			   | ((LARc[0] >> 2) & 0xF);
		*c++ =	 ((LARc[0] & 0x3) << 6)
			   | (LARc[1] & 0x3F);
		*c++ =	 ((LARc[2] & 0x1F) << 3)
			   | ((LARc[3] >> 2) & 0x7);
		*c++ =	 ((LARc[3] & 0x3) << 6)
			   | ((LARc[4] & 0xF) << 2)
			   | ((LARc[5] >> 2) & 0x3);
		*c++ =	 ((LARc[5] & 0x3) << 6)
			   | ((LARc[6] & 0x7) << 3)
			   | (LARc[7] & 0x7);
		*c++ =	 ((Nc[0] & 0x7F) << 1)
			   | ((bc[0] >> 1) & 0x1);
		*c++ =	 ((bc[0] & 0x1) << 7)
			   | ((Mc[0] & 0x3) << 5)
			   | ((xmaxc[0] >> 1) & 0x1F);
		*c++ =	 ((xmaxc[0] & 0x1) << 7)
			   | ((xmc[0] & 0x7) << 4)
			   | ((xmc[1] & 0x7) << 1)
			   | ((xmc[2] >> 2) & 0x1);
		*c++ =	 ((xmc[2] & 0x3) << 6)
			   | ((xmc[3] & 0x7) << 3)
			   | (xmc[4] & 0x7);
		*c++ =	 ((xmc[5] & 0x7) << 5)					/* 10 */
			   | ((xmc[6] & 0x7) << 2)
			   | ((xmc[7] >> 1) & 0x3);
		*c++ =	 ((xmc[7] & 0x1) << 7)
			   | ((xmc[8] & 0x7) << 4)
			   | ((xmc[9] & 0x7) << 1)
			   | ((xmc[10] >> 2) & 0x1);
		*c++ =	 ((xmc[10] & 0x3) << 6)
			   | ((xmc[11] & 0x7) << 3)
			   | (xmc[12] & 0x7);
		*c++ =	 ((Nc[1] & 0x7F) << 1)
			   | ((bc[1] >> 1) & 0x1);
		*c++ =	 ((bc[1] & 0x1) << 7)
			   | ((Mc[1] & 0x3) << 5)
			   | ((xmaxc[1] >> 1) & 0x1F);
		*c++ =	 ((xmaxc[1] & 0x1) << 7)
			   | ((xmc[13] & 0x7) << 4)
			   | ((xmc[14] & 0x7) << 1)
			   | ((xmc[15] >> 2) & 0x1);
		*c++ =	 ((xmc[15] & 0x3) << 6)
			   | ((xmc[16] & 0x7) << 3)
			   | (xmc[17] & 0x7);
		*c++ =	 ((xmc[18] & 0x7) << 5)
			   | ((xmc[19] & 0x7) << 2)
			   | ((xmc[20] >> 1) & 0x3);
		*c++ =	 ((xmc[20] & 0x1) << 7)
			   | ((xmc[21] & 0x7) << 4)
			   | ((xmc[22] & 0x7) << 1)
			   | ((xmc[23] >> 2) & 0x1);
		*c++ =	 ((xmc[23] & 0x3) << 6)
			   | ((xmc[24] & 0x7) << 3)
			   | (xmc[25] & 0x7);
		*c++ =	 ((Nc[2] & 0x7F) << 1)					/* 20 */
			   | ((bc[2] >> 1) & 0x1);
		*c++ =	 ((bc[2] & 0x1) << 7)
			   | ((Mc[2] & 0x3) << 5)
			   | ((xmaxc[2] >> 1) & 0x1F);
		*c++ =	 ((xmaxc[2] & 0x1) << 7)
			   | ((xmc[26] & 0x7) << 4)
			   | ((xmc[27] & 0x7) << 1)
			   | ((xmc[28] >> 2) & 0x1);
		*c++ =	 ((xmc[28] & 0x3) << 6)
			   | ((xmc[29] & 0x7) << 3)
			   | (xmc[30] & 0x7);
		*c++ =	 ((xmc[31] & 0x7) << 5)
			   | ((xmc[32] & 0x7) << 2)
			   | ((xmc[33] >> 1) & 0x3);
		*c++ =	 ((xmc[33] & 0x1) << 7)
			   | ((xmc[34] & 0x7) << 4)
			   | ((xmc[35] & 0x7) << 1)
			   | ((xmc[36] >> 2) & 0x1);
		*c++ =	 ((xmc[36] & 0x3) << 6)
			   | ((xmc[37] & 0x7) << 3)
			   | (xmc[38] & 0x7);
		*c++ =	 ((Nc[3] & 0x7F) << 1)
			   | ((bc[3] >> 1) & 0x1);
		*c++ =	 ((bc[3] & 0x1) << 7)
			   | ((Mc[3] & 0x3) << 5)
			   | ((xmaxc[3] >> 1) & 0x1F);
		*c++ =	 ((xmaxc[3] & 0x1) << 7)
			   | ((xmc[39] & 0x7) << 4)
			   | ((xmc[40] & 0x7) << 1)
			   | ((xmc[41] >> 2) & 0x1);
		*c++ =	 ((xmc[41] & 0x3) << 6) 				/* 30 */
			   | ((xmc[42] & 0x7) << 3)
			   | (xmc[43] & 0x7);
		*c++ =	 ((xmc[44] & 0x7) << 5)
			   | ((xmc[45] & 0x7) << 2)
			   | ((xmc[46] >> 1) & 0x3);
		*c++ =	 ((xmc[46] & 0x1) << 7)
			   | ((xmc[47] & 0x7) << 4)
			   | ((xmc[48] & 0x7) << 1)
			   | ((xmc[49] >> 2) & 0x1);
		*c++ =	 ((xmc[49] & 0x3) << 6)
			   | ((xmc[50] & 0x7) << 3)
			   | (xmc[51] & 0x7);
}