00001 /* 00002 * Asterisk -- A telephony toolkit for Linux. 00003 * 00004 * A-Law to Signed linear conversion 00005 * 00006 * Copyright (C) 1999, Mark Spencer 00007 * 00008 * Mark Spencer <markster@linux-support.net> 00009 * 00010 * This program is free software, distributed under the terms of 00011 * the GNU General Public License 00012 */ 00013 00014 #ifndef _ASTERISK_ALAW_H 00015 #define _ASTERISK_ALAW_H 00016 00017 //! Init the ulaw conversion stuff 00018 /*! 00019 * To init the ulaw to slinear conversion stuff, this needs to be run. 00020 */ 00021 extern void ast_alaw_init(void); 00022 00023 //! converts signed linear to mulaw 00024 /*! 00025 */ 00026 extern unsigned char __ast_lin2a[8192]; 00027 00028 //! help 00029 extern short __ast_alaw[256]; 00030 00031 #define AST_LIN2A(a) (__ast_lin2a[((unsigned short)(a)) >> 3]) 00032 #define AST_ALAW(a) (__ast_alaw[(a)]) 00033 00034 #endif
1.3.7