/* *  Copyright 2006 by Texas Instruments Incorporated. * *  All rights reserved. Property of Texas Instruments Incorporated. *  Restricted rights to use, duplicate or disclose this code are *  granted through contract. * *//* *  ======== g711_sun.h ======== */#ifndef G711_SUN_INTERNAL_#define G711_SUN_INTERNAL_/* *  ======== linear2alaw ======== * linear2alaw() - Convert a 16-bit linear PCM value to 8-bit A-law * * linear2alaw() accepts an 16-bit integer and encodes it as A-law data. * *              Linear Input Code       Compressed Code *      ------------------------        --------------- *      0000000wxyza                    000wxyz *      0000001wxyza                    001wxyz *      000001wxyzab                    010wxyz *      00001wxyzabc                    011wxyz *      0001wxyzabcd                    100wxyz *      001wxyzabcde                    101wxyz *      01wxyzabcdef                    110wxyz *      1wxyzabcdefg                    111wxyz * * For further information see John C. Bellamy's Digital Telephony, 1982, * John Wiley & Sons, pps 98-111 and 472-476. */extern unsigned char G711_SUN_linear2alaw(short pcm_val); /* 2's complement (16-bit range) *//* *  ======== alaw2linear ======== * alaw2linear() - Convert an A-law value to 16-bit linear PCM * */extern short G711_SUN_alaw2linear(unsigned char a_val);/* *  ======== linear2ulaw ======== * linear2ulaw() - Convert a linear PCM value to u-law * * In order to simplify the encoding process, the original linear magnitude * is biased by adding 33 which shifts the encoding range from (0 - 8158) to * (33 - 8191). The result can be seen in the following encoding table: * *      Biased Linear Input Code        Compressed Code *      ------------------------        --------------- *      00000001wxyza                   000wxyz *      0000001wxyzab                   001wxyz *      000001wxyzabc                   010wxyz *      00001wxyzabcd                   011wxyz *      0001wxyzabcde                   100wxyz *      001wxyzabcdef                   101wxyz *      01wxyzabcdefg                   110wxyz *      1wxyzabcdefgh                   111wxyz * * Each biased linear code has a leading 1 which identifies the segment * number. The value of the segment number is equal to 7 minus the number * of leading 0's. The quantization interval is directly available as the * four bits wxyz.  * The trailing bits (a - h) are ignored. * * Ordinarily the complement of the resulting code word is used for * transmission, and so the code word is complemented before it is returned. * * For further information see John C. Bellamy's Digital Telephony, 1982, * John Wiley & Sons, pps 98-111 and 472-476. */extern unsigned char G711_SUN_linear2ulaw(short pcm_val); /* 2's complement (16-bit range) *//* *  ======== ulaw2linear ======== * ulaw2linear() - Convert a u-law value to 16-bit linear PCM * * First, a biased linear code is derived from the code word. An unbiased * output can then be obtained by subtracting 33 from the biased code. * * Note that this function expects to be passed the complement of the * original code word. This is in keeping with ISDN conventions. */extern short G711_SUN_ulaw2linear(unsigned char u_val);/* *  ======== alaw2ulaw ======== * A-law to u-law conversion */extern unsigned char G711_SUN_alaw2ulaw(unsigned char aval);/* *  ======== ulaw2alaw ======== *  u-law to A-law conversion */extern unsigned char G711_SUN_ulaw2alaw(unsigned char uval);#endif  /* G711_SUN_ *//* *  @(#) ti.xdais.dm.examples.g711; 1,0,0,20; 10-18-2006 19:11:57; /db/wtree/library/trees/dais-g07x/src/ */