   
   /******************************************************************
   
       iLBC Speech Coder ANSI-C Source Code
   
       iLBC_define.h    
   
       Copyright (C) The Internet Society (2004). 
       All Rights Reserved.
   
   ******************************************************************/
   #include <string.h>
   
   #ifndef __iLBC_ILBCDEFINE_H
   #define __iLBC_ILBCDEFINE_H
   
   /* general codec settings */
   
   #define FS                      (float)8000.0
   #define BLOCKL_20MS             160
   #define BLOCKL_30MS             240
   #define BLOCKL_MAX              240
   #define NSUB_20MS               4
   #define NSUB_30MS               6
   #define NSUB_MAX            6
   #define NASUB_20MS              2
   #define NASUB_30MS              4
   #define NASUB_MAX               4
   #define SUBL                40
   #define STATE_LEN               80
   #define STATE_SHORT_LEN_30MS    58
   #define STATE_SHORT_LEN_20MS    57
   
   /* LPC settings */
   
   #define LPC_FILTERORDER         10
   #define LPC_CHIRP_SYNTDENUM     (float)0.9025
   #define LPC_CHIRP_WEIGHTDENUM   (float)0.4222
   #define LPC_LOOKBACK        60
   #define LPC_N_20MS              1
   #define LPC_N_30MS              2
   #define LPC_N_MAX               2
   #define LPC_ASYMDIFF        20
   #define LPC_BW                  (float)60.0
   #define LPC_WN                  (float)1.0001
   #define LSF_NSPLIT              3
   
   
   #define LSF_NUMBER_OF_STEPS     4
   #define LPC_HALFORDER           (LPC_FILTERORDER/2)
   
   /* cb settings */
   
   #define CB_NSTAGES              3
   #define CB_EXPAND               2
   #define CB_MEML                 147
   #define CB_FILTERLEN        2*4
   #define CB_HALFFILTERLEN    4
   #define CB_RESRANGE             34
   #define CB_MAXGAIN              (float)1.3 
   
   /* enhancer */
   
   #define ENH_BLOCKL              80  /* block length */
   #define ENH_BLOCKL_HALF         (ENH_BLOCKL/2)
   #define ENH_HL                  3   /* 2*ENH_HL+1 is number blocks
                                          in said second sequence */
   #define ENH_SLOP            2   /* max difference estimated and
                                          correct pitch period */
   #define ENH_PLOCSL              20  /* pitch-estimates and pitch-
                                          locations buffer length */
   #define ENH_OVERHANG        2
   #define ENH_UPS0            4   /* upsampling rate */
   #define ENH_FL0                 3   /* 2*FLO+1 is the length of 
                                          each filter */
   #define ENH_VECTL               (ENH_BLOCKL+2*ENH_FL0)
   #define ENH_CORRDIM             (2*ENH_SLOP+1)
   #define ENH_NBLOCKS             (BLOCKL_MAX/ENH_BLOCKL)
   #define ENH_NBLOCKS_EXTRA       5
   #define ENH_NBLOCKS_TOT         8   /* ENH_NBLOCKS + 
                                          ENH_NBLOCKS_EXTRA */
   #define ENH_BUFL            (ENH_NBLOCKS_TOT)*ENH_BLOCKL
   #define ENH_ALPHA0              (float)0.05
   
   /* Down sampling */
   
   #define FILTERORDER_DS          7
   #define DELAY_DS            3
   #define FACTOR_DS               2
   
   /* bit stream defs */
   
   #define NO_OF_BYTES_20MS    38
   #define NO_OF_BYTES_30MS    50
   #define NO_OF_WORDS_20MS    19
   #define NO_OF_WORDS_30MS    25
   #define STATE_BITS              3
   #define BYTE_LEN            8
   #define ULP_CLASSES             3
   
   /* help parameters */
   
   
   
   #define FLOAT_MAX               (float)1.0e37
   #define EPS                     (float)2.220446049250313e-016
   #define PI                      (float)3.14159265358979323846
   #define MIN_SAMPLE              -32768
   #define MAX_SAMPLE              32767
   #define TWO_PI                  (float)6.283185307
   #define PI2                     (float)0.159154943
   
   /* type definition encoder instance */
   typedef struct iLBC_ULP_Inst_t_ {
       int lsf_bits[6][ULP_CLASSES+2];
       int start_bits[ULP_CLASSES+2];
       int startfirst_bits[ULP_CLASSES+2];
       int scale_bits[ULP_CLASSES+2];
       int state_bits[ULP_CLASSES+2];
       int extra_cb_index[CB_NSTAGES][ULP_CLASSES+2];
       int extra_cb_gain[CB_NSTAGES][ULP_CLASSES+2];
       int cb_index[NSUB_MAX][CB_NSTAGES][ULP_CLASSES+2];
       int cb_gain[NSUB_MAX][CB_NSTAGES][ULP_CLASSES+2];
   } iLBC_ULP_Inst_t;
   
   /* type definition encoder instance */
   typedef struct iLBC_Enc_Inst_t_ {
   
       /* flag for frame size mode */
       int mode;
   
       /* basic parameters for different frame sizes */
       int blockl;
       int nsub;
       int nasub;
       int no_of_bytes, no_of_words;
       int lpc_n;
       int state_short_len;
       const iLBC_ULP_Inst_t *ULP_inst;
   
       /* analysis filter state */
       float anaMem[LPC_FILTERORDER];
   
       /* old lsf parameters for interpolation */
       float lsfold[LPC_FILTERORDER];
       float lsfdeqold[LPC_FILTERORDER];
   
       /* signal buffer for LP analysis */
       float lpc_buffer[LPC_LOOKBACK + BLOCKL_MAX];
   
       /* state of input HP filter */
       float hpimem[4];
   
   } iLBC_Enc_Inst_t;
   
   /* type definition decoder instance */
   typedef struct iLBC_Dec_Inst_t_ {
   
   
   
       /* flag for frame size mode */
       int mode;
   
       /* basic parameters for different frame sizes */
       int blockl;
       int nsub;
       int nasub;
       int no_of_bytes, no_of_words;
       int lpc_n;
       int state_short_len;
       const iLBC_ULP_Inst_t *ULP_inst;
   
       /* synthesis filter state */
       float syntMem[LPC_FILTERORDER];
   
       /* old LSF for interpolation */
       float lsfdeqold[LPC_FILTERORDER];
   
       /* pitch lag estimated in enhancer and used in PLC */
       int last_lag;
   
       /* PLC state information */
       int prevLag, consPLICount, prevPLI, prev_enh_pl;
       float prevLpc[LPC_FILTERORDER+1];
       float prevResidual[NSUB_MAX*SUBL];
       float per;
       unsigned long seed;
   
       /* previous synthesis filter parameters */
       float old_syntdenum[(LPC_FILTERORDER + 1)*NSUB_MAX];
   
       /* state of output HP filter */
       float hpomem[4];
   
       /* enhancer state information */
       int use_enhancer;
       float enh_buf[ENH_BUFL];
       float enh_period[ENH_NBLOCKS_TOT];
   
   } iLBC_Dec_Inst_t;
   
   #endif
   
   
