silk/define.h

/***********************************************************************
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***********************************************************************/

#ifndef SILK_DEFINE_H
#define SILK_DEFINE_H

#include "errors.h"
#include "typedef.h"

#ifdef __cplusplus
extern "C"
{
#endif

/* Max number of encoder channels (1/2) */
#define ENCODER_NUM_CHANNELS                    2
/* Number of decoder channels (1/2) */
#define DECODER_NUM_CHANNELS                    2

#define MAX_FRAMES_PER_PACKET                   3

/* Limits on bitrate */
#define MIN_TARGET_RATE_BPS                     5000
#define MAX_TARGET_RATE_BPS                     80000
#define TARGET_RATE_TAB_SZ                      8

/* LBRR thresholds */
#define LBRR_NB_MIN_RATE_BPS                    12000
#define LBRR_MB_MIN_RATE_BPS                    14000
#define LBRR_WB_MIN_RATE_BPS                    16000

/* DTX settings */
#define NB_SPEECH_FRAMES_BEFORE_DTX             10      /* eq 200 ms */
#define MAX_CONSECUTIVE_DTX                     20      /* eq 400 ms */
#define DTX_ACTIVITY_THRESHOLD                  0.1f

/* Maximum sampling frequency */
#define MAX_FS_KHZ                              16
#define MAX_API_FS_KHZ                          48

/* Signal types */
#define TYPE_NO_VOICE_ACTIVITY                  0
#define TYPE_UNVOICED                           1
#define TYPE_VOICED                             2

/* Conditional coding types */
#define CODE_INDEPENDENTLY                      0
#define CODE_INDEPENDENTLY_NO_LTP_SCALING       1
#define CODE_CONDITIONALLY                      2

/* Settings for stereo processing */
#define STEREO_QUANT_TAB_SIZE                   16
#define STEREO_QUANT_SUB_STEPS                  5
#define STEREO_INTERP_LEN_MS                    8       /* must be even */
#define STEREO_RATIO_SMOOTH_COEF                0.01    /* smoothing coef for signal norms and stereo width */

/* Range of pitch lag estimates */
#define PITCH_EST_MIN_LAG_MS                    2       /* 2 ms -> 500 Hz */
#define PITCH_EST_MAX_LAG_MS                    18      /* 18 ms -> 56 Hz */

/* Maximum number of subframes */
#define MAX_NB_SUBFR                            4

/* Number of samples per frame */
#define LTP_MEM_LENGTH_MS                       20
#define SUB_FRAME_LENGTH_MS                     5
#define MAX_SUB_FRAME_LENGTH                    ( SUB_FRAME_LENGTH_MS * MAX_FS_KHZ )
#define MAX_FRAME_LENGTH_MS                     ( SUB_FRAME_LENGTH_MS * MAX_NB_SUBFR )
#define MAX_FRAME_LENGTH                        ( MAX_FRAME_LENGTH_MS * MAX_FS_KHZ )

/* Milliseconds of lookahead for pitch analysis */
#define LA_PITCH_MS                             2
#define LA_PITCH_MAX                            ( LA_PITCH_MS * MAX_FS_KHZ )

/* Order of LPC used in find pitch */
#define MAX_FIND_PITCH_LPC_ORDER                16

/* Length of LPC window used in find pitch */
#define FIND_PITCH_LPC_WIN_MS                   ( 20 + (LA_PITCH_MS << 1) )
#define FIND_PITCH_LPC_WIN_MS_2_SF              ( 10 + (LA_PITCH_MS << 1) )
#define FIND_PITCH_LPC_WIN_MAX                  ( FIND_PITCH_LPC_WIN_MS * MAX_FS_KHZ )

/* Milliseconds of lookahead for noise shape analysis */
#define LA_SHAPE_MS                             5
#define LA_SHAPE_MAX                            ( LA_SHAPE_MS * MAX_FS_KHZ )

/* Maximum length of LPC window used in noise shape analysis */
#define SHAPE_LPC_WIN_MAX                       ( 15 * MAX_FS_KHZ )

/* dB level of lowest gain quantization level */
#define MIN_QGAIN_DB                            2
/* dB level of highest gain quantization level */
#define MAX_QGAIN_DB                            88
/* Number of gain quantization levels */
#define N_LEVELS_QGAIN                          64
/* Max increase in gain quantization index */
#define MAX_DELTA_GAIN_QUANT                    36
/* Max decrease in gain quantization index */
#define MIN_DELTA_GAIN_QUANT                    -4

/* Quantization offsets (multiples of 4) */
#define OFFSET_VL_Q10                           32
#define OFFSET_VH_Q10                           100
#define OFFSET_UVL_Q10                          100
#define OFFSET_UVH_Q10                          240

#define QUANT_LEVEL_ADJUST_Q10                  80

/* Maximum numbers of iterations used to stabilize an LPC vector */
#define MAX_LPC_STABILIZE_ITERATIONS            16
#define MAX_PREDICTION_POWER_GAIN               1e4f
#define MAX_PREDICTION_POWER_GAIN_AFTER_RESET   1e2f

#define MAX_LPC_ORDER                           16
#define MIN_LPC_ORDER                           10

/* Find Pred Coef defines */
#define LTP_ORDER                               5

/* LTP quantization settings */
#define NB_LTP_CBKS                             3

/* Flag to use harmonic noise shaping */
#define USE_HARM_SHAPING                        1

/* Max LPC order of noise shaping filters */
#define MAX_SHAPE_LPC_ORDER                     24

#define HARM_SHAPE_FIR_TAPS                     3

/* Maximum number of delayed decision states */
#define MAX_DEL_DEC_STATES                      4

#define LTP_BUF_LENGTH                          512
#define LTP_MASK                                ( LTP_BUF_LENGTH - 1 )

#define DECISION_DELAY                          40

/* Number of subframes for excitation entropy coding */
#define SHELL_CODEC_FRAME_LENGTH                16
#define LOG2_SHELL_CODEC_FRAME_LENGTH           4
#define MAX_NB_SHELL_BLOCKS                     ( MAX_FRAME_LENGTH / SHELL_CODEC_FRAME_LENGTH )

/* Number of rate levels, for entropy coding of excitation */
#define N_RATE_LEVELS                           10

/* Maximum sum of pulses per shell coding frame */
#define SILK_MAX_PULSES                         16

#define MAX_MATRIX_SIZE                         MAX_LPC_ORDER /* Max of LPC Order and LTP order */

# define NSQ_LPC_BUF_LENGTH                     MAX_LPC_ORDER

/***************************/
/* Voice activity detector */
/***************************/
#define VAD_N_BANDS                             4

#define VAD_INTERNAL_SUBFRAMES_LOG2             2
#define VAD_INTERNAL_SUBFRAMES                  ( 1 << VAD_INTERNAL_SUBFRAMES_LOG2 )

#define VAD_NOISE_LEVEL_SMOOTH_COEF_Q16         1024    /* Must be <  4096 */
#define VAD_NOISE_LEVELS_BIAS                   50

/* Sigmoid settings */
#define VAD_NEGATIVE_OFFSET_Q5                  128     /* sigmoid is 0 at -128 */
#define VAD_SNR_FACTOR_Q16                      45000

/* smoothing for SNR measurement */
#define VAD_SNR_SMOOTH_COEF_Q18                 4096

/* Size of the piecewise linear cosine approximation table for the LSFs */
#define LSF_COS_TAB_SZ_FIX                      128

/******************/
/* NLSF quantizer */
/******************/
#define NLSF_W_Q                                2
#define NLSF_VQ_MAX_VECTORS                     32
#define NLSF_QUANT_MAX_AMPLITUDE                4
#define NLSF_QUANT_MAX_AMPLITUDE_EXT            10
#define NLSF_QUANT_LEVEL_ADJ                    0.1
#define NLSF_QUANT_DEL_DEC_STATES_LOG2          2
#define NLSF_QUANT_DEL_DEC_STATES               ( 1 << NLSF_QUANT_DEL_DEC_STATES_LOG2 )

/* Transition filtering for mode switching */
#define TRANSITION_TIME_MS                      5120    /* 5120 = 64 * FRAME_LENGTH_MS * ( TRANSITION_INT_NUM - 1 ) = 64*(20*4)*/
#define TRANSITION_NB                           3       /* Hardcoded in tables */
#define TRANSITION_NA                           2       /* Hardcoded in tables */
#define TRANSITION_INT_NUM                      5       /* Hardcoded in tables */
#define TRANSITION_FRAMES                       ( TRANSITION_TIME_MS / MAX_FRAME_LENGTH_MS )
#define TRANSITION_INT_STEPS                    ( TRANSITION_FRAMES  / ( TRANSITION_INT_NUM - 1 ) )

/* BWE factors to apply after packet loss */
#define BWE_AFTER_LOSS_Q16                      63570

/* Defines for CN generation */
#define CNG_BUF_MASK_MAX                        255     /* 2^floor(log2(MAX_FRAME_LENGTH))-1    */
#define CNG_GAIN_SMTH_Q16                       4634    /* 0.25^(1/4)                           */
#define CNG_NLSF_SMTH_Q16                       16348   /* 0.25                                 */

#ifdef __cplusplus
}
#endif

#endif