lpc.h

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/*
 * LPC subroutine declarations
 */
#define LPC_FILTORDER			10

#define FRAMESIZE	160

typedef struct {
		unsigned short period;
		unsigned char gain;
		char pad;
		signed char k[LPC_FILTORDER];
} lpcparams_t;

/*
 * we can't use 'sizeof(lpcparams_t)' because some compilers
 * add random padding so define size of record that goes over net.
 */
#define LPCRECSIZE 14

typedef struct {
		double Oldper, OldG, Oldk[LPC_FILTORDER + 1], bp[LPC_FILTORDER + 1];
		int pitchctr;
} lpcstate_t;

int lpc_start(void);
void lpc_init(void /*lpcstate_t *state*/);
void lpc_analyze(const unsigned char *buf, lpcparams_t *params);
void lpc_synthesize(unsigned char *buf, lpcparams_t *params, lpcstate_t *state);
void lpc_end(void);