_g72x.h

voip原代码,不过没有电路图,不过可以参考别人的产品自己设计,祝你好运,

int predictor_zero(struct g72x_state *state_ptr);
int predictor_pole(struct g72x_state *state_ptr);
int step_size(struct g72x_state *state_ptr);
int
quantize(
	int		d,	/* Raw difference signal sample */
	int		y,	/* Step size multiplier */
	short		*table,	/* quantization table */
	int		size);	/* table size of short integers */
int
reconstruct(
	int		sign,	/* 0 for non-negative value */
	int		dqln,	/* G.72x codeword */
	int		y);	/* Step size multiplier */
void
update(
	int		code_size,	/* distinguish 723_40 with others */
	int		y,		/* quantizer step size */
	int		wi,		/* scale factor multiplier */
	int		fi,		/* for long/short term energies */
	int		dq,		/* quantized prediction difference */
	int		sr,		/* reconstructed signal */
	int		dqsez,		/* difference from 2-pole predictor */
	struct g72x_state *state_ptr);	/* coder state pointer */
int
tandem_adjust_alaw(
	int		sr,	/* decoder output linear PCM sample */
	int		se,	/* predictor estimate sample */
	int		y,	/* quantizer step size */
	int		i,	/* decoder input code */
	int		sign,
	short		*qtab);
int
tandem_adjust_ulaw(
	int		sr,	/* decoder output linear PCM sample */
	int		se,	/* predictor estimate sample */
	int		y,	/* quantizer step size */
	int		i,	/* decoder input code */
	int		sign,
	short		*qtab);