dsp_sub.h

2400bps MELP语音编解码源程序。

/*

2.4 kbps MELP Proposed Federal Standard speech coder

Fixed-point C code, version 1.0

Copyright (c) 1998, Texas Instruments, Inc.  

Texas Instruments has intellectual property rights on the MELP
algorithm.  The Texas Instruments contact for licensing issues for
commercial and non-government use is William Gordon, Director,
Government Contracts, Texas Instruments Incorporated, Semiconductor
Group (phone [phone]).

The fixed-point version of the voice codec Mixed Excitation Linear
Prediction (MELP) is based on specifications on the C-language software
simulation contained in GSM 06.06 which is protected by copyright and
is the property of the European Telecommunications Standards Institute
(ETSI). This standard is available from the ETSI publication office
tel. [phone]. ETSI has granted a license to United States
Department of Defense to use the C-language software simulation contained
in GSM 06.06 for the purposes of the development of a fixed-point
version of the voice codec Mixed Excitation Linear Prediction (MELP).
Requests for authorization to make other use of the GSM 06.06 or
otherwise distribute or modify them need to be addressed to the ETSI
Secretariat fax: [phone].

*/
/*

  dsp_sub.h: include file 
  
*/

#ifndef _dsp_sub_h
#define _dsp_sub_h_

/* External function definitions */
void envelope(Shortword input[], Shortword prev_in, Shortword output[], 
	      Shortword npts);
void fill(Shortword output[], Shortword fillval, Shortword npts);
void interp_array(Shortword prev[],Shortword curr[],Shortword out[],
		  Shortword ifact,Shortword size);
Shortword median(Shortword input[], Shortword npts);
void pack_code(Shortword code,UShortword **p_ch_beg,Shortword *p_ch_bit, 
	       Shortword numbits,Shortword wsize);
Shortword peakiness(Shortword input[], Shortword npts);
void quant_u(Shortword *p_data, Shortword *p_index, Shortword qmin, 
	     Shortword qmax, Shortword nlev, Shortword nlev_q, 
	     Shortword double_flag, Shortword scale);
void quant_u_dec(Shortword index, Shortword *p_data, Shortword qmin, 
		 Shortword qmax, Shortword nlev_q, Shortword scale);
void rand_num(Shortword output[], Shortword amplitude, Shortword npts);
Shortword readbl(Shortword input[], FILE *fp_in, Shortword size);
Shortword unpack_code(UShortword **p_ch_beg, Shortword *p_ch_bit, 
		      Shortword *p_code, Shortword numbits, Shortword wsize, 
		      UShortword erase_mask);
void window(Shortword input[], Shortword win_cof[], 
	    Shortword output[], Shortword npts);
void window_Q(Shortword input[], Shortword win_cof[], 
	      Shortword output[], Shortword npts, Shortword Qin);
void writebl(Shortword output[], FILE *fp_out, Shortword size);
void zerflt(Shortword input[], Shortword coeff[], Shortword output[], 
	    Shortword order, Shortword npts);
void zerflt_Q(Shortword input[], Shortword coeff[], Shortword output[], 
	      Shortword order, Shortword npts, Shortword Q_coeff);
void iir_2nd_d(Shortword input[],Shortword den[],Shortword num[],
	       Shortword output[],Shortword delin[],Shortword delout_hi[],
	       Shortword delout_lo[],Shortword npts);
void iir_2nd_s(Shortword input[],Shortword den[],Shortword num[],
	       Shortword output[],Shortword delin[],Shortword delout[],
	       Shortword npts);

#endif