--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.3/spandsp-0.0.3/src/spandsp/lpc10.h	Fri Jun 25 16:00:21 2010 +0200
@@ -0,0 +1,212 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * lpc10.h - LPC10 low bit rate speech codec.
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2006 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: lpc10.h,v 1.10 2006/11/21 13:57:40 steveu Exp $
+ */
+
+#if !defined(_LPC10_H_)
+#define _LPC10_H_
+
+/*! \page lpc10_page LPC10 encoding and decoding
+\section lpc10_page_sec_1 What does it do?
+The LPC10 module implements the US Department of Defense LPC10
+codec. This codec produces compressed data at 2400bps. At such
+a low rate high fidelity cannot be expected. However, the speech
+clarity is quite good, and this codec is unencumbered by patent
+or other restrictions.
+
+\section lpc10_page_sec_2 How does it work?
+???.
+*/
+
+#define LPC10_SAMPLES_PER_FRAME 180
+#define LPC10_BITS_IN_COMPRESSED_FRAME 54
+
+/*!
+    LPC10 codec unpacked frame.
+*/
+typedef struct
+{
+    int32_t ipitch;
+    int32_t irms;
+    int32_t irc[10];
+} lpc10_frame_t;
+
+/*!
+    LPC10 codec encoder state descriptor. This defines the state of
+    a single working instance of the LPC10 encoder.
+*/
+typedef struct
+{
+    int error_correction;
+
+    /* State used only by function high_pass_100hz */
+    float z11;
+    float z21;
+    float z12;
+    float z22;
+    
+    /* State used by function lpc10_analyse */
+    float inbuf[LPC10_SAMPLES_PER_FRAME*3];
+    float pebuf[LPC10_SAMPLES_PER_FRAME*3];
+    float lpbuf[696];
+    float ivbuf[312];
+    float bias;
+    int32_t osbuf[10];      /* No initial value necessary */
+    int32_t osptr;          /* Initial value 1 */
+    int32_t obound[3];
+    int32_t vwin[3][2];     /* Initial value vwin[2][0] = 307; vwin[2][1] = 462; */
+    int32_t awin[3][2];     /* Initial value awin[2][0] = 307; awin[2][1] = 462; */
+    int32_t voibuf[4][2];
+    float rmsbuf[3];
+    float rcbuf[3][10];
+    float zpre;
+
+    /* State used by function onset */
+    float n;
+    float d__;          /* Initial value 1.0f */
+    float fpc;          /* No initial value necessary */
+    float l2buf[16];
+    float l2sum1;
+    int32_t l2ptr1;     /* Initial value 1 */
+    int32_t l2ptr2;     /* Initial value 9 */
+    int32_t lasti;      /* No initial value necessary */
+    int hyst;           /* Initial value FALSE */
+
+    /* State used by function lpc10_voicing */
+    float dither;       /* Initial value 20.0f */
+    float snr;
+    float maxmin;
+    float voice[3][2];  /* Initial value is probably unnecessary */
+    int32_t lbve;
+    int32_t lbue;
+    int32_t fbve;
+    int32_t fbue;
+    int32_t ofbue;
+    int32_t sfbue;
+    int32_t olbue;
+    int32_t slbue;
+
+    /* State used by function dynamic_pitch_tracking */
+    float s[60];
+    int32_t p[2][60];
+    int32_t ipoint;
+    float alphax;
+
+    /* State used by function lpc10_pack */
+    int32_t isync;
+} lpc10_encode_state_t;
+
+/*!
+    LPC10 codec decoder state descriptor. This defines the state of
+    a single working instance of the LPC10 decoder.
+*/
+typedef struct
+{
+    int error_correction;
+
+    /* State used by function decode */
+    int32_t iptold;     /* Initial value 60 */
+    int first;          /* Initial value TRUE */
+    int32_t ivp2h;
+    int32_t iovoic;
+    int32_t iavgp;      /* Initial value 60 */
+    int32_t erate;
+    int32_t drc[10][3];
+    int32_t dpit[3];
+    int32_t drms[3];
+
+    /* State used by function synths */
+    float buf[LPC10_SAMPLES_PER_FRAME*2];
+    int32_t buflen;     /* Initial value LPC10_SAMPLES_PER_FRAME */
+
+    /* State used by function pitsyn */
+    int32_t ivoico;     /* No initial value necessary as long as first_pitsyn is initially TRUE_ */
+    int32_t ipito;      /* No initial value necessary as long as first_pitsyn is initially TRUE_ */
+    float rmso;         /* Initial value 1.0f */
+    float rco[10];      /* No initial value necessary as long as first_pitsyn is initially TRUE_ */
+    int32_t jsamp;      /* Nno initial value necessary as long as first_pitsyn is initially TRUE_ */
+    int first_pitsyn;   /* Initial value TRUE */
+
+    /* State used by function bsynz */
+    int32_t ipo;
+    float exc[166];
+    float exc2[166];
+    float lpi[3];
+    float hpi[3];
+    float rmso_bsynz;
+
+    /* State used by function random */
+    int32_t j;
+    int32_t k;
+    int16_t y[5];
+
+    /* State used by function deemp */
+    float dei[2];
+    float deo[3];
+} lpc10_decode_state_t;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*! Initialise an LPC10e encode context.
+    \param s The LPC10e context
+    \param error_correction ???
+    \return A pointer to the LPC10e context, or NULL for error. */
+lpc10_encode_state_t *lpc10_encode_init(lpc10_encode_state_t *s, int error_correction);
+
+int lpc10_encode_release(lpc10_encode_state_t *s);
+
+/*! Encode a buffer of linear PCM data to LPC10e.
+    \param s The LPC10e context.
+    \param ima_data The LPC10e data produced.
+    \param amp The audio sample buffer.
+    \param len The number of samples in the buffer.
+    \return The number of bytes of LPC10e data produced. */
+int lpc10_encode(lpc10_encode_state_t *s, uint8_t code[], const int16_t amp[], int quant);
+
+/*! Initialise an LPC10e decode context.
+    \param s The LPC10e context
+    \param error_correction ???
+    \return A pointer to the LPC10e context, or NULL for error. */
+lpc10_decode_state_t *lpc10_decode_init(lpc10_decode_state_t *st, int error_correction);
+
+int lpc10_decode_release(lpc10_decode_state_t *s);
+
+/*! Decode a buffer of LPC10e data to linear PCM.
+    \param s The LPC10e context.
+    \param amp The audio sample buffer.
+    \param code The LPC10e data.
+    \param quant The number of frames of LPC10e data to be decoded.
+    \return The number of samples returned. */
+int lpc10_decode(lpc10_decode_state_t *s, int16_t amp[], const uint8_t code[], int quant);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+/*- End of include ---------------------------------------------------------*/