--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/src/spandsp/private/oki_adpcm.h	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,60 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * private/oki_adpcm.h - Conversion routines between linear 16 bit PCM data
+ *		                 and OKI (Dialogic) ADPCM format.
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2001 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1,
+ * 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: oki_adpcm.h,v 1.1 2008/11/30 10:17:31 steveu Exp $
+ */
+
+/*! \file */
+
+#if !defined(_SPANDSP_PRIVATE_OKI_ADPCM_H_)
+#define _SPANDSP_PRIVATE_OKI_ADPCM_H_
+
+/*!
+    Oki (Dialogic) ADPCM conversion state descriptor. This defines the state of
+    a single working instance of the Oki ADPCM converter. This is used for
+    either linear to ADPCM or ADPCM to linear conversion.
+*/
+struct oki_adpcm_state_s
+{
+    /*! \brief The bit rate - 24000 or 32000. */
+    int bit_rate;
+    /*! \brief The last state of the ADPCM algorithm. */
+    int16_t last;
+    /*! \brief Current index into the step size table. */
+    int16_t step_index;
+    /*! \brief The compressed data byte in progress. */
+    uint8_t oki_byte;
+    /*! \brief The signal history for the sample rate converter. */
+    int16_t history[32];
+    /*! \brief Pointer into the history buffer. */
+    int ptr;
+    /*! \brief Odd/even sample counter. */
+    int mark;
+    /*! \brief Phase accumulator for the sample rate converter. */
+    int phase;
+};
+
+#endif
+/*- End of file ------------------------------------------------------------*/