annotate spandsp-0.0.6pre17/src/spandsp/oki_adpcm.h @ 4:26cd8f1ef0b1

import spandsp-0.0.6pre17
author Peter Meerwald <pmeerw@cosy.sbg.ac.at>
date Fri, 25 Jun 2010 15:50:58 +0200
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26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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1 /*
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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2 * SpanDSP - a series of DSP components for telephony
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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3 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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4 * oki_adpcm.h - Conversion routines between linear 16 bit PCM data and
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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5 * OKI (Dialogic) ADPCM format.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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6 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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7 * Written by Steve Underwood <steveu@coppice.org>
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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8 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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9 * Copyright (C) 2001 Steve Underwood
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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10 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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11 * All rights reserved.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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12 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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13 * This program is free software; you can redistribute it and/or modify
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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14 * it under the terms of the GNU Lesser General Public License version 2.1,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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15 * as published by the Free Software Foundation.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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16 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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17 * This program is distributed in the hope that it will be useful,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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20 * GNU Lesser General Public License for more details.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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21 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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22 * You should have received a copy of the GNU Lesser General Public
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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23 * License along with this program; if not, write to the Free Software
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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25 *
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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26 * $Id: oki_adpcm.h,v 1.24 2009/02/10 13:06:47 steveu Exp $
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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27 */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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28
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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29 /*! \file */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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30
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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31 #if !defined(_SPANDSP_OKI_ADPCM_H_)
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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32 #define _SPANDSP_OKI_ADPCM_H_
26cd8f1ef0b1 import spandsp-0.0.6pre17
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33
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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34 /*! \page okiadpcm_page OKI (Dialogic) ADPCM encoding and decoding
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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35 \section okiadpcm_page_sec_1 What does it do?
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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36 OKI ADPCM is widely used in the CTI industry because it is the principal format
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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37 supported by Dialogic. As the market leader, they tend to define "common
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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38 practice". It offers a good balance of simplicity and quality at rates of
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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39 24kbps or 32kbps. 32kbps is obtained by ADPCM compressing 8k samples/second linear
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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40 PCM. 24kbps is obtained by resampling to 6k samples/second and using the same ADPCM
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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41 compression algorithm on the slower samples.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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42
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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43 The algorithms for this ADPCM codec can be found in "PC Telephony - The complete guide
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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44 to designing, building and programming systems using Dialogic and Related Hardware"
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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45 by Bob Edgar. pg 272-276. */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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46
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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47 /*!
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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48 Oki (Dialogic) ADPCM conversion state descriptor. This defines the state of
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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49 a single working instance of the Oki ADPCM converter. This is used for
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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50 either linear to ADPCM or ADPCM to linear conversion.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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51 */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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52 typedef struct oki_adpcm_state_s oki_adpcm_state_t;
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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53
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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54 #if defined(__cplusplus)
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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55 extern "C"
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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56 {
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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57 #endif
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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58
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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59 /*! Initialise an Oki ADPCM encode or decode context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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60 \param s The Oki ADPCM context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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61 \param bit_rate The required bit rate for the ADPCM data.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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62 The valid rates are 24000 and 32000.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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63 \return A pointer to the Oki ADPCM context, or NULL for error. */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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64 SPAN_DECLARE(oki_adpcm_state_t *) oki_adpcm_init(oki_adpcm_state_t *s,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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65 int bit_rate);
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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66
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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67 /*! Release an Oki ADPCM encode or decode context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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68 \param s The Oki ADPCM context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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69 \return 0 for OK. */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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70 SPAN_DECLARE(int) oki_adpcm_release(oki_adpcm_state_t *s);
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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71
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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72 /*! Free an Oki ADPCM encode or decode context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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73 \param s The Oki ADPCM context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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74 \return 0 for OK. */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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75 SPAN_DECLARE(int) oki_adpcm_free(oki_adpcm_state_t *s);
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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76
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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77 /*! Decode a buffer of Oki ADPCM data to linear PCM.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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78 \param s The Oki ADPCM context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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79 \param amp The audio sample buffer.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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80 \param oki_data
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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81 \param oki_bytes
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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82 \return The number of samples returned. */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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83 SPAN_DECLARE(int) oki_adpcm_decode(oki_adpcm_state_t *s,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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84 int16_t amp[],
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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85 const uint8_t oki_data[],
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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86 int oki_bytes);
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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87
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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88 /*! Encode a buffer of linear PCM data to Oki ADPCM.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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89 \param s The Oki ADPCM context.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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90 \param oki_data The Oki ADPCM data produced
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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91 \param amp The audio sample buffer.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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92 \param len The number of samples in the buffer.
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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93 \return The number of bytes of Oki ADPCM data produced. */
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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94 SPAN_DECLARE(int) oki_adpcm_encode(oki_adpcm_state_t *s,
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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95 uint8_t oki_data[],
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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96 const int16_t amp[],
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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97 int len);
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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98
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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99 #if defined(__cplusplus)
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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100 }
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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101 #endif
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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102
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
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103 #endif
26cd8f1ef0b1 import spandsp-0.0.6pre17
Peter Meerwald <pmeerw@cosy.sbg.ac.at>
parents:
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104 /*- End of file ------------------------------------------------------------*/

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