1b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org/*
2b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *
4b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  Use of this source code is governed by a BSD-style license
5b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  that can be found in the LICENSE file in the root of the source
6b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  tree. An additional intellectual property rights grant can be found
7b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  in the file PATENTS.  All contributing project authors may
8b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  be found in the AUTHORS file in the root of the source tree.
9b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org */
10b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
11b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org/******************************************************************
12b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
13b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org iLBC Speech Coder ANSI-C Source Code
14b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
15b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org WebRtcIlbcfix_Chebyshev.h
16b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
17b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org******************************************************************/
18b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
19b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org#ifndef WEBRTC_MODULES_AUDIO_CODING_CODECS_ILBC_MAIN_SOURCE_CHEBYSHEV_H_
20b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org#define WEBRTC_MODULES_AUDIO_CODING_CODECS_ILBC_MAIN_SOURCE_CHEBYSHEV_H_
21b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
22b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org#include "defines.h"
23b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
24b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org/*------------------------------------------------------------------*
25b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  Calculate the Chevyshev polynomial series
26b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *  F(w) = 2*exp(-j5w)*C(x)
27b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *   C(x) = (T_0(x) + f(1)T_1(x) + ... + f(4)T_1(x) + f(5)/2)
28b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *   T_i(x) is the i:th order Chebyshev polynomial
29b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org *------------------------------------------------------------------*/
30b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
31fbda0fcf2f9e82c82bcaac138f44d4e5144f6e0dpbos@webrtc.orgint16_t WebRtcIlbcfix_Chebyshev(
32b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org    /* (o) Result of C(x) */
33fbda0fcf2f9e82c82bcaac138f44d4e5144f6e0dpbos@webrtc.org    int16_t x,  /* (i) Value to the Chevyshev polynomial */
34fbda0fcf2f9e82c82bcaac138f44d4e5144f6e0dpbos@webrtc.org    int16_t *f  /* (i) The coefficients in the polynomial */
35b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org                                      );
36b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org
37b015cbede88899f67a53fbbe581b02ce8e32794andrew@webrtc.org#endif
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