| /* |
| * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| /****************************************************************** |
| |
| iLBC Speech Coder ANSI-C Source Code |
| |
| WebRtcIlbcfix_Chebyshev.h |
| |
| ******************************************************************/ |
| |
| #ifndef MODULES_AUDIO_CODING_CODECS_ILBC_MAIN_SOURCE_CHEBYSHEV_H_ |
| #define MODULES_AUDIO_CODING_CODECS_ILBC_MAIN_SOURCE_CHEBYSHEV_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| /*------------------------------------------------------------------* |
| * Calculate the Chevyshev polynomial series |
| * F(w) = 2*exp(-j5w)*C(x) |
| * C(x) = (T_0(x) + f(1)T_1(x) + ... + f(4)T_1(x) + f(5)/2) |
| * T_i(x) is the i:th order Chebyshev polynomial |
| *------------------------------------------------------------------*/ |
| |
| int16_t WebRtcIlbcfix_Chebyshev( |
| /* (o) Result of C(x) */ |
| int16_t x, /* (i) Value to the Chevyshev polynomial */ |
| int16_t* f /* (i) The coefficients in the polynomial */ |
| ); |
| |
| #endif |
