| /* Copyright (c) 2013 The Chromium OS Authors. All rights reserved. |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef DCBLOCK_H_ |
| #define DCBLOCK_H_ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /* A DC blocking filter. */ |
| |
| struct dcblock; |
| |
| /* |
| * Create a DC blocking filter. |
| * |
| * Transfer fn: (1 - z^-1) / (1 - R * z^-1) |
| * Args: |
| * R - DC block filter coefficient. |
| * sample_rate - The sample rate, in Hz. |
| */ |
| struct dcblock *dcblock_new(float R, unsigned long sample_rate); |
| |
| /* Free a DC blocking filter. */ |
| void dcblock_free(struct dcblock *dcblock); |
| |
| /* Process a buffer of audio data through the filter. |
| * Args: |
| * dcblock - The filter we want to use. |
| * data - The array of audio samples. |
| * count - The number of elements in the data array to process. |
| */ |
| void dcblock_process(struct dcblock *dcblock, float *data, int count); |
| |
| #ifdef __cplusplus |
| } /* extern "C" */ |
| #endif |
| |
| #endif /* DCBLOCK_H_ */ |
