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/* 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 CROSSOVER_H_
#define CROSSOVER_H_
#include <stdbool.h>
#include "biquad.h"
/* An LR4 filter is two biquads with the same parameters connected in series:
*
* x -- [BIQUAD] -- y -- [BIQUAD] -- z
*
* Both biquad filter has the same parameter b[012] and a[12],
* The variable [xyz][12] keep the history values.
*/
struct lr4 {
struct biquad bq;
float x1, x2;
float y1, y2;
float z1, z2;
bool active;
};
void lr4_set(struct lr4 *lr4, enum biquad_type type, float freq);
void lr4_process(struct lr4 *lr4, float *dst, const float *src, const float vol, int samples);
#endif /* CROSSOVER_H_ */
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