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/******************************************************************************
*
* Copyright 2022 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************/
/**
* LC3 - Compute LD-MDCT (Low Delay Modified Discret Cosinus Transform)
*
* Reference : Low Complexity Communication Codec (LC3)
* Bluetooth Specification v1.0
*/
#ifndef __LC3_MDCT_H
#define __LC3_MDCT_H
#include "common.h"
/**
* Forward MDCT transformation
* dt, sr Duration and samplerate (size of the transform)
* sr_dst Samplerate destination, scale transforam accordingly
* x, d Temporal samples and delayed buffer
* y, d Output `ns` coefficients and `nd` delayed samples
*
* `x` and `y` can be the same buffer
*/
void lc3_mdct_forward(enum lc3_dt dt, enum lc3_srate sr,
enum lc3_srate sr_dst, const float *x, float *d, float *y);
/**
* Inverse MDCT transformation
* dt, sr Duration and samplerate (size of the transform)
* sr_src Samplerate source, scale transforam accordingly
* x, d Frequency coefficients and delayed buffer
* y, d Output `ns` samples and `nd` delayed ones
*
* `x` and `y` can be the same buffer
*/
void lc3_mdct_inverse(enum lc3_dt dt, enum lc3_srate sr,
enum lc3_srate sr_src, const float *x, float *d, float *y);
#endif /* __LC3_MDCT_H */
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