libavcodec/acelp_filters.h

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/*
 * various filters for ACELP-based codecs
 *
 * Copyright (c) 2008 Vladimir Voroshilov
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVCODEC_ACELP_FILTERS_H
#define AVCODEC_ACELP_FILTERS_H

#include <stdint.h>

typedef struct ACELPFContext {
    void (*acelp_interpolatef)(float *out, const float *in,
                            const float *filter_coeffs, int precision,
                            int frac_pos, int filter_length, int length);

    void (*acelp_apply_order_2_transfer_function)(float *out, const float *in,
                                                  const float zero_coeffs[2],
                                                  const float pole_coeffs[2],
                                                  float gain,
                                                  float mem[2], int n);

}ACELPFContext;

void ff_acelp_filter_init(ACELPFContext *c);
void ff_acelp_filter_init_mips(ACELPFContext *c);

extern const int16_t ff_acelp_interp_filter[61];

void ff_acelp_interpolate(int16_t* out, const int16_t* in,
                          const int16_t* filter_coeffs, int precision,
                          int frac_pos, int filter_length, int length);

void ff_acelp_interpolatef(float *out, const float *in,
                           const float *filter_coeffs, int precision,
                           int frac_pos, int filter_length, int length);


void ff_acelp_high_pass_filter(int16_t* out, int hpf_f[2],
                               const int16_t* in, int length);

void ff_acelp_apply_order_2_transfer_function(float *out, const float *in,
                                              const float zero_coeffs[2],
                                              const float pole_coeffs[2],
                                              float gain,
                                              float mem[2], int n);

void ff_tilt_compensation(float *mem, float tilt, float *samples, int size);


#endif /* AVCODEC_ACELP_FILTERS_H */

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