libavcodec/ac3dsp.h

Go to the documentation of this file.

/*
 * AC-3 DSP utils
 * Copyright (c) 2011 Justin Ruggles
 *
 * 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_AC3DSP_H
#define AVCODEC_AC3DSP_H

#include <stdint.h>

extern const uint16_t ff_ac3_bap_bits[16];

typedef struct AC3DSPContext {
    void (*ac3_exponent_min)(uint8_t *exp, int num_reuse_blocks, int nb_coefs);

    int (*ac3_max_msb_abs_int16)(const int16_t *src, int len);

    void (*ac3_lshift_int16)(int16_t *src, unsigned int len, unsigned int shift);

    void (*ac3_rshift_int32)(int32_t *src, unsigned int len, unsigned int shift);

    void (*float_to_fixed24)(int32_t *dst, const float *src, unsigned int len);

    void (*bit_alloc_calc_bap)(int16_t *mask, int16_t *psd, int start, int end,
                               int snr_offset, int floor,
                               const uint8_t *bap_tab, uint8_t *bap);

    void (*update_bap_counts)(uint16_t mant_cnt[16], uint8_t *bap, int len);

    int (*compute_mantissa_size)(uint16_t mant_cnt[6][16]);

    void (*extract_exponents)(uint8_t *exp, int32_t *coef, int nb_coefs);
} AC3DSPContext;

void ff_ac3dsp_init    (AC3DSPContext *c, int bit_exact);
void ff_ac3dsp_init_arm(AC3DSPContext *c, int bit_exact);
void ff_ac3dsp_init_x86(AC3DSPContext *c, int bit_exact);

#endif /* AVCODEC_AC3DSP_H */

---