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ffmpeg / libavcodec / ac3dsp.h @ fbb6b49d

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/*
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 * AC-3 DSP utils
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 * Copyright (c) 2011 Justin Ruggles
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef AVCODEC_AC3DSP_H
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#define AVCODEC_AC3DSP_H
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#include <stdint.h>
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typedef struct AC3DSPContext {
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    /**
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     * Set each encoded exponent in a block to the minimum of itself and the
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     * exponents in the same frequency bin of up to 5 following blocks.
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     * @param exp   pointer to the start of the current block of exponents.
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     *              constraints: align 16
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     * @param num_reuse_blocks  number of blocks that will reuse exponents from the current block.
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     *                          constraints: range 0 to 5
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     * @param nb_coefs  number of frequency coefficients.
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     */
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    void (*ac3_exponent_min)(uint8_t *exp, int num_reuse_blocks, int nb_coefs);
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    /**
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     * Calculate the maximum MSB of the absolute value of each element in an
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     * array of int16_t.
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     * @param src input array
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     *            constraints: align 16. values must be in range [-32767,32767]
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     * @param len number of values in the array
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     *            constraints: multiple of 16 greater than 0
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     * @return    a value with the same MSB as max(abs(src[]))
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     */
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    int (*ac3_max_msb_abs_int16)(const int16_t *src, int len);
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} AC3DSPContext;
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void ff_ac3dsp_init    (AC3DSPContext *c);
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void ff_ac3dsp_init_x86(AC3DSPContext *c);
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#endif /* AVCODEC_AC3DSP_H */