dc7e07ac1f
This improves the audio quality significantly for stereo source with both the fixed-point and floating-point AC-3 encoders. Update acodec-ac3_fixed and seek-ac3_rm test references. Originally committed as revision 26271 to svn://svn.ffmpeg.org/ffmpeg/trunk
60 lines
1.9 KiB
C
60 lines
1.9 KiB
C
/*
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* The simplest AC-3 encoder
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* Copyright (c) 2000 Fabrice Bellard
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* Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
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* Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
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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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/**
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* @file
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* fixed-point AC-3 encoder header.
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*/
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#ifndef AVCODEC_AC3ENC_FIXED_H
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#define AVCODEC_AC3ENC_FIXED_H
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#include <stdint.h>
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typedef int16_t SampleType;
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typedef int32_t CoefType;
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typedef int64_t CoefSumType;
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/**
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* Compex number.
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* Used in fixed-point MDCT calculation.
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*/
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typedef struct IComplex {
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int16_t re,im;
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} IComplex;
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typedef struct AC3MDCTContext {
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const int16_t *window; ///< MDCT window function
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int nbits; ///< log2(transform size)
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int16_t *costab; ///< FFT cos table
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int16_t *sintab; ///< FFT sin table
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int16_t *xcos1; ///< MDCT cos table
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int16_t *xsin1; ///< MDCT sin table
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int16_t *rot_tmp; ///< temp buffer for pre-rotated samples
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IComplex *cplx_tmp; ///< temp buffer for complex pre-rotated samples
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} AC3MDCTContext;
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#endif /* AVCODEC_AC3ENC_FIXED_H */
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