mirror of
https://github.com/xenia-project/FFmpeg.git
synced 2024-11-24 12:09:55 +00:00
82 lines
2.3 KiB
C
82 lines
2.3 KiB
C
/*
|
|
* ADX ADPCM codecs
|
|
* Copyright (c) 2001,2003 BERO
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav 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.
|
|
*
|
|
* Libav 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 Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* SEGA CRI adx codecs.
|
|
*
|
|
* Reference documents:
|
|
* http://ku-www.ss.titech.ac.jp/~yatsushi/adx.html
|
|
* adx2wav & wav2adx http://www.geocities.co.jp/Playtown/2004/
|
|
*/
|
|
|
|
#ifndef AVCODEC_ADX_H
|
|
#define AVCODEC_ADX_H
|
|
|
|
#include <stdint.h>
|
|
|
|
#include "avcodec.h"
|
|
|
|
typedef struct ADXChannelState {
|
|
int s1,s2;
|
|
} ADXChannelState;
|
|
|
|
typedef struct ADXContext {
|
|
AVFrame frame;
|
|
int channels;
|
|
ADXChannelState prev[2];
|
|
int header_parsed;
|
|
int eof;
|
|
int cutoff;
|
|
int coeff[2];
|
|
} ADXContext;
|
|
|
|
#define COEFF_BITS 12
|
|
|
|
#define BLOCK_SIZE 18
|
|
#define BLOCK_SAMPLES 32
|
|
|
|
/**
|
|
* Calculate LPC coefficients based on cutoff frequency and sample rate.
|
|
*
|
|
* @param cutoff cutoff frequency
|
|
* @param sample_rate sample rate
|
|
* @param bits number of bits used to quantize coefficients
|
|
* @param[out] coeff 2 quantized LPC coefficients
|
|
*/
|
|
void ff_adx_calculate_coeffs(int cutoff, int sample_rate, int bits, int *coeff);
|
|
|
|
/**
|
|
* Decode ADX stream header.
|
|
* Sets avctx->channels and avctx->sample_rate.
|
|
*
|
|
* @param avctx codec context
|
|
* @param buf header data
|
|
* @param bufsize data size, should be at least 24 bytes
|
|
* @param[out] header_size size of ADX header
|
|
* @param[out] coeff 2 LPC coefficients, can be NULL
|
|
* @return data offset or negative error code if header is invalid
|
|
*/
|
|
int avpriv_adx_decode_header(AVCodecContext *avctx, const uint8_t *buf,
|
|
int bufsize, int *header_size, int *coeff);
|
|
|
|
#endif /* AVCODEC_ADX_H */
|