view src/audio/SDL_wave.h @ 2659:8da698bc1205 gsoc2008_audio_resampling

Fixed lots of bugs in FIR filtering. Fixed point code is closer to working, but there seems to be overflow in the FIR filter resulting in distortion.
author Aaron Wishnick <schnarf@gmail.com>
date Sun, 22 Jun 2008 00:36:35 +0000
parents 6abc7e6f9817
children 99210400e8b9
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is SDL_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.

    This library 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 this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* WAVE files are little-endian */

/*******************************************/
/* Define values for Microsoft WAVE format */
/*******************************************/
#define RIFF		0x46464952      /* "RIFF" */
#define WAVE		0x45564157      /* "WAVE" */
#define FACT		0x74636166      /* "fact" */
#define LIST		0x5453494c      /* "LIST" */
#define FMT		0x20746D66      /* "fmt " */
#define DATA		0x61746164      /* "data" */
#define PCM_CODE	0x0001
#define MS_ADPCM_CODE	0x0002
#define IEEE_FLOAT_CODE	0x0003
#define IMA_ADPCM_CODE	0x0011
#define MP3_CODE	0x0055
#define WAVE_MONO	1
#define WAVE_STEREO	2

/* Normally, these three chunks come consecutively in a WAVE file */
typedef struct WaveFMT
{
/* Not saved in the chunk we read:
	Uint32	FMTchunk;
	Uint32	fmtlen;
*/
    Uint16 encoding;
    Uint16 channels;            /* 1 = mono, 2 = stereo */
    Uint32 frequency;           /* One of 11025, 22050, or 44100 Hz */
    Uint32 byterate;            /* Average bytes per second */
    Uint16 blockalign;          /* Bytes per sample block */
    Uint16 bitspersample;       /* One of 8, 12, 16, or 4 for ADPCM */
} WaveFMT;

/* The general chunk found in the WAVE file */
typedef struct Chunk
{
    Uint32 magic;
    Uint32 length;
    Uint8 *data;
} Chunk;
/* vi: set ts=4 sw=4 expandtab: */