src/audio/SDL_wave.c
author Sam Lantinga <slouken@libsdl.org>
Tue, 24 Jan 2006 07:20:18 +0000
changeset 1260 80f8c94b5199
parent 769 b8d311d90021
child 1312 c9b51268668f
permissions -rw-r--r--
Date: 10 Jun 2003 15:30:59 -0400 From: Mike Shal Subject: [SDL] Bug in SDL_wave.c? Hey everyone, I'm not sure if this is a bug in SDL, or if I just have incorrect WAV files. The problem I'm having is loading multiple concatenated WAVs from SDL_LoadWAV_RW. Some WAV files put comments at the end of the file (which may be bad form), and SDL doesn't skip past them when reading from the RWops. So the next WAV I try to load will start at the comment section of the previous WAV, which obviously doesn't work. If anyone else is having this problem, one quick fix you can do is run sox on the bad WAVs, which strips out all of the comment sections. Eg: $ sox sound.wav tmp.wav $ mv -f tmp.wav sound.wav The other fix is to patch SDL_wave.c, which is included with this email. (Assuming I made the patch correctly :). All it does is calculate how much remaining space there is in the WAV file after the data chunk, and does SDL_RWseek to skip it. I don't think it should interfere with anything else, but if someone could check it that would be nice :). If the bug is really with SDL and not with my WAVs, can someone work this into the next version of SDL? Thanks, -Mike Shal
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     1
/*
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     2
    SDL - Simple DirectMedia Layer
769
b8d311d90021 Updated copyright information for 2004 (Happy New Year!)
Sam Lantinga <slouken@libsdl.org>
parents: 297
diff changeset
     3
    Copyright (C) 1997-2004 Sam Lantinga
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     4
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     5
    This library is free software; you can redistribute it and/or
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     6
    modify it under the terms of the GNU Library General Public
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     7
    License as published by the Free Software Foundation; either
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     8
    version 2 of the License, or (at your option) any later version.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
     9
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    10
    This library is distributed in the hope that it will be useful,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    11
    but WITHOUT ANY WARRANTY; without even the implied warranty of
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    12
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    13
    Library General Public License for more details.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    14
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    15
    You should have received a copy of the GNU Library General Public
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    16
    License along with this library; if not, write to the Free
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    17
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    18
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    19
    Sam Lantinga
252
e8157fcb3114 Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents: 171
diff changeset
    20
    slouken@libsdl.org
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    21
*/
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    22
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    23
#ifdef SAVE_RCSID
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    24
static char rcsid =
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    25
 "@(#) $Id$";
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    26
#endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    27
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    28
#ifndef DISABLE_FILE
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    29
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    30
/* Microsoft WAVE file loading routines */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    31
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    32
#include <stdlib.h>
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    33
#include <string.h>
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    34
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    35
#include "SDL_error.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    36
#include "SDL_audio.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    37
#include "SDL_wave.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    38
#include "SDL_endian.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    39
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    40
#ifndef NELEMS
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    41
#define NELEMS(array)	((sizeof array)/(sizeof array[0]))
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    42
#endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    43
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    44
static int ReadChunk(SDL_RWops *src, Chunk *chunk);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    45
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    46
struct MS_ADPCM_decodestate {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    47
	Uint8 hPredictor;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    48
	Uint16 iDelta;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    49
	Sint16 iSamp1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    50
	Sint16 iSamp2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    51
};
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    52
static struct MS_ADPCM_decoder {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    53
	WaveFMT wavefmt;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    54
	Uint16 wSamplesPerBlock;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    55
	Uint16 wNumCoef;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    56
	Sint16 aCoeff[7][2];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    57
	/* * * */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    58
	struct MS_ADPCM_decodestate state[2];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    59
} MS_ADPCM_state;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    60
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    61
static int InitMS_ADPCM(WaveFMT *format)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    62
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    63
	Uint8 *rogue_feel;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    64
	Uint16 extra_info;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    65
	int i;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    66
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    67
	/* Set the rogue pointer to the MS_ADPCM specific data */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    68
	MS_ADPCM_state.wavefmt.encoding = SDL_SwapLE16(format->encoding);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    69
	MS_ADPCM_state.wavefmt.channels = SDL_SwapLE16(format->channels);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    70
	MS_ADPCM_state.wavefmt.frequency = SDL_SwapLE32(format->frequency);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    71
	MS_ADPCM_state.wavefmt.byterate = SDL_SwapLE32(format->byterate);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    72
	MS_ADPCM_state.wavefmt.blockalign = SDL_SwapLE16(format->blockalign);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    73
	MS_ADPCM_state.wavefmt.bitspersample =
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    74
					 SDL_SwapLE16(format->bitspersample);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    75
	rogue_feel = (Uint8 *)format+sizeof(*format);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    76
	if ( sizeof(*format) == 16 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    77
		extra_info = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    78
		rogue_feel += sizeof(Uint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    79
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    80
	MS_ADPCM_state.wSamplesPerBlock = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    81
	rogue_feel += sizeof(Uint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    82
	MS_ADPCM_state.wNumCoef = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    83
	rogue_feel += sizeof(Uint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    84
	if ( MS_ADPCM_state.wNumCoef != 7 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    85
		SDL_SetError("Unknown set of MS_ADPCM coefficients");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    86
		return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    87
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    88
	for ( i=0; i<MS_ADPCM_state.wNumCoef; ++i ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    89
		MS_ADPCM_state.aCoeff[i][0] = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    90
		rogue_feel += sizeof(Uint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    91
		MS_ADPCM_state.aCoeff[i][1] = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    92
		rogue_feel += sizeof(Uint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    93
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    94
	return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    95
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    96
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    97
static Sint32 MS_ADPCM_nibble(struct MS_ADPCM_decodestate *state,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    98
					Uint8 nybble, Sint16 *coeff)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
    99
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   100
	const Sint32 max_audioval = ((1<<(16-1))-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   101
	const Sint32 min_audioval = -(1<<(16-1));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   102
	const Sint32 adaptive[] = {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   103
		230, 230, 230, 230, 307, 409, 512, 614,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   104
		768, 614, 512, 409, 307, 230, 230, 230
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   105
	};
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   106
	Sint32 new_sample, delta;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   107
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   108
	new_sample = ((state->iSamp1 * coeff[0]) +
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   109
		      (state->iSamp2 * coeff[1]))/256;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   110
	if ( nybble & 0x08 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   111
		new_sample += state->iDelta * (nybble-0x10);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   112
	} else {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   113
		new_sample += state->iDelta * nybble;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   114
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   115
	if ( new_sample < min_audioval ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   116
		new_sample = min_audioval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   117
	} else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   118
	if ( new_sample > max_audioval ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   119
		new_sample = max_audioval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   120
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   121
	delta = ((Sint32)state->iDelta * adaptive[nybble])/256;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   122
	if ( delta < 16 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   123
		delta = 16;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   124
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   125
	state->iDelta = delta;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   126
	state->iSamp2 = state->iSamp1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   127
	state->iSamp1 = new_sample;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   128
	return(new_sample);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   129
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   130
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   131
static int MS_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   132
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   133
	struct MS_ADPCM_decodestate *state[2];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   134
	Uint8 *freeable, *encoded, *decoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   135
	Sint32 encoded_len, samplesleft;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   136
	Sint8 nybble, stereo;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   137
	Sint16 *coeff[2];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   138
	Sint32 new_sample;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   139
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   140
	/* Allocate the proper sized output buffer */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   141
	encoded_len = *audio_len;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   142
	encoded = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   143
	freeable = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   144
	*audio_len = (encoded_len/MS_ADPCM_state.wavefmt.blockalign) * 
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   145
				MS_ADPCM_state.wSamplesPerBlock*
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   146
				MS_ADPCM_state.wavefmt.channels*sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   147
	*audio_buf = (Uint8 *)malloc(*audio_len);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   148
	if ( *audio_buf == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   149
		SDL_Error(SDL_ENOMEM);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   150
		return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   151
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   152
	decoded = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   153
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   154
	/* Get ready... Go! */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   155
	stereo = (MS_ADPCM_state.wavefmt.channels == 2);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   156
	state[0] = &MS_ADPCM_state.state[0];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   157
	state[1] = &MS_ADPCM_state.state[stereo];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   158
	while ( encoded_len >= MS_ADPCM_state.wavefmt.blockalign ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   159
		/* Grab the initial information for this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   160
		state[0]->hPredictor = *encoded++;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   161
		if ( stereo ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   162
			state[1]->hPredictor = *encoded++;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   163
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   164
		state[0]->iDelta = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   165
		encoded += sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   166
		if ( stereo ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   167
			state[1]->iDelta = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   168
			encoded += sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   169
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   170
		state[0]->iSamp1 = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   171
		encoded += sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   172
		if ( stereo ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   173
			state[1]->iSamp1 = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   174
			encoded += sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   175
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   176
		state[0]->iSamp2 = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   177
		encoded += sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   178
		if ( stereo ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   179
			state[1]->iSamp2 = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   180
			encoded += sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   181
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   182
		coeff[0] = MS_ADPCM_state.aCoeff[state[0]->hPredictor];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   183
		coeff[1] = MS_ADPCM_state.aCoeff[state[1]->hPredictor];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   184
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   185
		/* Store the two initial samples we start with */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   186
		decoded[0] = state[0]->iSamp2&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   187
		decoded[1] = state[0]->iSamp2>>8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   188
		decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   189
		if ( stereo ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   190
			decoded[0] = state[1]->iSamp2&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   191
			decoded[1] = state[1]->iSamp2>>8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   192
			decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   193
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   194
		decoded[0] = state[0]->iSamp1&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   195
		decoded[1] = state[0]->iSamp1>>8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   196
		decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   197
		if ( stereo ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   198
			decoded[0] = state[1]->iSamp1&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   199
			decoded[1] = state[1]->iSamp1>>8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   200
			decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   201
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   202
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   203
		/* Decode and store the other samples in this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   204
		samplesleft = (MS_ADPCM_state.wSamplesPerBlock-2)*
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   205
					MS_ADPCM_state.wavefmt.channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   206
		while ( samplesleft > 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   207
			nybble = (*encoded)>>4;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   208
			new_sample = MS_ADPCM_nibble(state[0],nybble,coeff[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   209
			decoded[0] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   210
			new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   211
			decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   212
			decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   213
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   214
			nybble = (*encoded)&0x0F;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   215
			new_sample = MS_ADPCM_nibble(state[1],nybble,coeff[1]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   216
			decoded[0] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   217
			new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   218
			decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   219
			decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   220
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   221
			++encoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   222
			samplesleft -= 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   223
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   224
		encoded_len -= MS_ADPCM_state.wavefmt.blockalign;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   225
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   226
	free(freeable);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   227
	return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   228
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   229
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   230
struct IMA_ADPCM_decodestate {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   231
	Sint32 sample;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   232
	Sint8 index;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   233
};
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   234
static struct IMA_ADPCM_decoder {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   235
	WaveFMT wavefmt;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   236
	Uint16 wSamplesPerBlock;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   237
	/* * * */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   238
	struct IMA_ADPCM_decodestate state[2];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   239
} IMA_ADPCM_state;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   240
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   241
static int InitIMA_ADPCM(WaveFMT *format)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   242
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   243
	Uint8 *rogue_feel;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   244
	Uint16 extra_info;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   245
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   246
	/* Set the rogue pointer to the IMA_ADPCM specific data */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   247
	IMA_ADPCM_state.wavefmt.encoding = SDL_SwapLE16(format->encoding);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   248
	IMA_ADPCM_state.wavefmt.channels = SDL_SwapLE16(format->channels);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   249
	IMA_ADPCM_state.wavefmt.frequency = SDL_SwapLE32(format->frequency);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   250
	IMA_ADPCM_state.wavefmt.byterate = SDL_SwapLE32(format->byterate);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   251
	IMA_ADPCM_state.wavefmt.blockalign = SDL_SwapLE16(format->blockalign);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   252
	IMA_ADPCM_state.wavefmt.bitspersample =
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   253
					 SDL_SwapLE16(format->bitspersample);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   254
	rogue_feel = (Uint8 *)format+sizeof(*format);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   255
	if ( sizeof(*format) == 16 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   256
		extra_info = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   257
		rogue_feel += sizeof(Uint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   258
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   259
	IMA_ADPCM_state.wSamplesPerBlock = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   260
	return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   261
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   262
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   263
static Sint32 IMA_ADPCM_nibble(struct IMA_ADPCM_decodestate *state,Uint8 nybble)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   264
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   265
	const Sint32 max_audioval = ((1<<(16-1))-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   266
	const Sint32 min_audioval = -(1<<(16-1));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   267
	const int index_table[16] = {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   268
		-1, -1, -1, -1,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   269
		 2,  4,  6,  8,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   270
		-1, -1, -1, -1,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   271
		 2,  4,  6,  8
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   272
	};
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   273
	const Sint32 step_table[89] = {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   274
		7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 21, 23, 25, 28, 31,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   275
		34, 37, 41, 45, 50, 55, 60, 66, 73, 80, 88, 97, 107, 118, 130,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   276
		143, 157, 173, 190, 209, 230, 253, 279, 307, 337, 371, 408,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   277
		449, 494, 544, 598, 658, 724, 796, 876, 963, 1060, 1166, 1282,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   278
		1411, 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, 3327,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   279
		3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132, 7845, 8630,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   280
		9493, 10442, 11487, 12635, 13899, 15289, 16818, 18500, 20350,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   281
		22385, 24623, 27086, 29794, 32767
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   282
	};
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   283
	Sint32 delta, step;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   284
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   285
	/* Compute difference and new sample value */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   286
	step = step_table[state->index];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   287
	delta = step >> 3;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   288
	if ( nybble & 0x04 ) delta += step;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   289
	if ( nybble & 0x02 ) delta += (step >> 1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   290
	if ( nybble & 0x01 ) delta += (step >> 2);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   291
	if ( nybble & 0x08 ) delta = -delta;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   292
	state->sample += delta;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   293
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   294
	/* Update index value */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   295
	state->index += index_table[nybble];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   296
	if ( state->index > 88 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   297
		state->index = 88;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   298
	} else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   299
	if ( state->index < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   300
		state->index = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   301
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   302
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   303
	/* Clamp output sample */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   304
	if ( state->sample > max_audioval ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   305
		state->sample = max_audioval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   306
	} else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   307
	if ( state->sample < min_audioval ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   308
		state->sample = min_audioval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   309
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   310
	return(state->sample);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   311
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   312
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   313
/* Fill the decode buffer with a channel block of data (8 samples) */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   314
static void Fill_IMA_ADPCM_block(Uint8 *decoded, Uint8 *encoded,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   315
	int channel, int numchannels, struct IMA_ADPCM_decodestate *state)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   316
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   317
	int i;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   318
	Sint8 nybble;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   319
	Sint32 new_sample;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   320
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   321
	decoded += (channel * 2);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   322
	for ( i=0; i<4; ++i ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   323
		nybble = (*encoded)&0x0F;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   324
		new_sample = IMA_ADPCM_nibble(state, nybble);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   325
		decoded[0] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   326
		new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   327
		decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   328
		decoded += 2 * numchannels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   329
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   330
		nybble = (*encoded)>>4;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   331
		new_sample = IMA_ADPCM_nibble(state, nybble);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   332
		decoded[0] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   333
		new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   334
		decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   335
		decoded += 2 * numchannels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   336
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   337
		++encoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   338
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   339
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   340
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   341
static int IMA_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   342
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   343
	struct IMA_ADPCM_decodestate *state;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   344
	Uint8 *freeable, *encoded, *decoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   345
	Sint32 encoded_len, samplesleft;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   346
	int c, channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   347
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   348
	/* Check to make sure we have enough variables in the state array */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   349
	channels = IMA_ADPCM_state.wavefmt.channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   350
	if ( channels > NELEMS(IMA_ADPCM_state.state) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   351
		SDL_SetError("IMA ADPCM decoder can only handle %d channels",
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   352
						NELEMS(IMA_ADPCM_state.state));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   353
		return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   354
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   355
	state = IMA_ADPCM_state.state;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   356
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   357
	/* Allocate the proper sized output buffer */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   358
	encoded_len = *audio_len;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   359
	encoded = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   360
	freeable = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   361
	*audio_len = (encoded_len/IMA_ADPCM_state.wavefmt.blockalign) * 
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   362
				IMA_ADPCM_state.wSamplesPerBlock*
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   363
				IMA_ADPCM_state.wavefmt.channels*sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   364
	*audio_buf = (Uint8 *)malloc(*audio_len);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   365
	if ( *audio_buf == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   366
		SDL_Error(SDL_ENOMEM);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   367
		return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   368
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   369
	decoded = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   370
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   371
	/* Get ready... Go! */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   372
	while ( encoded_len >= IMA_ADPCM_state.wavefmt.blockalign ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   373
		/* Grab the initial information for this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   374
		for ( c=0; c<channels; ++c ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   375
			/* Fill the state information for this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   376
			state[c].sample = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   377
			encoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   378
			if ( state[c].sample & 0x8000 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   379
				state[c].sample -= 0x10000;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   380
			}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   381
			state[c].index = *encoded++;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   382
			/* Reserved byte in buffer header, should be 0 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   383
			if ( *encoded++ != 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   384
				/* Uh oh, corrupt data?  Buggy code? */;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   385
			}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   386
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   387
			/* Store the initial sample we start with */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   388
			decoded[0] = state[c].sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   389
			decoded[1] = state[c].sample>>8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   390
			decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   391
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   392
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   393
		/* Decode and store the other samples in this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   394
		samplesleft = (IMA_ADPCM_state.wSamplesPerBlock-1)*channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   395
		while ( samplesleft > 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   396
			for ( c=0; c<channels; ++c ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   397
				Fill_IMA_ADPCM_block(decoded, encoded,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   398
						c, channels, &state[c]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   399
				encoded += 4;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   400
				samplesleft -= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   401
			}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   402
			decoded += (channels * 8 * 2);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   403
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   404
		encoded_len -= IMA_ADPCM_state.wavefmt.blockalign;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   405
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   406
	free(freeable);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   407
	return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   408
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   409
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   410
SDL_AudioSpec * SDL_LoadWAV_RW (SDL_RWops *src, int freesrc,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   411
		SDL_AudioSpec *spec, Uint8 **audio_buf, Uint32 *audio_len)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   412
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   413
	int was_error;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   414
	Chunk chunk;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   415
	int lenread;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   416
	int MS_ADPCM_encoded, IMA_ADPCM_encoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   417
	int samplesize;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   418
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   419
	/* WAV magic header */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   420
	Uint32 RIFFchunk;
1260
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   421
	Uint32 wavelen = 0;
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   422
	Uint32 WAVEmagic;
1260
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   423
	Uint32 headerDiff = 0;
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   424
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   425
	/* FMT chunk */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   426
	WaveFMT *format = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   427
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   428
	/* Make sure we are passed a valid data source */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   429
	was_error = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   430
	if ( src == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   431
		was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   432
		goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   433
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   434
		
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   435
	/* Check the magic header */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   436
	RIFFchunk	= SDL_ReadLE32(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   437
	wavelen		= SDL_ReadLE32(src);
171
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
   438
	if ( wavelen == WAVE ) { /* The RIFFchunk has already been read */
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
   439
		WAVEmagic = wavelen;
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
   440
		wavelen   = RIFFchunk;
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
   441
		RIFFchunk = RIFF;
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
   442
	} else {
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
   443
		WAVEmagic = SDL_ReadLE32(src);
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
   444
	}
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   445
	if ( (RIFFchunk != RIFF) || (WAVEmagic != WAVE) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   446
		SDL_SetError("Unrecognized file type (not WAVE)");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   447
		was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   448
		goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   449
	}
1260
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   450
	headerDiff += sizeof(Uint32); // for WAVE
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   451
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   452
	/* Read the audio data format chunk */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   453
	chunk.data = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   454
	do {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   455
		if ( chunk.data != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   456
			free(chunk.data);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   457
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   458
		lenread = ReadChunk(src, &chunk);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   459
		if ( lenread < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   460
			was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   461
			goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   462
		}
1260
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   463
		// 2 Uint32's for chunk header+len, plus the lenread
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   464
		headerDiff += lenread + 2 * sizeof(Uint32);
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   465
	} while ( (chunk.magic == FACT) || (chunk.magic == LIST) );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   466
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   467
	/* Decode the audio data format */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   468
	format = (WaveFMT *)chunk.data;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   469
	if ( chunk.magic != FMT ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   470
		SDL_SetError("Complex WAVE files not supported");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   471
		was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   472
		goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   473
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   474
	MS_ADPCM_encoded = IMA_ADPCM_encoded = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   475
	switch (SDL_SwapLE16(format->encoding)) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   476
		case PCM_CODE:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   477
			/* We can understand this */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   478
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   479
		case MS_ADPCM_CODE:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   480
			/* Try to understand this */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   481
			if ( InitMS_ADPCM(format) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   482
				was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   483
				goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   484
			}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   485
			MS_ADPCM_encoded = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   486
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   487
		case IMA_ADPCM_CODE:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   488
			/* Try to understand this */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   489
			if ( InitIMA_ADPCM(format) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   490
				was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   491
				goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   492
			}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   493
			IMA_ADPCM_encoded = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   494
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   495
		default:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   496
			SDL_SetError("Unknown WAVE data format: 0x%.4x",
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   497
					SDL_SwapLE16(format->encoding));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   498
			was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   499
			goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   500
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   501
	memset(spec, 0, (sizeof *spec));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   502
	spec->freq = SDL_SwapLE32(format->frequency);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   503
	switch (SDL_SwapLE16(format->bitspersample)) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   504
		case 4:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   505
			if ( MS_ADPCM_encoded || IMA_ADPCM_encoded ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   506
				spec->format = AUDIO_S16;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   507
			} else {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   508
				was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   509
			}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   510
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   511
		case 8:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   512
			spec->format = AUDIO_U8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   513
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   514
		case 16:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   515
			spec->format = AUDIO_S16;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   516
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   517
		default:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   518
			was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   519
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   520
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   521
	if ( was_error ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   522
		SDL_SetError("Unknown %d-bit PCM data format",
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   523
			SDL_SwapLE16(format->bitspersample));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   524
		goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   525
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   526
	spec->channels = (Uint8)SDL_SwapLE16(format->channels);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   527
	spec->samples = 4096;		/* Good default buffer size */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   528
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   529
	/* Read the audio data chunk */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   530
	*audio_buf = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   531
	do {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   532
		if ( *audio_buf != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   533
			free(*audio_buf);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   534
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   535
		lenread = ReadChunk(src, &chunk);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   536
		if ( lenread < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   537
			was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   538
			goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   539
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   540
		*audio_len = lenread;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   541
		*audio_buf = chunk.data;
1260
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   542
		if(chunk.magic != DATA) headerDiff += lenread + 2 * sizeof(Uint32);
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   543
	} while ( chunk.magic != DATA );
1260
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   544
	headerDiff += 2 * sizeof(Uint32); // for the data chunk and len
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   545
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   546
	if ( MS_ADPCM_encoded ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   547
		if ( MS_ADPCM_decode(audio_buf, audio_len) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   548
			was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   549
			goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   550
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   551
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   552
	if ( IMA_ADPCM_encoded ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   553
		if ( IMA_ADPCM_decode(audio_buf, audio_len) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   554
			was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   555
			goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   556
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   557
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   558
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   559
	/* Don't return a buffer that isn't a multiple of samplesize */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   560
	samplesize = ((spec->format & 0xFF)/8)*spec->channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   561
	*audio_len &= ~(samplesize-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   562
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   563
done:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   564
	if ( format != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   565
		free(format);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   566
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   567
	if ( freesrc && src ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   568
		SDL_RWclose(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   569
	}
1260
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   570
	else {
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   571
		// seek to the end of the file (given by the RIFF chunk)
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   572
		SDL_RWseek(src, wavelen - chunk.length - headerDiff, SEEK_CUR);
80f8c94b5199 Date: 10 Jun 2003 15:30:59 -0400
Sam Lantinga <slouken@libsdl.org>
parents: 769
diff changeset
   573
	}
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   574
	if ( was_error ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   575
		spec = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   576
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   577
	return(spec);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   578
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   579
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   580
/* Since the WAV memory is allocated in the shared library, it must also
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   581
   be freed here.  (Necessary under Win32, VC++)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   582
 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   583
void SDL_FreeWAV(Uint8 *audio_buf)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   584
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   585
	if ( audio_buf != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   586
		free(audio_buf);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   587
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   588
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   589
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   590
static int ReadChunk(SDL_RWops *src, Chunk *chunk)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   591
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   592
	chunk->magic	= SDL_ReadLE32(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   593
	chunk->length	= SDL_ReadLE32(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   594
	chunk->data = (Uint8 *)malloc(chunk->length);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   595
	if ( chunk->data == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   596
		SDL_Error(SDL_ENOMEM);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   597
		return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   598
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   599
	if ( SDL_RWread(src, chunk->data, chunk->length, 1) != 1 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   600
		SDL_Error(SDL_EFREAD);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   601
		free(chunk->data);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   602
		return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   603
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   604
	return(chunk->length);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   605
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   606
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   607
#endif /* ENABLE_FILE */