1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program 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 General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*
*/
/**
* Internal interfaces to the ADPCM decoders.
*
* These can be used to make custom ADPCM decoder subclasses,
* or to at least share some common data tables between various
* ADPCM decoder implementations.
*/
#ifndef SOUND_ADPCM_INTERN_H
#define SOUND_ADPCM_INTERN_H
#include "audio/audiostream.h"
#include "common/endian.h"
#include "common/stream.h"
namespace Audio {
class ADPCMStream : public RewindableAudioStream {
protected:
Common::SeekableReadStream *_stream;
const DisposeAfterUse::Flag _disposeAfterUse;
const int32 _startpos;
const int32 _endpos;
const int _channels;
const uint32 _blockAlign;
uint32 _blockPos[2];
const int _rate;
struct ADPCMStatus {
// OKI/IMA
struct {
int32 last;
int32 stepIndex;
} ima_ch[2];
} _status;
virtual void reset();
public:
ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign);
~ADPCMStream();
virtual bool endOfData() const { return (_stream->eos() || _stream->pos() >= _endpos); }
virtual bool isStereo() const { return _channels == 2; }
virtual int getRate() const { return _rate; }
virtual bool rewind();
/**
* This table is used by some ADPCM variants (IMA and OKI) to adjust the
* step for use on the next sample.
* The first 8 entries are identical to the second 8 entries. Hence, we
* could half the table in size. But since the lookup index is always a
* 4-bit nibble, it is more efficient to just keep it as it is.
*/
static const int16 _stepAdjustTable[16];
};
class Oki_ADPCMStream : public ADPCMStream {
public:
Oki_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {}
virtual int readBuffer(int16 *buffer, const int numSamples);
protected:
int16 decodeOKI(byte);
};
class Ima_ADPCMStream : public ADPCMStream {
protected:
int16 decodeIMA(byte code, int channel = 0); // Default to using the left channel/using one channel
public:
Ima_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
memset(&_status, 0, sizeof(_status));
}
/**
* This table is used by decodeIMA.
*/
static const int16 _imaTable[89];
};
class DVI_ADPCMStream : public Ima_ADPCMStream {
public:
DVI_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: Ima_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {}
virtual int readBuffer(int16 *buffer, const int numSamples);
};
class Apple_ADPCMStream : public Ima_ADPCMStream {
protected:
// Apple QuickTime IMA ADPCM
int32 _streamPos[2];
int16 _buffer[2][2];
uint8 _chunkPos[2];
void reset() {
Ima_ADPCMStream::reset();
_chunkPos[0] = 0;
_chunkPos[1] = 0;
_streamPos[0] = 0;
_streamPos[1] = _blockAlign;
}
public:
Apple_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: Ima_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
_chunkPos[0] = 0;
_chunkPos[1] = 0;
_streamPos[0] = 0;
_streamPos[1] = _blockAlign;
}
virtual int readBuffer(int16 *buffer, const int numSamples);
};
class MSIma_ADPCMStream : public Ima_ADPCMStream {
public:
MSIma_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign, bool invertSamples = false)
: Ima_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign), _invertSamples(invertSamples) {
if (blockAlign == 0)
error("ADPCMStream(): blockAlign isn't specified for MS IMA ADPCM");
}
virtual int readBuffer(int16 *buffer, const int numSamples) {
if (_channels == 1)
return readBufferMSIMA1(buffer, numSamples);
else
return readBufferMSIMA2(buffer, numSamples);
}
int readBufferMSIMA1(int16 *buffer, const int numSamples);
int readBufferMSIMA2(int16 *buffer, const int numSamples);
private:
bool _invertSamples; // Some implementations invert the way samples are decoded
};
class MS_ADPCMStream : public ADPCMStream {
protected:
struct ADPCMChannelStatus {
byte predictor;
int16 delta;
int16 coeff1;
int16 coeff2;
int16 sample1;
int16 sample2;
};
struct {
// MS ADPCM
ADPCMChannelStatus ch[2];
} _status;
void reset() {
ADPCMStream::reset();
memset(&_status, 0, sizeof(_status));
}
public:
MS_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
if (blockAlign == 0)
error("MS_ADPCMStream(): blockAlign isn't specified for MS ADPCM");
memset(&_status, 0, sizeof(_status));
}
virtual int readBuffer(int16 *buffer, const int numSamples);
protected:
int16 decodeMS(ADPCMChannelStatus *c, byte);
};
// Duck DK3 IMA ADPCM Decoder
// Based on FFmpeg's decoder and http://wiki.multimedia.cx/index.php?title=Duck_DK3_IMA_ADPCM
class DK3_ADPCMStream : public Ima_ADPCMStream {
protected:
void reset() {
Ima_ADPCMStream::reset();
_topNibble = false;
}
public:
DK3_ADPCMStream(Common::SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse, uint32 size, int rate, int channels, uint32 blockAlign)
: Ima_ADPCMStream(stream, disposeAfterUse, size, rate, channels, blockAlign) {
// DK3 only works as a stereo stream
assert(channels == 2);
_topNibble = false;
}
virtual int readBuffer(int16 *buffer, const int numSamples);
private:
byte _nibble, _lastByte;
bool _topNibble;
};
} // End of namespace Audio
#endif
|
