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
|
/* ScummVM - Scumm Interpreter
* Copyright (C) 2001-2003 The ScummVM project
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* $Header$
*
*/
#ifndef AUDIOSTREAM_H
#define AUDIOSTREAM_H
#include "stdafx.h"
#include "common/scummsys.h"
#include "common/util.h"
/**
* Generic input stream for the resampling code.
*/
class AudioInputStream {
public:
virtual ~AudioInputStream() {}
/**
* Fill the given buffer with up to numSamples samples.
* Returns the actual number of samples read, or -1 if
* a critical error occured (note: you *must* check if
* this value is less than what you requested, this can
* happen when the stream is fully used up).
* For stereo stream, buffer will be filled with interleaved
* left and right channel samples.
*/
virtual int readBuffer(int16 *buffer, const int numSamples) = 0;
/**
* Read a single (16 bit signed) sample from the stream.
*/
virtual int16 read() = 0;
/** Is this a stereo stream? */
virtual bool isStereo() const = 0;
/** End of stream reached? */
virtual bool eos() const = 0;
/** Sample rate of the stream. */
virtual int getRate() const = 0;
};
class WrappedAudioInputStream : public AudioInputStream {
public:
virtual void append(const byte *data, uint32 len) = 0;
virtual void finish() = 0;
};
class ZeroInputStream : public AudioInputStream {
private:
int _len;
public:
ZeroInputStream(uint len) : _len(len) { }
int readBuffer(int16 *buffer, const int numSamples) {
int samples = MIN(_len, numSamples);
memset(buffer, 0, samples * 2);
_len -= samples;
return samples;
}
int16 read() { assert(_len > 0); _len--; return 0; }
bool isStereo() const { return false; }
bool eos() const { return _len <= 0; }
int getRate() const { return -1; }
};
AudioInputStream *makeLinearInputStream(int rate, byte _flags, const byte *ptr, uint32 len, uint loopOffset, uint loopLen);
WrappedAudioInputStream *makeWrappedInputStream(int rate, byte _flags, uint32 len);
#endif
|