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
|
/*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* Copyright 2009-2011 Jörg Hermann Müller
*
* This file is part of AudaSpace.
*
* Audaspace 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.
*
* AudaSpace 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 Audaspace; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* ***** END GPL LICENSE BLOCK *****
*/
/** \file audaspace/FX/AUD_ReverseReader.cpp
* \ingroup audfx
*/
#include "AUD_ReverseReader.h"
#include <cstring>
static const char* props_error = "AUD_ReverseReader: The reader has to be "
"seekable and a finite length.";
AUD_ReverseReader::AUD_ReverseReader(boost::shared_ptr<AUD_IReader> reader) :
AUD_EffectReader(reader),
m_length(reader->getLength()),
m_position(0)
{
if(m_length < 0 || !reader->isSeekable())
AUD_THROW(AUD_ERROR_PROPS, props_error);
}
void AUD_ReverseReader::seek(int position)
{
m_position = position;
}
int AUD_ReverseReader::getLength() const
{
return m_length;
}
int AUD_ReverseReader::getPosition() const
{
return m_position;
}
void AUD_ReverseReader::read(int& length, bool& eos, sample_t* buffer)
{
// first correct the length
if(m_position + length > m_length)
length = m_length - m_position;
if(length <= 0)
{
length = 0;
eos = true;
return;
}
const AUD_Specs specs = getSpecs();
const int samplesize = AUD_SAMPLE_SIZE(specs);
sample_t temp[AUD_CHANNEL_MAX];
int len = length;
// read from reader
m_reader->seek(m_length - m_position - len);
m_reader->read(len, eos, buffer);
// set null if reader didn't give enough data
if(len < length)
memset(buffer, 0, (length - len) * samplesize);
// copy the samples reverted
for(int i = 0; i < length / 2; i++)
{
memcpy(temp,
buffer + (len - 1 - i) * specs.channels,
samplesize);
memcpy(buffer + (len - 1 - i) * specs.channels,
buffer + i * specs.channels,
samplesize);
memcpy(buffer + i * specs.channels,
temp,
samplesize);
}
m_position += length;
eos = false;
}
|
