opus_multistream.c revision 2bd8b54017b5320bc0c1df9bf86f4cdc9f8db242 
1/* Copyright (c) 2011 Xiph.Org Foundation
2   Written by Jean-Marc Valin */
3/*
4   Redistribution and use in source and binary forms, with or without
5   modification, are permitted provided that the following conditions
6   are met:
7
8   - Redistributions of source code must retain the above copyright
9   notice, this list of conditions and the following disclaimer.
10
11   - Redistributions in binary form must reproduce the above copyright
12   notice, this list of conditions and the following disclaimer in the
13   documentation and/or other materials provided with the distribution.
14
15   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
19   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
22   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
23   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
24   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26*/
27
28#ifdef HAVE_CONFIG_H
29#include "config.h"
30#endif
31
32#include "opus_multistream.h"
33#include "opus.h"
34#include "opus_private.h"
35#include "stack_alloc.h"
36#include <stdarg.h>
37#include "float_cast.h"
38#include "os_support.h"
39
40
41int validate_layout(const ChannelLayout *layout)
42{
43   int i, max_channel;
44
45   max_channel = layout->nb_streams+layout->nb_coupled_streams;
46   if (max_channel>255)
47      return 0;
48   for (i=0;i<layout->nb_channels;i++)
49   {
50      if (layout->mapping[i] >= max_channel && layout->mapping[i] != 255)
51         return 0;
52   }
53   return 1;
54}
55
56
57int get_left_channel(const ChannelLayout *layout, int stream_id, int prev)
58{
59   int i;
60   i = (prev<0) ? 0 : prev+1;
61   for (;i<layout->nb_channels;i++)
62   {
63      if (layout->mapping[i]==stream_id*2)
64         return i;
65   }
66   return -1;
67}
68
69int get_right_channel(const ChannelLayout *layout, int stream_id, int prev)
70{
71   int i;
72   i = (prev<0) ? 0 : prev+1;
73   for (;i<layout->nb_channels;i++)
74   {
75      if (layout->mapping[i]==stream_id*2+1)
76         return i;
77   }
78   return -1;
79}
80
81int get_mono_channel(const ChannelLayout *layout, int stream_id, int prev)
82{
83   int i;
84   i = (prev<0) ? 0 : prev+1;
85   for (;i<layout->nb_channels;i++)
86   {
87      if (layout->mapping[i]==stream_id+layout->nb_coupled_streams)
88         return i;
89   }
90   return -1;
91}
92
93