drivers/audio/AudioChannel.h

/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
 *   Copyright (C) 2005 - 2007 Christian Schoenebeck                       *
 *                                                                         *
 *   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                                                   *
 ***************************************************************************/

#ifndef __LS_AUDIOCHANNEL_H__
#define __LS_AUDIOCHANNEL_H__

#include <map>
#include <vector>
#include <string.h>
#include "../../common/global.h"
#include "../../common/Exception.h"
#include "../DeviceParameter.h"

namespace LinuxSampler {

    /** Audio Channel (always mono)
     *
     * This class is used for routing audio signals between arbitrary sources
     * and destinations. You can either create a normal channel like:
     * @code
     *  AudioChannel c1(512); // create unnamed channel
     *  AudioChannel c2(512, "Effect send mono channel"); // create named channel
     * @endcode
     * Or you can create a mix channel, e.g. the following would create a
     * normal channel first, and the second channel is just a copy of the
     * first channel:
     * @code
     *  AudioChannel mono_chan(512, "Effect send channel"); // real channel
     *  AudioChannel mix_chan(&mono_chan, "Effect send mono channel"); // mix channel
     * @endcode
     * So in the last example, when writing to 'mix_chan' the signal will
     * actually be mixed to the 'mono_chan' channel, so this is an easy way
     * to downmix a signal source which has more audio channels than the
     * signal destination can offer.
     */
    class AudioChannel {
        public:
            class ParameterName : public DeviceRuntimeParameterString {
                public:
                    ParameterName(String s) : DeviceRuntimeParameterString(s) {}
                    virtual String              Description()           { return "Arbitrary name";      }
                    virtual bool                Fix()                   { return false;                 }
                    virtual std::vector<String> PossibilitiesAsString() { return std::vector<String>(); }
                    virtual void                OnSetValue(String s)    { /* nothing to do */           }
            };

            class ParameterIsMixChannel : public DeviceRuntimeParameterBool {
                public:
                    ParameterIsMixChannel(bool b) : DeviceRuntimeParameterBool(b) {}
                    virtual String Description()                        { return "Whether real channel or mixed to another channel"; }
                    virtual bool   Fix()                                { return true;                                               }
                    virtual void   OnSetValue(bool b) throw (Exception) { /* cannot happen, as parameter is fix */                   }
            };

            class ParameterMixChannelDestination : public DeviceRuntimeParameterInt {
                public:
                    ParameterMixChannelDestination(int i) : DeviceRuntimeParameterInt(i) {}
                    virtual String           Description()                       { return "Destination channel of this mix channel";                 }
                    virtual bool             Fix()                               { return true;                                                      }
                    virtual optional<int>    RangeMinAsInt()                     { return optional<int>::nothing; /*TODO: needs to be implemented */ }
                    virtual optional<int>    RangeMaxAsInt()                     { return optional<int>::nothing; /*TODO: needs to be implemented */ }
                    virtual std::vector<int> PossibilitiesAsInt()                { return std::vector<int>();     /*TODO: needs to be implemented */ }
                    virtual void             OnSetValue(int i) throw (Exception) { /*TODO: needs to be implemented */                                }
            };

            // attributes
            //String Name;  ///< Arbitrary name of this audio channel

            // methods
            inline float*        Buffer()     { return pBuffer;      } ///< Audio signal buffer
            inline AudioChannel* MixChannel() { return pMixChannel;  } ///< In case this channel is a mix channel, then it will return a pointer to the real channel this channel refers to, NULL otherwise.
            inline void          Clear()      { memset(pBuffer, 0, uiBufferSize * sizeof(float)); } ///< Reset audio buffer with silence
            void CopyTo(AudioChannel* pDst, const uint Samples);
            void CopyTo(AudioChannel* pDst, const uint Samples, const float fLevel);
            void MixTo(AudioChannel* pDst, const uint Samples);
            void MixTo(AudioChannel* pDst, const uint Samples, const float fLevel);
            std::map<String,DeviceRuntimeParameter*> ChannelParameters();

            // constructors / destructor
            AudioChannel(uint ChannelNr, uint BufferSize);
            AudioChannel(uint ChannelNr, float* pBuffer, uint BufferSize);
            AudioChannel(uint ChannelNr, AudioChannel* pMixChannelDestination);
            virtual ~AudioChannel();
        protected:
            uint ChannelNr;
            std::map<String,DeviceRuntimeParameter*> Parameters;
        private:
            float*        pBuffer;
            uint          uiBufferSize;
            AudioChannel* pMixChannel;
            bool          UsesExternalBuffer;
    };
}

#endif // __LS_AUDIOCHANNEL_H__
1	/***************************************************************************
2	* *
3	* LinuxSampler - modular, streaming capable sampler *
4	* *
5	* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck *
6	* Copyright (C) 2005 - 2007 Christian Schoenebeck *
7	* *
8	* This program is free software; you can redistribute it and/or modify *
9	* it under the terms of the GNU General Public License as published by *
10	* the Free Software Foundation; either version 2 of the License, or *
11	* (at your option) any later version. *
12	* *
13	* This program is distributed in the hope that it will be useful, *
14	* but WITHOUT ANY WARRANTY; without even the implied warranty of *
15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
16	* GNU General Public License for more details. *
17	* *
18	* You should have received a copy of the GNU General Public License *
19	* along with this program; if not, write to the Free Software *
20	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, *
21	* MA 02111-1307 USA *
22	***************************************************************************/
23
24	#ifndef __LS_AUDIOCHANNEL_H__
25	#define __LS_AUDIOCHANNEL_H__
26
27	#include <map>
28	#include <vector>
29	#include <string.h>
30	#include "../../common/global.h"
31	#include "../../common/Exception.h"
32	#include "../DeviceParameter.h"
33
34	namespace LinuxSampler {
35
36	/** Audio Channel (always mono)
37	*
38	* This class is used for routing audio signals between arbitrary sources
39	* and destinations. You can either create a normal channel like:
40	* @code
41	* AudioChannel c1(512); // create unnamed channel
42	* AudioChannel c2(512, "Effect send mono channel"); // create named channel
43	* @endcode
44	* Or you can create a mix channel, e.g. the following would create a
45	* normal channel first, and the second channel is just a copy of the
46	* first channel:
47	* @code
48	* AudioChannel mono_chan(512, "Effect send channel"); // real channel
49	* AudioChannel mix_chan(&mono_chan, "Effect send mono channel"); // mix channel
50	* @endcode
51	* So in the last example, when writing to 'mix_chan' the signal will
52	* actually be mixed to the 'mono_chan' channel, so this is an easy way
53	* to downmix a signal source which has more audio channels than the
54	* signal destination can offer.
55	*/
56	class AudioChannel {
57	public:
58	class ParameterName : public DeviceRuntimeParameterString {
59	public:
60	ParameterName(String s) : DeviceRuntimeParameterString(s) {}
61	virtual String Description() { return "Arbitrary name"; }
62	virtual bool Fix() { return false; }
63	virtual std::vector<String> PossibilitiesAsString() { return std::vector<String>(); }
64	virtual void OnSetValue(String s) { /* nothing to do */ }
65	};
66
67	class ParameterIsMixChannel : public DeviceRuntimeParameterBool {
68	public:
69	ParameterIsMixChannel(bool b) : DeviceRuntimeParameterBool(b) {}
70	virtual String Description() { return "Whether real channel or mixed to another channel"; }
71	virtual bool Fix() { return true; }
72	virtual void OnSetValue(bool b) throw (Exception) { /* cannot happen, as parameter is fix */ }
73	};
74
75	class ParameterMixChannelDestination : public DeviceRuntimeParameterInt {
76	public:
77	ParameterMixChannelDestination(int i) : DeviceRuntimeParameterInt(i) {}
78	virtual String Description() { return "Destination channel of this mix channel"; }
79	virtual bool Fix() { return true; }
80	virtual optional<int> RangeMinAsInt() { return optional<int>::nothing; /TODO: needs to be implemented / }
81	virtual optional<int> RangeMaxAsInt() { return optional<int>::nothing; /TODO: needs to be implemented / }
82	virtual std::vector<int> PossibilitiesAsInt() { return std::vector<int>(); /TODO: needs to be implemented / }
83	virtual void OnSetValue(int i) throw (Exception) { /TODO: needs to be implemented / }
84	};
85
86	// attributes
87	//String Name; ///< Arbitrary name of this audio channel
88
89	// methods
90	inline float* Buffer() { return pBuffer; } ///< Audio signal buffer
91	inline AudioChannel* MixChannel() { return pMixChannel; } ///< In case this channel is a mix channel, then it will return a pointer to the real channel this channel refers to, NULL otherwise.
92	inline void Clear() { memset(pBuffer, 0, uiBufferSize * sizeof(float)); } ///< Reset audio buffer with silence
93	void CopyTo(AudioChannel* pDst, const uint Samples);
94	void CopyTo(AudioChannel* pDst, const uint Samples, const float fLevel);
95	void MixTo(AudioChannel* pDst, const uint Samples);
96	void MixTo(AudioChannel* pDst, const uint Samples, const float fLevel);
97	std::map<String,DeviceRuntimeParameter*> ChannelParameters();
98
99	// constructors / destructor
100	AudioChannel(uint ChannelNr, uint BufferSize);
101	AudioChannel(uint ChannelNr, float* pBuffer, uint BufferSize);
102	AudioChannel(uint ChannelNr, AudioChannel* pMixChannelDestination);
103	virtual ~AudioChannel();
104	protected:
105	uint ChannelNr;
106	std::map<String,DeviceRuntimeParameter*> Parameters;
107	private:
108	float* pBuffer;
109	uint uiBufferSize;
110	AudioChannel* pMixChannel;
111	bool UsesExternalBuffer;
112	};
113	}
114
115	#endif // __LS_AUDIOCHANNEL_H__