From 0b33c344fffbcc83eaf55bc6e5010549297b0dd0 Mon Sep 17 00:00:00 2001
From: Craig Hansen-Sturm <chansensturm@comcast.net>
Date: Sat, 6 Sep 2014 02:18:35 -0700
Subject: [PATCH] new audio buffer object

---
 libraries/audio/src/AudioBuffer.h | 174 ++++++++++++++++++++++++++++++
 1 file changed, 174 insertions(+)
 create mode 100644 libraries/audio/src/AudioBuffer.h

diff --git a/libraries/audio/src/AudioBuffer.h b/libraries/audio/src/AudioBuffer.h
new file mode 100644
index 0000000000..dd0030ecd8
--- /dev/null
+++ b/libraries/audio/src/AudioBuffer.h
@@ -0,0 +1,174 @@
+//
+//  AudioBuffer.h
+//  hifi
+//
+//  Created by Craig Hansen-Sturm on 8/29/14.
+//  Copyright 2014 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#ifndef hifi_AudioBuffer_h
+#define hifi_AudioBuffer_h
+
+#include <typeinfo>
+
+template< typename T >
+class AudioFrameBuffer {
+    
+    uint16_t _channelCount;
+    uint16_t _frameCount;
+    uint16_t _frameCountMax;
+    
+    T** _frameBuffer;
+
+    void allocateFrames() {
+        _frameBuffer = new T*[_channelCount];
+        if (_frameBuffer) {
+            for (uint16_t i = 0; i < _channelCount; ++i) {
+                _frameBuffer[i] = new T[_frameCountMax];
+            }
+        }
+    }
+    
+    void deallocateFrames() {
+        if (_frameBuffer) {
+            for (uint16_t i = 0; i < _channelCount; ++i) {
+                delete _frameBuffer[i];
+            }
+            delete _frameBuffer;
+        }
+        _frameBuffer = NULL;
+    }
+    
+public:
+    
+    AudioFrameBuffer() 
+    : _channelCount(0)
+    , _frameCount(0)
+    , _frameCountMax(0)
+    , _frameBuffer(NULL) {
+    }
+    
+    AudioFrameBuffer(const uint16_t channelCount, const uint16_t frameCount) 
+    : _channelCount(channelCount)
+    , _frameCount(frameCount)
+    , _frameCountMax(frameCount)
+    , _frameBuffer(NULL) {
+        allocateFrames();
+    }
+    
+    ~AudioFrameBuffer() {
+        finalize();
+    }
+    
+    void initialize(const uint16_t channelCount, const uint16_t frameCount) {
+        if (_frameBuffer) {
+            finalize();
+        }
+        _channelCount = channelCount;
+        _frameCount = frameCount;
+        _frameCountMax = frameCount;
+        allocateFrames();
+    }
+    
+    void finalize() {
+        deallocateFrames();
+        _channelCount = 0;
+        _frameCount = 0;
+    }
+                
+    T**& getFrameData() {
+        return _frameBuffer;
+    }
+    
+    uint16_t getChannelCount() {
+        return _channelCount;
+    }
+    
+    uint16_t getFrameCount() {
+        return _frameCount;
+    }
+    
+    void zeroFrames() {
+        if (!_frameBuffer) {
+            return;
+        }
+        for (uint16_t i = 0; i < _channelCount; ++i) {
+            std::memset(_frameBuffer[i], 0, sizeof(T)*_frameCountMax);
+        }
+    }
+     
+    template< typename S >
+    void copyFrames(uint16_t channelCount, const uint16_t frameCount, S* frames, const bool copyOut = false) {
+        if ( !_frameBuffer || !frames) {
+            return;
+        }
+        assert(channelCount == _channelCount);
+        assert(frameCount <= _frameCountMax);
+        
+        _frameCount = frameCount;  // we allow copying fewer frames than we've allocated
+        
+        if (copyOut) {
+            S* dst = frames;
+            
+            if(typeid(T) == typeid(S)) { // source and destination types are the same
+                for (int i = 0; i < _frameCount; ++i) {
+                    for (int j = 0; j < _channelCount; ++j) {
+                        *dst++ = _frameBuffer[j][i];
+                    }
+                }
+            }
+            else {
+                if(typeid(T) == typeid(float32_t) &&
+                   typeid(S) == typeid(int16_t)) {
+                    
+                    const int scale = (2 << ((8 * sizeof(S)) - 1));
+                    
+                    for (int i = 0; i < _frameCount; ++i) {
+                        for (int j = 0; j < _channelCount; ++j) {
+                            *dst++ = (S)(_frameBuffer[j][i] * scale);
+                        }
+                    }
+                }
+                else {
+                    assert(0); // currently unsupported conversion
+                }
+            }
+        }
+        else { // copyIn
+            S* src = frames;
+            
+            if(typeid(T) == typeid(S)) { // source and destination types are the same
+                for (int i = 0; i < _frameCount; ++i) {
+                    for (int j = 0; j < _channelCount; ++j) {
+                        _frameBuffer[j][i] = *src++;
+                    }
+                }
+            }
+            else {
+                if(typeid(T) == typeid(float32_t) &&
+                   typeid(S) == typeid(int16_t)) {
+                    
+                    const int scale = (2 << ((8 * sizeof(S)) - 1));
+                    
+                    for (int i = 0; i < _frameCount; ++i) {
+                        for (int j = 0; j < _channelCount; ++j) {
+                            _frameBuffer[j][i] = ((T)(*src++)) / scale;
+                        }
+                    }
+                }
+                else {
+                    assert(0); // currently unsupported conversion
+                }
+            }
+        }
+    }
+};
+
+typedef AudioFrameBuffer< float32_t > AudioBufferFloat32;
+typedef AudioFrameBuffer< int32_t > AudioBufferSInt32;
+
+#endif // hifi_AudioBuffer_h
+