diff --git a/examples/07-callback/callback.cpp b/examples/07-callback/callback.cpp
index 8bba8353..fd793a0e 100644
--- a/examples/07-callback/callback.cpp
+++ b/examples/07-callback/callback.cpp
@@ -10,6 +10,7 @@
 #include <bx/string.h>
 #include "../common/dbg.h"
 #include "../common/math.h"
+#include "../common/aviwriter.h"
 
 #include <inttypes.h>
 #include <stdio.h>
@@ -146,181 +147,6 @@ void saveTga(const char* _filePath, uint32_t _width, uint32_t _height, uint32_t
 	}
 }
 
-// Simple AVI writer. VideoLAN and VirtualDub can decode it.
-// Needs some bits to get jiggled to work with other players. But it's good
-// enough for an example.
-struct AviWriter
-{
-	AviWriter()
-		: m_frame(NULL)
-		, m_frameSize(0)
-		, m_width(0)
-		, m_height(0)
-		, m_yflip(false)
-	{
-	}
-
-	bool open(const char* _filePath, uint32_t _width, uint32_t _height, uint32_t _fps, bool _yflip)
-	{
-		if (0 != m_writer.open(_filePath) )
-		{
-			return false;
-		}
-
-		m_frameSize = _width * _height * 3;
-		m_frame = new uint8_t[m_frameSize + 8];
-		m_width = _width;
-		m_height = _height;
-		
-		// Bgfx returns _yflip true for OpenGL since bottom left corner is 0, 0. In D3D top left corner
-		// is 0, 0. DIB expect OpenGL style coordinates, so this is inverted logic for AVI writer.
-		m_yflip = !_yflip;
-
-		bx::StaticMemoryBlockWriter mem(m_frame, 8);
-		// Stream Data (LIST 'movi' Chunk) http://msdn.microsoft.com/en-us/library/ms899496.aspx
-		bx::write(&mem, BX_MAKEFOURCC('0', '0', 'd', 'b') );
-		bx::write(&mem, m_frameSize);
-
-		bx::write(&m_writer, BX_MAKEFOURCC('R', 'I', 'F', 'F') );
-		bx::write(&m_writer, UINT32_C(0) );
-
-		bx::write(&m_writer, BX_MAKEFOURCC('A', 'V', 'I', ' ') );
-
-		// AVI RIFF Form http://msdn.microsoft.com/en-us/library/ms899422.aspx
-		bx::write(&m_writer, BX_MAKEFOURCC('L', 'I', 'S', 'T') );
-		bx::write(&m_writer, UINT32_C(196) );
-		bx::write(&m_writer, BX_MAKEFOURCC('h', 'd', 'r', 'l') );
-
-		// AVI Main Header http://msdn.microsoft.com/en-us/library/ms779632.aspx
-		bx::write(&m_writer, BX_MAKEFOURCC('a', 'v', 'i', 'h') );
-		bx::write(&m_writer, UINT32_C(56) );
-		bx::write(&m_writer, UINT32_C(0) );      // dwMicroSecPerFrame
-		bx::write(&m_writer, UINT32_C(0) );      // dwMaxBytesPerSec
-		bx::write(&m_writer, UINT32_C(0) );      // dwPaddingGranularity
-		bx::write(&m_writer, UINT32_C(0) );      // dwFlags
-		bx::write(&m_writer, UINT32_C(0) );      // dwTotalFrames
-		bx::write(&m_writer, UINT32_C(0) );      // dwInitialFrames
-		bx::write(&m_writer, UINT32_C(1) );      // dwStreams
-		bx::write(&m_writer, UINT32_C(0) );      // dwSuggestedBufferSize
-		bx::write(&m_writer, _width);            // dwWidth
-		bx::write(&m_writer, _height);           // dwHeight
-		bx::write(&m_writer, UINT32_C(0) );      // dwReserved0
-		bx::write(&m_writer, UINT32_C(0) );      // dwReserved1
-		bx::write(&m_writer, UINT32_C(0) );      // dwReserved2
-		bx::write(&m_writer, UINT32_C(0) );      // dwReserved3
-
-		bx::write(&m_writer, BX_MAKEFOURCC('L', 'I', 'S', 'T') );
-		bx::write(&m_writer, UINT32_C(120) );
-		bx::write(&m_writer, BX_MAKEFOURCC('s', 't', 'r', 'l') );
-
-		// AVISTREAMHEADER Structure http://msdn.microsoft.com/en-us/library/ms779638.aspx
-		bx::write(&m_writer, BX_MAKEFOURCC('s', 't', 'r', 'h') );
-		bx::write(&m_writer, UINT32_C(56) );
-		// AVI Stream Headers http://msdn.microsoft.com/en-us/library/ms899423.aspx
-		bx::write(&m_writer, BX_MAKEFOURCC('v', 'i', 'd', 's') ); // fccType
-		bx::write(&m_writer, BX_MAKEFOURCC('D', 'I', 'B', ' ') ); // fccHandler
-		bx::write(&m_writer, UINT32_C(0) );      // dwFlags
-		bx::write(&m_writer, UINT16_C(0) );      // wPriority
-		bx::write(&m_writer, UINT16_C(0) );      // wLanguage
-		bx::write(&m_writer, UINT32_C(0) );      // dwInitialFrames
-		bx::write(&m_writer, UINT32_C(1000) );   // dwScale
-		bx::write(&m_writer, 1000*_fps);         // dwRate
-		bx::write(&m_writer, UINT32_C(0) );      // dwStart
-		bx::write(&m_writer, UINT32_C(0) );      // dwLength
-		bx::write(&m_writer, UINT32_C(0) );      // dwSuggestedBufferSize
-		bx::write(&m_writer, UINT32_C(0) );      // dwQuality
-		bx::write(&m_writer, UINT32_C(0) );      // dwSampleSize
-		bx::write(&m_writer, INT16_C(0) );       // rcFrame.left
-		bx::write(&m_writer, INT16_C(0) );       // rcFrame.top
-		bx::write(&m_writer, INT16_C(0) );       // rcFrame.right
-		bx::write(&m_writer, INT16_C(0) );       // rcFrame.bottom
-
-		bx::write(&m_writer, BX_MAKEFOURCC('s', 't', 'r', 'f') );
-		bx::write(&m_writer, UINT32_C(44) );
-
-		// BITMAPINFOHEADER structure http://msdn.microsoft.com/en-us/library/windows/desktop/dd318229%28v=vs.85%29.aspx
-		bx::write(&m_writer, UINT32_C(40) );     // biSize
-		bx::write(&m_writer, _width);            // biWidth
-		bx::write(&m_writer, _height);           // biHeight
-		bx::write(&m_writer, UINT16_C(1) );      // biPlanes
-		bx::write(&m_writer, UINT16_C(24) );     // biBitCount
-		bx::write(&m_writer, UINT32_C(0) );      // biCompression
-		bx::write(&m_writer, UINT32_C(0) );      // biSizeImage
-		bx::write(&m_writer, UINT32_C(0) );      // biXPelsPerMeter
-		bx::write(&m_writer, UINT32_C(0) );      // biYPelsPerMeter
-		bx::write(&m_writer, UINT32_C(0) );      // biClrUsed
-		bx::write(&m_writer, UINT32_C(0) );      // biClrImportant
-		bx::write(&m_writer, UINT32_C(0) );
-
-		bx::write(&m_writer, BX_MAKEFOURCC('L', 'I', 'S', 'T') );
-		bx::write(&m_writer, UINT32_C(0) );
-		bx::write(&m_writer, BX_MAKEFOURCC('m', 'o', 'v', 'i') );
-
-		return true;
-	}
-
-	void close()
-	{
-		if (NULL != m_frame)
-		{
-			m_writer.close();
-
-			delete [] m_frame;
-			m_frame = NULL;
-			m_frameSize = 0;
-		}
-	}
-
-	void frame(const void* _data)
-	{
-		if (NULL != m_frame)
-		{
-			uint32_t width = m_width;
-			uint32_t height = m_height;
-
-			uint8_t* bgr = &m_frame[8];
-
-			if (m_yflip)
-			{
-				for (uint32_t yy = 0; yy < height; ++yy)
-				{
-					const uint8_t* bgra = (const uint8_t*)_data + (height-1-yy)*width*4;
-
-					for (uint32_t ii = 0; ii < width; ++ii)
-					{
-						bgr[0] = bgra[0];
-						bgr[1] = bgra[1];
-						bgr[2] = bgra[2];
-						bgr += 3;
-						bgra += 4;
-					}
-				}
-			}
-			else
-			{
-				const uint8_t* bgra = (const uint8_t*)_data;
-				for (uint32_t ii = 0, num = m_frameSize/3; ii < num; ++ii)
-				{
-					bgr[0] = bgra[0];
-					bgr[1] = bgra[1];
-					bgr[2] = bgra[2];
-					bgr += 3;
-					bgra += 4;
-				}
-			}
-
-			bx::write(&m_writer, m_frame, m_frameSize+8);
-		}
-	}
-
-	bx::CrtFileWriter m_writer;
-	uint8_t* m_frame;
-	uint32_t m_frameSize;
-	uint32_t m_width;
-	uint32_t m_height;
-	bool m_yflip;
-};
-
 struct BgfxCallback : public bgfx::CallbackI
 {
 	virtual ~BgfxCallback()
diff --git a/examples/common/aviwriter.h b/examples/common/aviwriter.h
new file mode 100644
index 00000000..a19d8af2
--- /dev/null
+++ b/examples/common/aviwriter.h
@@ -0,0 +1,186 @@
+/*
+ * Copyright 2011-2012 Branimir Karadzic. All rights reserved.
+ * License: http://www.opensource.org/licenses/BSD-2-Clause
+ */
+
+#ifndef __AVIWRITER_H__
+#define __AVIWRITER_H__
+
+#include <bx/readerwriter.h>
+
+// Simple AVI writer. VideoLAN and VirtualDub can decode it.
+// Needs some bits to get jiggled to work with other players. But it's good
+// enough for an example.
+struct AviWriter
+{
+	AviWriter()
+		: m_frame(NULL)
+		, m_frameSize(0)
+		, m_width(0)
+		, m_height(0)
+		, m_yflip(false)
+	{
+	}
+
+	bool open(const char* _filePath, uint32_t _width, uint32_t _height, uint32_t _fps, bool _yflip)
+	{
+		if (0 != m_writer.open(_filePath) )
+		{
+			return false;
+		}
+
+		m_frameSize = _width * _height * 3;
+		m_frame = new uint8_t[m_frameSize + 8];
+		m_width = _width;
+		m_height = _height;
+		
+		// Bgfx returns _yflip true for OpenGL since bottom left corner is 0, 0. In D3D top left corner
+		// is 0, 0. DIB expect OpenGL style coordinates, so this is inverted logic for AVI writer.
+		m_yflip = !_yflip;
+
+		bx::StaticMemoryBlockWriter mem(m_frame, 8);
+		// Stream Data (LIST 'movi' Chunk) http://msdn.microsoft.com/en-us/library/ms899496.aspx
+		bx::write(&mem, BX_MAKEFOURCC('0', '0', 'd', 'b') );
+		bx::write(&mem, m_frameSize);
+
+		bx::write(&m_writer, BX_MAKEFOURCC('R', 'I', 'F', 'F') );
+		bx::write(&m_writer, UINT32_C(0) );
+
+		bx::write(&m_writer, BX_MAKEFOURCC('A', 'V', 'I', ' ') );
+
+		// AVI RIFF Form http://msdn.microsoft.com/en-us/library/ms899422.aspx
+		bx::write(&m_writer, BX_MAKEFOURCC('L', 'I', 'S', 'T') );
+		bx::write(&m_writer, UINT32_C(196) );
+		bx::write(&m_writer, BX_MAKEFOURCC('h', 'd', 'r', 'l') );
+
+		// AVI Main Header http://msdn.microsoft.com/en-us/library/ms779632.aspx
+		bx::write(&m_writer, BX_MAKEFOURCC('a', 'v', 'i', 'h') );
+		bx::write(&m_writer, UINT32_C(56) );
+		bx::write(&m_writer, UINT32_C(0) );      // dwMicroSecPerFrame
+		bx::write(&m_writer, UINT32_C(0) );      // dwMaxBytesPerSec
+		bx::write(&m_writer, UINT32_C(0) );      // dwPaddingGranularity
+		bx::write(&m_writer, UINT32_C(0) );      // dwFlags
+		bx::write(&m_writer, UINT32_C(0) );      // dwTotalFrames
+		bx::write(&m_writer, UINT32_C(0) );      // dwInitialFrames
+		bx::write(&m_writer, UINT32_C(1) );      // dwStreams
+		bx::write(&m_writer, UINT32_C(0) );      // dwSuggestedBufferSize
+		bx::write(&m_writer, _width);            // dwWidth
+		bx::write(&m_writer, _height);           // dwHeight
+		bx::write(&m_writer, UINT32_C(0) );      // dwReserved0
+		bx::write(&m_writer, UINT32_C(0) );      // dwReserved1
+		bx::write(&m_writer, UINT32_C(0) );      // dwReserved2
+		bx::write(&m_writer, UINT32_C(0) );      // dwReserved3
+
+		bx::write(&m_writer, BX_MAKEFOURCC('L', 'I', 'S', 'T') );
+		bx::write(&m_writer, UINT32_C(120) );
+		bx::write(&m_writer, BX_MAKEFOURCC('s', 't', 'r', 'l') );
+
+		// AVISTREAMHEADER Structure http://msdn.microsoft.com/en-us/library/ms779638.aspx
+		bx::write(&m_writer, BX_MAKEFOURCC('s', 't', 'r', 'h') );
+		bx::write(&m_writer, UINT32_C(56) );
+		// AVI Stream Headers http://msdn.microsoft.com/en-us/library/ms899423.aspx
+		bx::write(&m_writer, BX_MAKEFOURCC('v', 'i', 'd', 's') ); // fccType
+		bx::write(&m_writer, BX_MAKEFOURCC('D', 'I', 'B', ' ') ); // fccHandler
+		bx::write(&m_writer, UINT32_C(0) );      // dwFlags
+		bx::write(&m_writer, UINT16_C(0) );      // wPriority
+		bx::write(&m_writer, UINT16_C(0) );      // wLanguage
+		bx::write(&m_writer, UINT32_C(0) );      // dwInitialFrames
+		bx::write(&m_writer, UINT32_C(1000) );   // dwScale
+		bx::write(&m_writer, 1000*_fps);         // dwRate
+		bx::write(&m_writer, UINT32_C(0) );      // dwStart
+		bx::write(&m_writer, UINT32_C(0) );      // dwLength
+		bx::write(&m_writer, UINT32_C(0) );      // dwSuggestedBufferSize
+		bx::write(&m_writer, UINT32_C(0) );      // dwQuality
+		bx::write(&m_writer, UINT32_C(0) );      // dwSampleSize
+		bx::write(&m_writer, INT16_C(0) );       // rcFrame.left
+		bx::write(&m_writer, INT16_C(0) );       // rcFrame.top
+		bx::write(&m_writer, INT16_C(0) );       // rcFrame.right
+		bx::write(&m_writer, INT16_C(0) );       // rcFrame.bottom
+
+		bx::write(&m_writer, BX_MAKEFOURCC('s', 't', 'r', 'f') );
+		bx::write(&m_writer, UINT32_C(44) );
+
+		// BITMAPINFOHEADER structure http://msdn.microsoft.com/en-us/library/windows/desktop/dd318229%28v=vs.85%29.aspx
+		bx::write(&m_writer, UINT32_C(40) );     // biSize
+		bx::write(&m_writer, _width);            // biWidth
+		bx::write(&m_writer, _height);           // biHeight
+		bx::write(&m_writer, UINT16_C(1) );      // biPlanes
+		bx::write(&m_writer, UINT16_C(24) );     // biBitCount
+		bx::write(&m_writer, UINT32_C(0) );      // biCompression
+		bx::write(&m_writer, UINT32_C(0) );      // biSizeImage
+		bx::write(&m_writer, UINT32_C(0) );      // biXPelsPerMeter
+		bx::write(&m_writer, UINT32_C(0) );      // biYPelsPerMeter
+		bx::write(&m_writer, UINT32_C(0) );      // biClrUsed
+		bx::write(&m_writer, UINT32_C(0) );      // biClrImportant
+		bx::write(&m_writer, UINT32_C(0) );
+
+		bx::write(&m_writer, BX_MAKEFOURCC('L', 'I', 'S', 'T') );
+		bx::write(&m_writer, UINT32_C(0) );
+		bx::write(&m_writer, BX_MAKEFOURCC('m', 'o', 'v', 'i') );
+
+		return true;
+	}
+
+	void close()
+	{
+		if (NULL != m_frame)
+		{
+			m_writer.close();
+
+			delete [] m_frame;
+			m_frame = NULL;
+			m_frameSize = 0;
+		}
+	}
+
+	void frame(const void* _data)
+	{
+		if (NULL != m_frame)
+		{
+			uint32_t width = m_width;
+			uint32_t height = m_height;
+
+			uint8_t* bgr = &m_frame[8];
+
+			if (m_yflip)
+			{
+				for (uint32_t yy = 0; yy < height; ++yy)
+				{
+					const uint8_t* bgra = (const uint8_t*)_data + (height-1-yy)*width*4;
+
+					for (uint32_t ii = 0; ii < width; ++ii)
+					{
+						bgr[0] = bgra[0];
+						bgr[1] = bgra[1];
+						bgr[2] = bgra[2];
+						bgr += 3;
+						bgra += 4;
+					}
+				}
+			}
+			else
+			{
+				const uint8_t* bgra = (const uint8_t*)_data;
+				for (uint32_t ii = 0, num = m_frameSize/3; ii < num; ++ii)
+				{
+					bgr[0] = bgra[0];
+					bgr[1] = bgra[1];
+					bgr[2] = bgra[2];
+					bgr += 3;
+					bgra += 4;
+				}
+			}
+
+			bx::write(&m_writer, m_frame, m_frameSize+8);
+		}
+	}
+
+	bx::CrtFileWriter m_writer;
+	uint8_t* m_frame;
+	uint32_t m_frameSize;
+	uint32_t m_width;
+	uint32_t m_height;
+	bool m_yflip;
+};
+
+#endif // __AVIWRITER_H__