#include "stdafx.h"
#include "ImageCompress.h"

ULONG_PTR ImageCompress::m_gdiplusToken = NULL;

ImageCompress::ImageCompress(void)
{
}

ImageCompress::~ImageCompress(void)
{
}

// 图片压缩格式;
//image/bmp
//image/jpeg
//image/gif
//image/tiff
//image/png
int ImageCompress::GetEncoderClsid(IN const WCHAR* format, OUT CLSID* pClsid)
{
	UINT  nNumberOfImageEncoders = 0;          // number of image encoders
	UINT  nSizeOfImageEndcoderArray = 0;         // size of the image encoder array in bytes

	ImageCodecInfo* pImageCodecInfo = NULL;

	GetImageEncodersSize(&nNumberOfImageEncoders, &nSizeOfImageEndcoderArray);
	if (nSizeOfImageEndcoderArray == 0)
		return -1;  // Failure

	pImageCodecInfo = (ImageCodecInfo*)(malloc(nSizeOfImageEndcoderArray));
	if (pImageCodecInfo == NULL)
		return -1;  // Failure

	GetImageEncoders(nNumberOfImageEncoders, nSizeOfImageEndcoderArray, pImageCodecInfo);

	for (UINT i = 0; i < nNumberOfImageEncoders; ++i)
	{
		if (wcscmp(pImageCodecInfo[i].MimeType, format) == 0)
		{
			*pClsid = pImageCodecInfo[i].Clsid;
			free(pImageCodecInfo);
			return i;  // Success
		}
	}
	free(pImageCodecInfo);
	return -1;  // FailureFailure
}

//Scale 比例;
//Zoom 缩放;
// 给定最小（最大）宽度,按比例（原图宽/指定宽）缩放图片大小，获取完整缩放尺寸;
//-----------------------------------------------------------------------------------------------------------------------
//
// 函数：ScaleZoombySpecificWidth
// 描述：以指定高来缩放矩形;
// 参数：
//		nWidth			: 指定的压缩宽;
//		nHeight			: 指定的压缩高;
//		rc				: 压缩存放的区域;
//
// 返回：#;
//
// 注意：;
//
//-----------------------------------------------------------------------------------------------------------------------
void ImageCompress::ScaleZoombySpecificHeight(IN const int &nWidth, IN const int &nHeight, IN OUT CRect &rc)
{
	try
	{
		if (nWidth == 0 || nHeight == 0)return;

		// 图片长宽比例;
		float fscale = (float)nWidth / (float)nHeight;

		// 设备长宽比例;
		float rcscale = ((float)rc.Width()) / ((float)rc.Height());

		int rcwid = rc.Width();
		int rchei = rc.Height();
		int dt = 0;

		// Jeff.如果设备长宽比例 <  图片长宽比例;(即相同长度下,高越大比例值越小,所以此时图片尺寸 与 显示设备的尺寸相比,要显得更长)
		if (rcscale < fscale)
		{
			// Jeff.remarks
			// 调整显示设备的大小,以使之能容纳图片尺寸;(即长宽比例上,要大于或等于图片的长宽比例)
			// 所以有两种方法使得 rcscale >= fscale 表达式成立：
			// -----------------------------------------------
			// 方法1：显示设备宽加x值,计算出下面表达式x的值即可
			// (rc.Width()+x) / rc.Height() >= width/height;
			// 方法2：显示设备高减x值,计算出下面表达式x的值即可
			// (rc.Width()) / (rc.Height()-x) >= width/height;
			//------------------------------------------------
			// 两种方法的最后表达式为：
			// x >= rc.Height() - rcWidth()*(height/width);
			// 即 x >= rc.Height() - rcWidth()/fscale;
			//------------------------------------------------
			dt = (rchei - rcwid / fscale) / 2;
			rc.top += dt;
			rc.bottom -= dt;
		}
		else
		{
			dt = (rcwid - rchei*fscale) / 2;
			rc.left += dt;
			rc.right -= dt;
		}
	}
	catch (...)
	{
	}
}

//-----------------------------------------------------------------------------------------------------------------------
//
// 函数：ScaleZoombySpecificWidth
// 描述：以指定宽来缩放矩形;
// 参数：
//		nWidth			: 指定的压缩宽;
//		nHeight			: 指定的压缩高;
//		rc				: 压缩存放的区域;
//
// 返回：#;
//
// 注意：;
//
//-----------------------------------------------------------------------------------------------------------------------
void ImageCompress::ScaleZoombySpecificWidth(IN const int &nWidth, IN const int &nHeight, IN OUT CRect &rc)
{
	try
	{
		if (nWidth == 0 || nHeight == 0)return;

		// 图片长宽比例;
		float fscale = (float)nWidth / (float)nHeight;

		// 设备长宽比例;
		float rcscale = ((float)rc.Width()) / ((float)rc.Height());

		int rcwid = rc.Width();
		int rchei = rc.Height();
		int dt = 0;

		// Jeff.如果设备长宽比例 <  图片长宽比例;(即相同长度下,高越大比例值越小,所以此时图片尺寸 与 显示设备的尺寸相比,要显得更长)
		if (rcscale < fscale)
		{
			// Jeff.remarks
			// 调整显示设备的大小,以使之能容纳图片尺寸;(即长宽比例上,要大于或等于图片的长宽比例)
			// 所以有两种方法使得 rcscale >= fscale 表达式成立：
			// -----------------------------------------------
			// 方法1：显示设备宽加x值,计算出下面表达式x的值即可
			// (rc.Width()+x) / rc.Height() >= width/height;
			// 方法2：显示设备高减x值,计算出下面表达式x的值即可
			// (rc.Width()) / (rc.Height()-x) >= width/height;
			//------------------------------------------------
			// 两种方法的最后表达式为：
			// x >= rc.Height() - rcWidth()*(height/width);
			// 即 x >= rc.Height() - rcWidth()/fscale;
			//------------------------------------------------
			dt = (rcwid - rchei*fscale) / 2;
			rc.left += dt;
			rc.right -= dt;
		}
		else
		{
			dt = (rchei - rcwid / fscale) / 2;
			rc.top += dt;
			rc.bottom -= dt;
		}
	}
	catch (...)
	{
	}
}

//-----------------------------------------------------------------------------------------------------------------------
//
// 函数：SaveImageToFile
// 描述：压缩指定目录的相片到指定目录;
// 参数：
//		img			: Image对象;
//		path		: 压缩后相片保存路径;
//		quality		: 压缩的质量值;
//
// 返回：#;
//
// 注意：;
//
//-----------------------------------------------------------------------------------------------------------------------
void ImageCompress::SaveImageToFile(IN Image *img, IN CString &path, IN ULONG quality)
{
	try
	{
		if (img == NULL)return;
		CLSID   encoderClsid;
		BSTR bstr = path.AllocSysString();
		path.MakeLower();
		if (path.Right(3) == _T("bmp"))
		{
			GetEncoderClsid(L"image/bmp", &encoderClsid);
			img->Save(bstr, &encoderClsid, NULL);
		}
		else if (path.Right(3) == _T("png"))
		{
			GetEncoderClsid(L"image/png", &encoderClsid);
			img->Save(bstr, &encoderClsid, NULL);
		}
		else// if(path.Right (3)== _T("jpg"))
		{
			GetEncoderClsid(L"image/jpeg", &encoderClsid);
			EncoderParameters encoderParameters;
			encoderParameters.Count = 1;
			encoderParameters.Parameter[0].Guid = EncoderQuality;
			encoderParameters.Parameter[0].Type = EncoderParameterValueTypeLong;
			encoderParameters.Parameter[0].NumberOfValues = 1;
			// Save the image as a JPEG with quality level 100.
			encoderParameters.Parameter[0].Value = &quality;
			img->Save(bstr, &encoderClsid, &encoderParameters);
		}
		SysFreeString(bstr);
	}
	catch (...)
	{
	}
}

//-----------------------------------------------------------------------------------------------------------------------
//
// 函数：ToCompressImage
// 描述：压缩指定目录的相片到指定目录;
// 参数：
//		pImageSource	: 原相片完整路径;
//		pImageDest		: 压缩后相片保存路径;
//		nXPiexel		: 压缩的像素宽;
//		nYPiexel		: 压缩的像素高;
//
// 返回：#;
//
// 注意：;
//
//-----------------------------------------------------------------------------------------------------------------------
BOOL ImageCompress::ToCompressImage(IN const TCHAR *pImageSource, IN const TCHAR *pImageDest, IN const int &nXPiexel, IN const int &nYPiexel)
{
	Image *pImage = NULL;

	::DeleteFile(pImageDest);

	// 1.从文件中以读的方式加载图片到Image中;
	CFile cf;
	if (cf.Open(pImageSource, CFile::modeRead))
	{
		DWORD dwLength = cf.GetLength();
		BYTE *pData = new BYTE[dwLength];

		if (pData == NULL)// 创建内存失败;
			return FALSE;

		cf.Read(pData, dwLength);
		cf.Close();

		// 1.1.将文件数据加载到内存数据中;
		HGLOBAL taghMem = GlobalAlloc(GMEM_MOVEABLE, dwLength);
		if (taghMem == NULL) // 创建内存失败;
			return FALSE;

		BYTE *pMem = (BYTE*)GlobalLock(taghMem);
		memcpy(pMem, pData, dwLength);

		// 1.2.创建二进制流对象;
		IStream *pStream;
		CreateStreamOnHGlobal(taghMem, TRUE, &pStream);
		pImage = Gdiplus::Image::FromStream(pStream);

		GlobalUnlock(taghMem);
		pStream->Release();

		delete[]pData;
	}

	// 2.加载后……
	if (pImage == NULL)	// 加载失败;
		return FALSE;

	// 2.1.当图片的像素大于要设定的像素时,进行处理;
	if (pImage->GetWidth() > nXPiexel || pImage->GetHeight() > nYPiexel)
	{
		CRect tagRect(0, 0, nXPiexel, nYPiexel);
		ScaleZoombySpecificWidth(pImage->GetWidth(), pImage->GetHeight(), tagRect);

		Bitmap bp(tagRect.Width(), tagRect.Height());
		Graphics *graphic = Graphics::FromImage(&bp);
		graphic->Clear(Color(255, 255, 255, 255));

		graphic->SetInterpolationMode(InterpolationModeHighQualityBicubic);
		graphic->SetSmoothingMode(SmoothingModeHighQuality);//SmoothingModeHighSpeed
		graphic->SetPixelOffsetMode(PixelOffsetModeHighQuality);
		graphic->SetCompositingMode(CompositingModeSourceOver);
		graphic->SetCompositingQuality(CompositingQualityHighQuality);
		graphic->SetTextRenderingHint(TextRenderingHintAntiAliasGridFit);
		graphic->DrawImage(pImage, RectF(0, 0, tagRect.Width(), tagRect.Height()), 0, 0, pImage->GetWidth(), pImage->GetHeight(), UnitPixel);

		delete pImage;

		try
		{
			CString path(pImageDest);

			CLSID   encoderClsid;
			BSTR bstr = path.AllocSysString();
			path.MakeLower();
			if (path.Right(3) == _T("bmp"))
			{
				GetEncoderClsid(L"image/bmp", &encoderClsid);
				bp.Save(bstr, &encoderClsid, NULL);
			}
			else if (path.Right(3) == _T("png"))
			{
				GetEncoderClsid(L"image/png", &encoderClsid);
				bp.Save(bstr, &encoderClsid, NULL);
			}
			else// if(path.Right (3)=="jpg")
			{
				ULONG quality = 95;
				GetEncoderClsid(L"image/jpeg", &encoderClsid);
				EncoderParameters encoderParameters;
				encoderParameters.Count = 1;
				encoderParameters.Parameter[0].Guid = EncoderQuality;
				encoderParameters.Parameter[0].Type = EncoderParameterValueTypeLong;
				encoderParameters.Parameter[0].NumberOfValues = 1;
				// Save the image as a JPEG with quality level 100.
				encoderParameters.Parameter[0].Value = &quality;
				bp.Save(bstr, &encoderClsid, &encoderParameters);
			}
			SysFreeString(bstr);
		}
		catch (...)
		{
			return FALSE;
		}
	}

	return  TRUE;
}