C#图像缩放与裁剪

文笔不好，不废话，直接进入正题，不解释，相信大家都看得懂。

 

按百分比缩放图像：

public static Image ScaleByPercent(Image imgPhoto, int Percent){    float nPercent = ((float)Percent/100);    int sourceWidth = imgPhoto.Width;    int sourceHeight = imgPhoto.Height;    int sourceX = 0;    int sourceY = 0;    int destX = 0;    int destY = 0;     int destWidth  = (int)(sourceWidth * nPercent);    int destHeight = (int)(sourceHeight * nPercent);    Bitmap bmPhoto = new Bitmap(destWidth, destHeight,                              PixelFormat.Format24bppRgb);    bmPhoto.SetResolution(imgPhoto.HorizontalResolution,                             imgPhoto.VerticalResolution);    Graphics grPhoto = Graphics.FromImage(bmPhoto);    grPhoto.InterpolationMode = InterpolationMode.HighQualityBicubic;    grPhoto.DrawImage(imgPhoto,         new Rectangle(destX,destY,destWidth,destHeight),        new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight),        GraphicsUnit.Pixel);    grPhoto.Dispose();    return bmPhoto;}

按指定大小缩放图像：

public static Image FixedSize(Image imgPhoto, int Width, int Height){    int sourceWidth = imgPhoto.Width;    int sourceHeight = imgPhoto.Height;    int sourceX = 0;    int sourceY = 0;    int destX = 0;    int destY = 0;     float nPercent = 0;    float nPercentW = 0;    float nPercentH = 0;    nPercentW = ((float)Width/(float)sourceWidth);    nPercentH = ((float)Height/(float)sourceHeight);    if(nPercentH < nPercentW)    {        nPercent = nPercentH;        destX = System.Convert.ToInt16((Width -                       (sourceWidth * nPercent))/2);    }    else    {        nPercent = nPercentW;        destY = System.Convert.ToInt16((Height -                       (sourceHeight * nPercent))/2);    }    int destWidth  = (int)(sourceWidth * nPercent);    int destHeight = (int)(sourceHeight * nPercent);    Bitmap bmPhoto = new Bitmap(Width, Height,                       PixelFormat.Format24bppRgb);    bmPhoto.SetResolution(imgPhoto.HorizontalResolution,                      imgPhoto.VerticalResolution);    Graphics grPhoto = Graphics.FromImage(bmPhoto);    grPhoto.Clear(Color.Red);    grPhoto.InterpolationMode =             InterpolationMode.HighQualityBicubic;    grPhoto.DrawImage(imgPhoto,         new Rectangle(destX,destY,destWidth,destHeight),        new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight),        GraphicsUnit.Pixel);    grPhoto.Dispose();    return bmPhoto;}

按指定位置裁剪指定大小图像：

public static Image Crop(Image imgPhoto, int Width,                     int Height, AnchorPosition Anchor){    int sourceWidth = imgPhoto.Width;    int sourceHeight = imgPhoto.Height;    int sourceX = 0;    int sourceY = 0;    int destX = 0;    int destY = 0;    float nPercent = 0;    float nPercentW = 0;    float nPercentH = 0;    nPercentW = ((float)Width/(float)sourceWidth);    nPercentH = ((float)Height/(float)sourceHeight);    if(nPercentH < nPercentW)    {        nPercent = nPercentW;        switch(Anchor)        {            case AnchorPosition.Top:                destY = 0;                break;            case AnchorPosition.Bottom:                destY = (int)                    (Height - (sourceHeight * nPercent));                    break;            default:                destY = (int)                    ((Height - (sourceHeight * nPercent))/2);                break;        }    }    else    {        nPercent = nPercentH;        switch(Anchor)        {            case AnchorPosition.Left:                destX = 0;                break;            case AnchorPosition.Right:                destX = (int)                  (Width - (sourceWidth * nPercent));                break;            default:                destX = (int)                  ((Width - (sourceWidth * nPercent))/2);                break;        }     }    int destWidth  = (int)(sourceWidth * nPercent);    int destHeight = (int)(sourceHeight * nPercent);    Bitmap bmPhoto = new Bitmap(Width,             Height, PixelFormat.Format24bppRgb);    bmPhoto.SetResolution(imgPhoto.HorizontalResolution,             imgPhoto.VerticalResolution);    Graphics grPhoto = Graphics.FromImage(bmPhoto);    grPhoto.InterpolationMode =             InterpolationMode.HighQualityBicubic;    grPhoto.DrawImage(imgPhoto,         new Rectangle(destX,destY,destWidth,destHeight),        new Rectangle(sourceX,sourceY,sourceWidth,sourceHeight),        GraphicsUnit.Pixel);    grPhoto.Dispose();    return bmPhoto;}

 

 

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http://blog.csdn.net/stuqbx