C# 图片裁剪

C# 图片裁剪

分类： c# DataBase 2010-01-14 15:56  1559人阅读  评论(3)  收藏  举报

c# codec input string image null

 

/// <summary>
/// 缩小裁剪图片
/// </summary>
/// <param name="int_Width">要缩小裁剪图片宽度</param>
/// <param name="int_Height">要缩小裁剪图片长度</param>
/// <param name="input_ImgUrl">要处理图片路径</param>
/// <param name="out_ImgUrl">处理完毕图片路径</param>
public void ImgReduceCutOut(int int_Width, int int_Height, string input_ImgUrl, string out_ImgUrl)
{
    // ＝＝＝上传标准图大小＝＝＝
    int int_Standard_Width = 160;
    int int_Standard_Height = 160;

    int Reduce_Width = 0; // 缩小的宽度
    int Reduce_Height = 0; // 缩小的高度
    int CutOut_Width = 0; // 裁剪的宽度
    int CutOut_Height = 0; // 裁剪的高度
    int level = 100; //缩略图的质量 1-100的范围

    // ＝＝＝获得缩小，裁剪大小＝＝＝
    if (int_Standard_Height * int_Width / int_Standard_Width > int_Height)
    {
        Reduce_Width = int_Width;
        Reduce_Height = int_Standard_Height * int_Width / int_Standard_Width;
        CutOut_Width = int_Width;
        CutOut_Height = int_Height;
    }
    else if (int_Standard_Height * int_Width / int_Standard_Width < int_Height)
    {
        Reduce_Width = int_Standard_Width * int_Height / int_Standard_Height;
        Reduce_Height = int_Height;
        CutOut_Width = int_Width;
        CutOut_Height = int_Height;
    }
    else
    {
        Reduce_Width = int_Width;
        Reduce_Height = int_Height;
        CutOut_Width = int_Width;
        CutOut_Height = int_Height;
    }

    // ＝＝＝通过连接创建Image对象＝＝＝
    System.Drawing.Image oldimage = System.Drawing.Image.FromFile(Server.MapPath(input_ImgUrl));

    // ＝＝＝缩小图片＝＝＝
    System.Drawing.Image thumbnailImage = oldimage.GetThumbnailImage(Reduce_Width, Reduce_Height, new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback), IntPtr.Zero);
    Bitmap bm = new Bitmap(thumbnailImage);

    // ＝＝＝处理JPG质量的函数＝＝＝
    ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
    ImageCodecInfo ici = null;
    foreach (ImageCodecInfo codec in codecs)
    {
        if (codec.MimeType == "image/jpeg")
            ici = codec;
    }
    EncoderParameters ep = new EncoderParameters();
    ep.Param[0] = new EncoderParameter(Encoder.Quality, (long)level);

    //bm.Save(Server.MapPath("2.jpg"), ici, ep);

    // ＝＝＝裁剪图片＝＝＝
    Rectangle cloneRect = new Rectangle(0, 0, CutOut_Width, CutOut_Height);
    PixelFormat format = bm.PixelFormat;
    Bitmap cloneBitmap = bm.Clone(cloneRect, format);

    // ＝＝＝保存图片＝＝＝
    cloneBitmap.Save(Server.MapPath(out_ImgUrl), ici, ep);
}