C#在图像或位图中裁剪圆圈

时间:2011-04-20 18:10:08

标签: c# image bitmap

我确信它很容易,但似乎找不到任何有答案的人。 我有一个图像,我需要从该图像中切出一个圆或甚至其他形状。我需要这个代码在.net c#中。我在课堂上这样做,所以它不是wpf或winform。 我需要传递x和y pos以及圆的大小。

其他选项是AForge,ImageStatistics。我需要得到一个圆圈(图像的一部分)并获得StdDev。

感谢您的帮助。 安德鲁

- 更新为chris post。

这是c#中的chris帖子。不像他那么干净,但却是一个开始。

 public System.Drawing.Image x(string sourceFile, int circleUpperLeftX, int circleUpperLeftY, int circleDiameter)
    {
        Bitmap SourceImage = new Bitmap(System.Drawing.Image.FromFile(sourceFile));
        Rectangle CropRect = new Rectangle(circleUpperLeftX, circleUpperLeftY, circleDiameter, circleDiameter);
        Bitmap CroppedImage = SourceImage.Clone(CropRect, SourceImage.PixelFormat);
        TextureBrush TB = new TextureBrush(CroppedImage);
        Bitmap FinalImage = new Bitmap(circleDiameter, circleDiameter);
        Graphics G = Graphics.FromImage(FinalImage);
        G.FillEllipse(TB, 0, 0, circleDiameter, circleDiameter);
        return FinalImage;
    }

4 个答案:

答案 0 :(得分:5)

您可以使用TextureBrush。下面的代码将图像裁剪为正方形,然后将其加载到纹理画笔中,最后使用该画笔绘制椭圆/圆形:

Private Shared Function CropImageToCircle(ByVal sourceFile As String, ByVal circleUpperLeftX As Integer, ByVal circleUpperLeftY As Integer, ByVal circleDiameter As Integer) As Image
    ''//Load our source image
    Using SourceImage As New Bitmap(Image.FromFile(sourceFile))
        ''//Create a rectangle that crops a square of our image
        Dim CropRect As New Rectangle(circleUpperLeftX, circleUpperLeftY, circleDiameter, circleDiameter)
        ''//Crop the image to that square
        Using CroppedImage = SourceImage.Clone(CropRect, SourceImage.PixelFormat)
            ''//Create a texturebrush to draw our circle with
            Using TB As New TextureBrush(CroppedImage)
                ''//Create our output image
                Dim FinalImage As New Bitmap(circleDiameter, circleDiameter)
                ''//Create a graphics object to draw with
                Using G = Graphics.FromImage(FinalImage)
                    ''//Draw our cropped image onto the output image as an ellipse with the same width/height (circle)
                    G.FillEllipse(TB, 0, 0, circleDiameter, circleDiameter)
                    Return FinalImage
                End Using
            End Using
        End Using
    End Using
End Function

答案 1 :(得分:3)

制作一个与原始尺寸和像素格式相匹配的新Bitmap。 从新的位图创建图形。 将图形剪辑设置为新圆。 将原始图像绘制到新图形上。

public Bitmap ClipToCircle(Bitmap original, PointF center, float radius)
{
    Bitmap copy = new Bitmap(original);
    using (Graphics g = Graphics.FromImage(copy)) {
        RectangleF r = new RectangleF(center.X - radius, center.Y - radius, radius * 2, radius * 2);
        GraphicsPath path = new GraphicsPath();
        path.AddEllipse(r);
        g.Clip = new Region(path);
        g.DrawImage(original, 0, 0);
        return copy;
    }
}

答案 2 :(得分:0)

See this。您需要调用GDI +类(在C#中没有问题)来获得所需的功能。

答案 3 :(得分:0)

此代码可能对您有帮助 Screenshot

类代码:

@property
def getusernametextbox(self):
    return Browser.webDriverWait.until(ec.visibility_of_element_located((By.ID, "login_email")))

@property
def getpasswordtextbox(self):
    return Browser.webDriverWait.until(ec.visibility_of_element_located((By.CSS_SELECTOR, "tr[id=mockpass] input")))

@property
def getloginbutton(self):
    return Browser.webDriverWait.until(ec.element_to_be_clickable((By.NAME, "login")))

def login(self):
        self.getusernametextbox.send_keys("myuser@gmail.com")
        self.getpasswordtextbox.send_keys("12345678")
        self.getloginbutton.click()

Form1.cs

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;

public class ImageHelper
{

public Image CropImage(Image img)
{
    int x = img.Width/2;
    int y = img.Height/2;
    int r = Math.Min(x, y);

    Bitmap tmp = null;
    tmp = new Bitmap(2 * r, 2 * r);
    using (Graphics g = Graphics.FromImage(tmp))
    {
        g.SmoothingMode = SmoothingMode.AntiAlias;
        g.TranslateTransform(tmp.Width / 2, tmp.Height / 2);
        GraphicsPath gp = new GraphicsPath();
        gp.AddEllipse(0 - r, 0 - r, 2 * r, 2 * r);
        Region rg = new Region(gp);
        g.SetClip(rg, CombineMode.Replace);
        Bitmap bmp = new Bitmap(img);
        g.DrawImage(bmp, new Rectangle(-r, -r, 2 * r, 2 * r), new Rectangle(x - r, y - r, 2 * r, 2 * r), GraphicsUnit.Pixel);

    }


        return tmp;
}
public void SaveImage(Image img,string path,ImageFormat imageFormat)
{
    img.Save(path, imageFormat);
}

}

}