[教學]C# EmguCV教學-圖像基礎處理篇 @ 一個小小工程師的心情抒發天地

自從開始學習EmguCV後，越來越覺得這玩意有一種相見恨晚的感覺，

這玩意比起MFC來說，真的快很多啊............，而且真的不難，

甚至在Compression上面，也有很好的表現，

比起MFC來說，這傢伙簡直完勝，

所以.......我決定下一次的Project，就用它來搞定了

這次要教的是各種圖像的基礎應用以及處理，

廢話不多說，咱們直接寫點Code吧 !

1. 創建一個圖片

private void btn_CreatePhoto_Click(object sender, EventArgs e)
        {
            // Create an image.
            Image<Rgb, byte> image = new Image<Rgb, byte>(320, 240, new Rgb(255, 0,0 ));
            imageBox1.Image = image ;
        }

有沒有 !!! 就是這麼簡單。

2. 打開一張圖片

private void btn_CreatePhoto_Click(object sender, EventArgs e)
        {
            // Create an image.
            Image image = new Image(320, 240, new Rgb(255, 0,0 ));
            imageBox1.Image = image ;
        }

3. 從ImageBox裡面Copy圖片




 Image _picture = null;
        private void btn_CopyImg_Click(object sender, EventArgs e)
        {
            if(_picture == null)
            {
                _picture = new Image(new Bitmap(imageBox1.Image.Bitmap));
                imageBox1.Image = _picture;
            }
            else
            {
                imageBox1.Image = _picture;
            }
        }

4. 畫一些什麼，在圖片上面




        private void btn_Draw_Click(object sender, EventArgs e)
        {
            // 創建一張白色長寬為 200 * 200的圖片
            Image img = new Image(200, 200,
                new Bgr(255, 255, 255));
            // 創建一個矩形，左上角坐標為 (80,80)大小為(40,40)
            Rectangle rect = new Rectangle(new Point(80, 80),
                new Size(40, 40));
            // 創建一個中心點座標為 (100,100)半徑為40的圓形
            CircleF circlef = new CircleF(new PointF(100, 100), 40);


            string str = "Eric";
            // 創建Point類型做為字符串的左上角坐標
            Point str_location = new Point(0, 30);
            img.Draw(rect, new Bgr(0, 255, 0), 2);// 指定參數繪畫矩形
            img.Draw(circlef,new Bgr(0,0,255),3); // 指定參數繪畫圓形
            img.Draw(str,str_location,Emgu.CV.CvEnum.FontFace.HersheyComplexSmall,
                1, new Bgr(255,0,0),3); //指定參數繪畫字體
            imageBox1.Image = img;
        }

5. Draw Polyline




        private void btn_DrawPolyline_Click(object sender, EventArgs e)
        {
            // 創建一個隨機數產生器
            Random m = new Random();
            // 創建一張200*200的白色圖片
            Image img = new Image(
                200, 200, new Bgr(255, 255, 255));
            
            // 創建一個三個三點數組
            Point[] pt1 = new Point[3];
            Point[] pt2 = new Point[3];
            Point[] pt3 = new Point[3];
            for (int i =0 ; i< 3 ;i++)
            {
                pt1[i] = new Point(m.Next(0, 200), m.Next(0, 200));
                pt2[i] = new Point(m.Next(0, 200), m.Next(0, 200));
                pt3[i] = new Point(m.Next(0, 200), m.Next(0, 200));
            }
            Point[][] pts = new Point[2][];
            pts[0] = pt2;
            pts[1] = pt3;

            img.DrawPolyline(pt1, true, new Bgr(0, 0, 255), 2);
            img.DrawPolyline(pts,true,new Bgr(255,0,0),3);
            imageBox1.Image = img; 
        }

6. 使用Mat來Draw

補充 : Mat 是在Emgucv3.0之後才出來。



private void btn_DrawMat_Click(object sender, EventArgs e)
        {
            Image img = new Image(200, 200,
                new Bgr(255, 255, 255));
            Mat mat = img.Mat;
            CvInvoke.PutText(mat, "Hello world",
                new Point(0, 30), Emgu.CV.CvEnum.FontFace.HersheyComplexSmall,
                1, new MCvScalar(255, 0, 0), 3);
            Rectangle rect = new Rectangle(new Point(80, 80),
                new Size(40,40));
            CvInvoke.Rectangle(mat, rect, new MCvScalar(0, 255, 0), 2);
            CvInvoke.Circle(mat, new Point(100, 100), 40,
                new MCvScalar(0, 0, 255), 3);
            imageBox1.Image = mat;
        }

7. 圖像遍歷- 三種方式

 // 第二種方式
           
        private void btn_DrawMat_Click(object sender, EventArgs e)
        {
            Image img = new Image(200, 200,
                new Bgr(255, 255, 255));
            Mat mat = img.Mat;
            CvInvoke.PutText(mat, "Hello world",
                new Point(0, 30), Emgu.CV.CvEnum.FontFace.HersheyComplexSmall,
                1, new MCvScalar(255, 0, 0), 3);
            Rectangle rect = new Rectangle(new Point(80, 80),
                new Size(40,40));
            CvInvoke.Rectangle(mat, rect, new MCvScalar(0, 255, 0), 2);
            CvInvoke.Circle(mat, new Point(100, 100), 40,
                new MCvScalar(0, 0, 255), 3);
            imageBox1.Image = mat;
        }

        private void btn_rec_Click(object sender, EventArgs e)
        {
            Image img_1 = new Image(320, 240,
                new Bgr(255, 0, 0));
            // 第一種方式
#if false
            
            Byte b1 = 255;
            for (int i = 20; i < 60 ; i++)
            {
                for (int j = 20; j < 60; j++)
                {
                    img_1.Data[i, j, 0] = 0 ; // 第一通道的某個座標進行賦值
                    img_1.Data[i, j, 1] = b1; // 第二通道的某個座標進行賦值
                    img_1.Data[i, j, 2] = b1; // 第三通道的某個座標進行賦值
                }
            }

            // 第二種方式
            Bgr _Yellow = new Bgr(0, 255, 255);
            for (int i = 120; i < 160; i++)
            {
                for (int j = 20 ; j < 60 ; j++)
                {
                    img_1[i, j] = _Yellow; // 對某個位置進行顏色空間賦值
                }
            }
#endif
            Byte b1 = 255;
            byte[, ,] data = img_1.Data; //取得img數據轉成byte三維數組數據.
            for (int i = 20; i < 60; i++)
            {
                for (int j = 100; j < 140 ;j++)
                {
                    data[i, j, 0] = 0;
                    data[i, j, 1] = b1;
                    data[i, j, 2] = b1;

                }
            }
            imageBox1.Image = img_1;
        }