画线 cv::line （LINE_4\LINE_8\LINE_AA） 画椭圆cv::ellipse 画矩形cv::rectangle 画圆cv::circle 画填充cv::fillPoly 画文字cv::putText #include "../common/common.hpp" static Mat bgImage; static void drawLines(); static void drawRectangle(); static void drawEllipse(); static void drawCircle(); static void drawPolygon(); static void drawRandomLine(); void main1_8(int argc, char** argv) { bgImage = imread(getCVImagesPath("images/test1.png"), IMREAD_COLOR); drawLines(); drawRectangle(); drawEllipse(); drawCircle(); drawPolygon(); //参数：Mat，文字(不识别中文?)，文字的位置(锚点?)，字体，缩放，颜色，线宽，线类型 putText(bgImage, "Hello OpenCV", Point(0, 200), CV_FONT_HERSHEY_COMPLEX, 1.0, Scalar(0), 3, LINE_8);//绘制文字 imshow("src", bgImage); drawRandomLine(); waitKey(0); } void drawLines()//绘制线条 { Point p1 = Point(20, 30);//Point表示平面上的点，OpenCV中的这些坐标值都是相对于图像本身像素值的 Point p2; p2.x = 400; p2.y = 400; Scalar color = Scalar(0, 0, 255); line(bgImage, p1, p2, color, 10, LINE_AA);//绘制线条到Mat，10是线宽、LINE_4或LINE_8是带锯齿的，LINE_AA是抗锯齿的 } void drawRectangle()//绘制矩形 { //OpenCV的坐标系，原点在屏幕左上角，x朝右正，y朝下正 Rect rect = Rect(200, 100, 300, 300);//起始位置x、y，宽，高 Scalar color = Scalar(255, 0, 0); rectangle(bgImage, rect, color, LINE_8);//绘制矩形到Mat，自带圆角。。 } void drawEllipse()//绘制椭圆 { int width = bgImage.cols; int height = bgImage.rows; Scalar color = Scalar(0, 255, 0); //绘制椭圆，参数：Mat，中心点，椭圆的长短轴半径，椭圆的朝向(0表示水平)，起始角度，终点角度 ellipse(bgImage, Point(width / 2, height / 2), Size(width / 4, height / 8), 0, 0, 270, color, 2, LINE_8); } void drawCircle()//绘制圆 { Scalar color = Scalar(0, 255, 255); circle(bgImage, Point(bgImage.cols / 2, bgImage.rows / 2), 150, color, 2, LINE_8); } void drawPolygon()//绘制多边形，绘制的多边形是填充的 { Point pts[1][5]; pts[0][0] = Point(100, 100); pts[0][1] = Point(100, 200); pts[0][2] = Point(200, 200); pts[0][3] = Point(200, 100); pts[0][4] = Point(100, 100); const Point * ppts[] = { pts[0] }; int npt[] = { 5 }; Scalar color = Scalar(255, 0, 255); //参数：Mat，顶点数据指针，顶点个数，1表示只绘制一个contour(轮廓) fillPoly(bgImage, ppts, npt, 1, color, LINE_8); } void drawRandomLine()//循环绘制随机位置随机颜色的线段 { Mat randomLineMat = Mat::zeros(bgImage.size(), bgImage.type()); RNG rng(12345);//生成高斯随机数，参数种子 Point p1, p2; for (int i = 0; i < 100000; i++) { p1.x = rng.uniform(0, randomLineMat.cols);//生成正态分布 0-bgImage.cols 范围内的随机数 p1.y = rng.uniform(0, randomLineMat.rows); p2.x = rng.uniform(0, randomLineMat.cols); p2.y = rng.uniform(0, randomLineMat.rows); Scalar color = Scalar(rng.uniform(0, 255), rng.uniform(0, 255), rng.uniform(0, 255)); if (waitKey(50) > 0)//参数delay如果传0表示阻塞等待键盘事件，传大于0表示只阻塞等待delay毫秒，键盘无响应返回-1 { break; } line(randomLineMat, p1, p2, color, 1, LINE_8); imshow("randomLine", randomLineMat); } } 
@BindView(R.id.iv_cv1_8_input) ImageView mSrcIv; @BindView(R.id.iv_cv1_8_output1) ImageView mRandomLineIv; private Bitmap mSrcBmp; private Bitmap mRandomLineBmp; private Mat mSrcMat = new Mat(); private Mat mRandomLineMat; private volatile boolean isStop; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_cv1_8); mUnbinder = ButterKnife.bind(this); //src mSrcBmp = CV310Utils.getBitmapFromAssets(this, "opencv/test1.png"); Utils.bitmapToMat(mSrcBmp, mSrcMat); drawLine(); drawRectangle(); drawEllipse(); drawCircle(); drawPolygon(); //参数：Mat，文字(不识别中文?)，文字的位置(锚点?)，字体，缩放，颜色，线宽，线类型，固定false Imgproc.putText(mSrcMat, "Hello OpenCV", new Point(0, 100), Core.FONT_HERSHEY_COMPLEX, 1.0, new Scalar(0), 3, Imgproc.LINE_8, false);//绘制文字 Imgproc.putText(mSrcMat, "中文", new Point(0, 200), Core.FONT_HERSHEY_COMPLEX, 1.0, new Scalar(0), 3, Imgproc.LINE_8, false); CV310Utils.mat2bitmapAndShowInIv(mSrcMat, mSrcBmp, mSrcIv); //random line mRandomLineIv.post(new Runnable() { @Override public void run() { new Thread(){ @Override public void run() { drawRandomLine(mRandomLineIv.getWidth(), mRandomLineIv.getHeight()); } }.start(); } }); } /*画线*/ private void drawLine() { Point p1 = new Point(20, 30);//Point表示平面上的点，OpenCV中的这些坐标值都是相对于图像本身像素值的 Point p2 = new Point(400, 400); Scalar color = new Scalar(255, 0, 0, 255);//因为bitmap是ARGB_8888的，所以Scalar要传alpha Imgproc.line(mSrcMat, p1, p2, color, 10, Imgproc.LINE_AA, 0);//绘制线条到Mat，10是线宽、LINE_4或LINE_8是带锯齿的，LINE_AA是抗锯齿的，参数shift固定传0 } /*画矩形*/ private void drawRectangle() { //Rect rect = new Rect(200, 100, 300, 300);//起始位置x、y，宽，高 Scalar color = new Scalar(0, 0, 255, 255); //OpenCV的坐标系，原点在屏幕左上角，x朝右正，y朝下正，参数：Mat，矩形坐上点 右下点 Imgproc.rectangle(mSrcMat, new Point(200, 100), new Point(500, 400), color, Imgproc.LINE_8);//绘制矩形到Mat，自带圆角。。 } /*绘制椭圆*/ private void drawEllipse() { int width = mSrcMat.cols(); int height = mSrcMat.rows(); Scalar color = new Scalar(0, 255, 0, 255); //绘制椭圆，参数：Mat，中心点，椭圆的长短轴半径，椭圆的朝向(0表示水平)，起始角度，终点角度 Imgproc.ellipse(mSrcMat, new Point(width / 2, height / 2), new Size(width / 4, height / 8), 0, 0, 270, color, 2, Imgproc.LINE_8, 0); } /*绘制圆*/ private void drawCircle() { Scalar color = new Scalar(255, 255, 0, 255); Imgproc.circle(mSrcMat, new Point(mSrcMat.cols()/2, mSrcMat.rows()/2), 150, color, 2, Imgproc.LINE_8, 0); } /*绘制多边形，绘制的多边形是填充的*/ private void drawPolygon() { List<MatOfPoint> pts = new ArrayList<>(); //需要这样组织顶点数据，否则绘制不出来 pts.add(new MatOfPoint(new Point(100, 100), new Point(100, 200), new Point(200, 200), new Point(200, 100), new Point(100, 100))); //同样的顶点，与c++绘制出来的地方偏差了100。。 pts.add(new MatOfPoint(new Point(100, 300), new Point(100, 400), new Point(200, 400), new Point(200, 300), new Point(100, 300))); Scalar color = new Scalar(255, 0, 255, 255); Imgproc.fillPoly(mSrcMat, pts, color, Imgproc.LINE_8, 0, new Point(100, 100));//pts.size()多少就绘制几个多边形 } /*循环绘制随机位置随机颜色的线段*/ private void drawRandomLine(int width, int height) { mRandomLineBmp = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565); mRandomLineMat = Mat.zeros(new Size(width, height), mSrcMat.type()); Random random = new Random(); Point p1 = new Point(); Point p2 = new Point(); for (int i = 0; i < 100000; i++) { p1.x = random.nextInt(width); p1.y = random.nextInt(height); p2.x = random.nextInt(width); p2.y = random.nextInt(height); Scalar color = new Scalar(random.nextInt(255), random.nextInt(255), random.nextInt(255), 255);//线段与颜色都随机 if (isStop) { break; } else { try { Thread.sleep(50); } catch (InterruptedException e) { e.printStackTrace(); } } Imgproc.line(mRandomLineMat, p1, p2, color, 1, Imgproc.LINE_8, 0); runOnUiThread(new Runnable() { @Override public void run() { CV310Utils.mat2bitmapAndShowInIv(mRandomLineMat, mRandomLineBmp, mRandomLineIv); } }); } } @OnClick({R.id.btn_cv1_8_stop}) void click(View view) { switch (view.getId()) { case R.id.btn_cv1_8_stop: isStop = true; break; } } @Override protected void onDestroy() { super.onDestroy(); isStop = true; } 
文章来源: OpenCV之图像处理(八) 绘制形状与文字