Even then, there are questions about how close the lines are to the boundary versus other lines, and what exactly would be extended to what.Īnother approach is to loop through all of the polygons, river banks in this example, select all of the lines that are within a given polygon, and extend those lines using one of a variety of techniques to match up with each containing polygon. To write text with OpenCV there is cv2.putText() function that accepts a number of arguments.Ĭv2.putText(my_img, 'Tutorials Point', (50, 50),font, 0.8, (255, 0, 0), 2, cv2.My first thought was Extend line, as Dan already mentioned, but then I remembered that it operates within a single feature class, which would involve creating a new, intermediate data set that includes the boundaries of the polygons.

This function needs five number of arguments. Rotation angle of the ellipse (calculated counterclockwise).Length of the minor and major axes (h, w).Image object on which image to be drawn.This function accepts eight input parameters.

This function accepts five input parameters.Ĭv2.circle(my_img, (200, 200), 80, (0, 20, 200), 10)įor drawing an ellipse, cv2.ellipse() function is used.

Coordinates of the lower right vertex (x, y).

Coordinates of the vertex at the top left (x, y).

This function accepts five input parameters. My_img = np.zeros((350, 350, 3), dtype = 'uint8')įor drawing a line cv2.line() function is used. Also as example an arrow to indicate something.Ĭv2.line() − This function is used to draw line on an image.Ĭv2.rectangle() − This function is used to draw rectangle on an image.Ĭv2.circle() − This function is used to draw circle on an image.Ĭv2.putText() − This function is used to write text on image.Ĭv2.ellipse() − This function is used to draw ellipse on image.

Often working with image analysis, we want to highlight a portion of the image, for example by adding a rectangle that defines that portion. The ability to add different geometric shapes just like lines, circles and rectangle etc. The basic operations of OpenCV is to draw over images.

Draw polygon python