cv::findContours cv::findContours is a function in OpenCV used to find the contours of objects in images. Contours are the boundaries of objects and are commonly used for object detection, segmentation, and shape analysis. The basic usage of the cv::findContours function is as follows: cv::findContours(image, contours, hierarchy, mode, method, offset = cv::Point(0, 0)); image: The input […]
Tag: contour
Understanding of merging of halcon contour algorithm
************************************************Contour merge: two Connect the outlines************************************************ *************************************************** ************ gen_contour_polygon_xld (FirstContour, [500,1000], [1,1]) gen_contour_polygon_xld (SecondContour, [1000,500], [2000,2000]) gen_contour_polygon_xld (SecondContour1, [1000,500], [500,1001]) gen_contour_polygon_xld (SecondContour2, [1000,500], [3000,3000]) gen_contour_polygon_xld (SecondContour1, [500,1000], [500,1001]) * gen_contour_polygon_xld (SecondContour1, [1000,1000], [1000,500]) concat_obj (FirstContour, SecondContour1, ConcatContour) concat_obj(ConcatContour, SecondContour, ConcatContour) concat_obj(ConcatContour, SecondContour2, ConcatContour) *Returns the length of the contour distance_cc(ConcatContour, ConcatContour, ‘point_to_segment’, DistanceMin, DistanceMax) *Returns […]
[Python Ocean Topic 10] Cartopy draws terrain contour maps of specific areas
[Python Ocean Topic 10] Cartopy draws terrain contour maps of specific areas Ocean and Atmospheric Sciences The previous issues can be considered to be about the drawing methods of plane elements This issue is about plane painting in specific areas Global regional bathymetry map Contents of this issue Drawing a floor plan of a specific […]
[Python Ocean Topic 8] Cartopy adjusts the number of contourf filling intervals for drawing topographic and bathymetric maps
[Python Ocean Topic 8] Cartopy adjusts the number of contourf filling intervals for drawing topographic and bathymetric maps article Sometimes I want to make the contourf picture more detailed. At this time, it is necessary to increase the number of filling intervals Contents of this issue 1: The number of fillings in contourf changes cf […]
[Python Ocean Topic 9] Cartopy draws terrain contour maps
[Python Ocean Topic 9] Cartopy draws terrain contour maps The basics of the water depth chart are almost the same, and can be replaced by temperature, salinity, etc. This issue plus depth contours Contents of this issue 1: Topographic contours cf = ax.contour(lon, lat, ele[:, :], levels=np.linspace(-9000,-100,10), colors=’gray’, linestyles=’-‘, linewidths=0.25, transform=ccrs.PlateCarree()) 2: Change color colors=’gray’ […]
WRF post-processing | contour plot drawing
Drawing process: Drawing the contour plot of the WRF (Weather Research and Forecasting) model requires the use of WRF data and the wrf-python library, Matplotlib library or other drawing libraries. Here are the general steps to plot a contour plot of a WRF model: Get WRF data: First, you need to get the output data […]
OpenCV—009 (target detection–contour detection)
Contour Detection Image contour refers to the boundary of the object in the image and is the external feature of the image object. Discovery and drawing of contours The outline of the image can not only provide the edges of the object, but also provide the hierarchical relationship and topological relationship between the edges of […]
OpenCV contour approximation-polygon fitting, bounding rectangle and bounding circle
Introduction Contour Approximation refers to approximating or fitting the contour to obtain an approximate contour. In image processing, contours represent the boundaries of objects in an image, so contour approximation can be used to describe and identify the shape of objects. Polygon fitting Polygon fitting (Approximating Polygons) is to approximate the outline into a polygon […]
How to find and plot the convex hull of an image contour in OpenCV Python?
The convex hull looks similar to a contour approximation, but it is not exactly a contour approximation. A convex hull is a convex curve surrounding an object. Convex curves are always bulging or at least flat. Convex hull can find convexity defects and correct them. Syntax To find the convex hull we use the following […]
OpenCV Python How to find the shortest distance between a point and a contour in an image?
We can use cv2.pointPolygonTest() to calculate the shortest distance between a point on the image and the contour, passing the contour point coordinates and point coordinates as parameters to it. Before using cv2.pointPolygonTest() we need to calculate the contours in the image. We can follow the following steps to find the shortest distance between a […]