image edge detection python

Document directory 1.1 cvkan 1.2 cvCreateTrackbar 1.3 CvTrackbarCallback [OpenCV Getting Started Guide] Part 3 "Canny edge detection" The principle of image edge detection is to detect all the gray-scale points in the image,

"OpenCV Getting Started" chapter III Canny edge detection The image edge detection principle is to detect the image of all the gray value changes in the larger point, and these points are connected to form a number of lines, thes

F=imread (' 0.jpg '); % read-in imageF=rgb2gray (f); % convert color images to grayscale imagesF=im2double (f); % conversion to double precision, easy to calculate laterPe=edge (F, ' Sobel ', ' horizontal ');%sobel levelFigure, Imshow (PE), title (' Sobel Image '),Figure, Imshow (f), title (' Original Image '),Pf=edge

Sobel Edge Detection algorithmReprint Please specify source: http://blog.csdn.net/tianhai110The Bell operator (Sobel operator) is mainly used for edge detection, and technically, it is a discrete difference operator, which is used to calculate the approximate value of the grayscale of the

The Bell operator (Sobel operator) is mainly used for edge detection, and technically, it is a discrete difference operator, which is used to calculate the approximate value of the grayscale of the image luminance function. Using this operator at any point in the image will produce a corresponding grayscale vector or i

The traditional canny edge detection algorithm is an effective and relatively simple algorithm, which can get good results (refer to the implementation of canny edge detection algorithm). But the canny algorithm itself has some flaws that can be improved.1. Canny edge

Reference Link: http://blog.csdn.net/zxw_xzr/article/details/77358815The internship company has the need for OCR recognition of VAT invoices. The OCR section is not difficult to implement (there is a ready-made SDK to call), but in practice, the invoices in the user-supplied photos tend to have some skew, and the company-provided OCR SDK does not detect skewed characters, so the image preprocessing is required first, and the positive invoice (the effe

The edge of the image is where the gray value of the image is mutated, that is, the pixel value of the image changes very quickly in that part, such as a curve on the axis has just begun smooth suddenly a big turn, in the variation of the derivative is very large.The Sobel operator is mainly used for

foreground), we don't have to separate the background. If there is no clear outline or contrast between the background and foreground of the Verification Code, let alone the machine, even the human eyes cannot identify it. Therefore, we set a reasonable "threshold" to split the image contour (the contrast is strong) by edge detection algorithm. However, it shoul

The edge of the image is where the gray value of the image is mutated, that is, the pixel value of the image changes very quickly in that part, such as a curve on the axis has just begun smooth suddenly a big turn, in the variation of the derivative is very large. The Sobel operator is mainly used for

The log edge detection operator first makes Gaussian filtering on the image and then the second derivative of Laplace (Laplacian). That is, the image is filtered with the Laplacian of the Gaussian function. Finally, the edge of the image