OpenCV

问题 I'd like to digitize a heatmap, Panel D in this source image As a first step, I tried to read the image in opencv and obtain a matrix import cv2 from pprint import pprint def read_as_digital(image): # mage dimensions h = image.shape[0] w = image.shape[1] print(h, w) pass if __name__ == '__main__': image = cv2.imread('ip.jpg', 1) pprint(image) read_as_digital(image) I could read the image as a matrix, but I don't know how to specify the beginning of the cells (corresponding to different

问题 I'd like to digitize a heatmap, Panel D in this source image As a first step, I tried to read the image in opencv and obtain a matrix import cv2 from pprint import pprint def read_as_digital(image): # mage dimensions h = image.shape[0] w = image.shape[1] print(h, w) pass if __name__ == '__main__': image = cv2.imread('ip.jpg', 1) pprint(image) read_as_digital(image) I could read the image as a matrix, but I don't know how to specify the beginning of the cells (corresponding to different

问题 I am writing a code on Jupyter notebook using python to recognize the number on the device with 7segment(FND). I used opencv and got the edge of the image. import cv2 import matplotlib.pyplot as plt def detect_edge(image): ''' function Detecting Edges ''' image_with_edges = cv2.Canny(image , 100, 200) images = [image , image_with_edges] location = [121, 122] for loc, img in zip(location, images): plt.subplot(loc) plt.imshow(img, cmap='gray') plt.savefig('edge.png') plt.show() image = cv2

问题 I want to remove anything other than text from a license plate with a binary filter. I have the projections on each axis but I don't know how to apply it. My idea is to erase the white outlines. This is the image I'm working for now: This is the projection in Axis X: from matplotlib import pyplot as plt import pylab (rows,cols)=img.shape h_projection = np.array([ x/255/rows for x in img.sum(axis=0)]) plt.plot(range(cols), h_projection.T) And this is the result: As you can see in the graph, at

问题 I want to remove anything other than text from a license plate with a binary filter. I have the projections on each axis but I don't know how to apply it. My idea is to erase the white outlines. This is the image I'm working for now: This is the projection in Axis X: from matplotlib import pyplot as plt import pylab (rows,cols)=img.shape h_projection = np.array([ x/255/rows for x in img.sum(axis=0)]) plt.plot(range(cols), h_projection.T) And this is the result: As you can see in the graph, at

问题 I am trying to run this code here https://github.com/feichtenhofer/gpu_flow/ which requires me to first install OpenCV 2.4. But I get the error below when trying to do so and I read that this means the version is no longer supported. So how can I install OpenCV version 2.4? user:~$ pip install opencv-python==2.4 WARNING: Keyring is skipped due to an exception: Failed to unlock the collection! WARNING: Keyring is skipped due to an exception: Failed to unlock the collection! ERROR: Could not

问题 What I'm trying to do: the user loads an image in html opencv receives that image in C++ and do some work on it. What I've done is more or less the same as described here : https://answers.opencv.org/question/222994/how-to-pass-image-data-from-javascript-to-opencv-c-webassembly/ Here is the javascript part (verbatim from the given link): var openFile = function (e) { const fileReader = new FileReader(); fileReader.onload = (event) => { const uint8Arr = new Uint8Array(event.target.result);

问题 I wanted to create a blank alpha image to parse some data from py-opencv and save it on an transparent background png file. I tried : blank_image = np.zeros((H,W,4), np.uint8) and blank_image = np.full((H, W, 4) , (0, 0, 0, 0), np.uint8) (H and W are Height and Width) Both still render a black background instead of a transparent one. how to get a blank alpha transparent image? Thanks in advance :) Edits: as mentioned by Mark Setchell: you need to specify the alpha channel on other colors

问题 I wanted to create a blank alpha image to parse some data from py-opencv and save it on an transparent background png file. I tried : blank_image = np.zeros((H,W,4), np.uint8) and blank_image = np.full((H, W, 4) , (0, 0, 0, 0), np.uint8) (H and W are Height and Width) Both still render a black background instead of a transparent one. how to get a blank alpha transparent image? Thanks in advance :) Edits: as mentioned by Mark Setchell: you need to specify the alpha channel on other colors

问题 I wanted to create a blank alpha image to parse some data from py-opencv and save it on an transparent background png file. I tried : blank_image = np.zeros((H,W,4), np.uint8) and blank_image = np.full((H, W, 4) , (0, 0, 0, 0), np.uint8) (H and W are Height and Width) Both still render a black background instead of a transparent one. how to get a blank alpha transparent image? Thanks in advance :) Edits: as mentioned by Mark Setchell: you need to specify the alpha channel on other colors