How to compare first frame to other frame of video opencv python

import cv2 cap = cv2.VideoCapture(input_path) count = 0 n=0 while True: ret, frame = cap.read() if ret: # You can do processing on this frame variabqle roi = frame[343:…

Turning an Open CV frame into a Base64 encoded JPEG

I want to take a frame from an Open CV webcam stream, produce a JPEG thumbnail and then encode it as Base64 (It will then be sent as an MQTT message, but this is not the problem). My Python “…

OpenCV – Detect points along a curve

I need to detect the points along these curves, in particular I need the position on the image of one of the two points starting from the left: I tried to detect Hough Points like that: import cv2 …

Bounding box detection for characters / digits

I have images, which look like the following: I want to find the bounding boxes for the 8 digits. My first try was to use cv2 with the following code: import cv2 import matplotlib.pyplot as plt …

Adaptive Threshold error: (-215:Assertion failed) src.type() == CV_8UC1 in function ‘adaptiveThreshold’

I am working on pre-trained vgg16 model, for that I need to have input size of image file to be (224,224,3). The code I am working on is: from tensorflow.keras.preprocessing import image import cv2 …

Detect rectangles in an image with Python

I have a large collection of binary images like these ones: On each image I need to detect the white rectangle. The rectangles have different dimensions and orientations and sometimes they are …

numpy image float array, to int 0..255 value

I got 3 NumPy data arrays r,g,b represented as a 2D float64 array (720×1024) Essentially per row, each channel is a bunch of floats: [[0.94984896 0.96076077 0.9599071 … 0.80338298 0.80253267 0….

Avoid recursion error with cv2 and mouse callback

I have a class for opening up an image and drawing circles. The entire code can be found here: p1 and p2 store diametrically opposing points on a circle. These are capture with click and drag actions …

Represent a video as a 2D Array where each column represents a frame – OpenCV and Python

My goal is to transform a video into a 2D matrix X, where the column vectors represent a frame. So the matrix has the dimension: X.shape —> (# features of a frame, # total number of frames) I …

Drawing a contour in a specific region of an image and finding the outermost contour in opencv-python

My code selects a frame from a video which is than subtracted with a background frame selected from the same video. It is then converted to grayscale, blurred, and then an image threshold is applied. …