cv2 uses numpy for manipulating images, so the proper and best way to get the size of an image is using numpy.shape. Assuming you are working with BGR images, here is an example: >>> import numpy as np >>> import cv2 >>> img = cv2.imread(‘foo.jpg’) >>> height, width, channels = img.shape >>> print height, width, … Read more
This fixed the problem by having it as the first two lines of the script: !pip install opencv-python !apt update && apt install -y libsm6 libxext6 !apt-get install -y libxrender-dev
I had the same issue. I didn’t need to download anything else to solve this. CV2 had everything I needed. Instead of trying to figure out where the .xml files are and hard coding the values, I used a property given by cv2. From OP face_cascade = cv2.CascadeClassifier(‘haarcascade_frontalface_default.xml’) eye_cascade = cv2.CascadeClassifier(‘haarcascade_eye.xml’) Becomes face_cascade = cv2.CascadeClassifier(cv2.data.haarcascades … Read more
Here is a handy function you can use to help with identifying your opencv matrices at runtime. I find it useful for debugging, at least. string type2str(int type) { string r; uchar depth = type & CV_MAT_DEPTH_MASK; uchar chans = 1 + (type >> CV_CN_SHIFT); switch ( depth ) { case CV_8U: r = “8U”; … Read more
cv:Mat mat; int rows = mat.rows; int cols = mat.cols; cv::Size s = mat.size(); rows = s.height; cols = s.width;
use this: pil_image = PIL.Image.open(‘Image.jpg’).convert(‘RGB’) open_cv_image = numpy.array(pil_image) # Convert RGB to BGR open_cv_image = open_cv_image[:, :, ::-1].copy()
You can use newer OpenCV python interface (if I’m not mistaken it is available since OpenCV 2.2). It natively uses numpy arrays: import cv2 im = cv2.imread(“abc.tiff”,mode=”RGB”) print type(im) result: <type ‘numpy.ndarray’>
One general procedure is laid out in the Wikipedia article on unsharp masking: You use a Gaussian smoothing filter and subtract the smoothed version from the original image (in a weighted way so the values of a constant area remain constant). To get a sharpened version of frame into image: (both cv::Mat) cv::GaussianBlur(frame, image, cv::Size(0, … Read more
The below steps for using Android OpenCV sdk in Android Studio. This is a simplified version of this SO answer. Download latest OpenCV sdk for Android from OpenCV.org and decompress the zip file. Import OpenCV to Android Studio, From File -> New -> Import Module, choose sdk/java folder in the unzipped opencv archive. Update build.gradle … Read more
imshow() only works with waitKey(): import cv2 img = cv2.imread(‘C:/Python27/03323_HD.jpg’) cv2.imshow(‘ImageWindow’, img) cv2.waitKey() (The whole message-loop necessary for updating the window is hidden in there.)