how to read images from my home directory and resize it

Question

I am trying to read the images and resize the image in my home directory file but didn't work please help how to read images and resize it.

    import cv2
    from PIL import Image
    img = cv2.resize(cv2.read('C://Users//NanduCn//jupter1//train-scene classification//train"', (28, 28)))


---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-103-dab0f11a9e2d> in <module>()
      1 import cv2
      2 from PIL import Image
----> 3 img = cv2.resize(cv2.read('C://Users//NanduCn//jupter1//train-scene classification//train"', (28, 28)))

AttributeError: module 'cv2.cv2' has no attribute 'read'

Answer 1

To read all images of particular extension, e.g. "*.png", one can use cv::glob function

void loadImages(const std::string& ext, const std::string& path, std::vector<cv::Mat>& imgs, const int& mode)
{
    std::vector<cv::String> strBuffer;
    cv::glob(cv::String{path} + cv::String{"/*."} + cv::String{ext}, strBuffer, false);

    for (auto& it : strBuffer)
    {
        imgs.push_back(cv::imread(it, mode));
    }
}

std::vector<cv::Mat> imgs;
loadImages("*.png", "/home/img", imgs, cv::IMREAD_COLOR);

And then resize each image in buffer

for (auto& it : imgs)
{
    cv::resize(it, it, cv::Size{WIDTH, HEIGHT});
}

It should be easy to rewrite to python since almost all functions / data types have equivalents in python.

filenames = glob("/home/img/*.png").sort()
images = [cv2.imread(img) for img in filenames]

for img in images:
    cv2.resize(img, (WIDTH, HEIGHT))

The code is divided to parts instead of one-liner because it is more readable, at least for me.