Image size (Python, OpenCV)

Question

I would like to get the Image size in python,as I do it with c++.

int w = src->width;
printf("%d", 'w');

Answer 1

Using openCV and numpy it is as easy as this:

import cv2

img = cv2.imread('path/to/img',0)
height, width = img.shape[:2]

Answer 2

For me the easiest way is to take all the values returned by image.shape:

height, width, channels = img.shape

if you don't want the number of channels (useful to determine if the image is bgr or grayscale) just drop the value:

height, width, _ = img.shape

Answer 3

Use the function GetSize from the module cv with your image as parameter. It returns width, height as a tuple with 2 elements:

width, height = cv.GetSize(src)

Answer 4

I use numpy.size() to do the same:

import numpy as np
import cv2

image = cv2.imread('image.jpg')
height = np.size(image, 0)
width = np.size(image, 1)

Answer 5

from this tutorial: https://www.tutorialkart.com/opencv/python/opencv-python-get-image-size/

import cv2

# read image
img = cv2.imread('/home/ubuntu/Walnut.jpg', cv2.IMREAD_UNCHANGED)

# get dimensions of image
dimensions = img.shape

# height, width, number of channels in image

height = img.shape[0]
width = img.shape[1]
channels = img.shape[2]

---

from this other tutorial: https://www.pyimagesearch.com/2018/07/19/opencv-tutorial-a-guide-to-learn-opencv/

image = cv2.imread("jp.png")

(h, w, d) = image.shape

Please double check things before posting answers.

Answer 6

Here is a method that returns the image dimensions:

from PIL import Image
import os

def get_image_dimensions(imagefile):
    """
    Helper function that returns the image dimentions

    :param: imagefile str (path to image)
    :return dict (of the form: {width:<int>, height=<int>, size_bytes=<size_bytes>)
    """
    # Inline import for PIL because it is not a common library
    with Image.open(imagefile) as img:
        # Calculate the width and hight of an image
        width, height = img.size

    # calculat ethe size in bytes
    size_bytes = os.path.getsize(imagefile)

    return dict(width=width, height=height, size_bytes=size_bytes)

Answer 7

我相信简单的img.shape[-1::-1]会更好。

Answer 8

You can use image.shape to get the dimensions of the image. It returns 3 values. The first value is height of an image, the second is width, and the last one is number of channels. You don't need the last value here so you can use below code to get height and width of image:

height, width = src.shape[:2]
print(width, height)

Answer 9

We can use frame = cv2.resize(frame, (width,height)) here is a simple example -

import cv2
import numpy as np


frame = cv2.imread("temp/i.jpg")
frame = cv2.resize(frame, (500,500))
cv2.imshow('frame', frame)



if cv2.waitKey(1) & 0xFF == ord('q'):
    break
cv2.destroyAllWindows()