问题
I have an image that is 6400 × 3200, while my screen is 1280 x 800. Therefore, the image needs to be resized for display only. I am using Python and OpenCV 2.4.9. According to OpenCV Documentation,
If you need to show an image that is bigger than the screen resolution, you will need to call namedWindow("", WINDOW_NORMAL) before the imshow.
That is what I am doing, but the image is not fitted to the screen, only a portion is shown because it's too big. I've also tried with cv2.resizeWindow, but it doesn't make any difference.
import cv2
cv2.namedWindow("output", cv2.WINDOW_NORMAL) # Create window with freedom of dimensions
# cv2.resizeWindow("output", 400, 300) # Resize window to specified dimensions
im = cv2.imread("earth.jpg") # Read image
cv2.imshow("output", im) # Show image
cv2.waitKey(0) # Display the image infinitely until any keypress
回答1:
Although I was expecting an automatic solution (fitting to the screen automatically), resizing solves the problem as well.
import cv2
cv2.namedWindow("output", cv2.WINDOW_NORMAL) # Create window with freedom of dimensions
im = cv2.imread("earth.jpg") # Read image
imS = cv2.resize(im, (960, 540)) # Resize image
cv2.imshow("output", imS) # Show image
cv2.waitKey(0) # Display the image infinitely until any keypress
回答2:
The other answers perform a fixed (width, height)
resize. If you wanted to resize to a specific size while maintaining aspect ratio, use this
def ResizeWithAspectRatio(image, width=None, height=None, inter=cv2.INTER_AREA):
dim = None
(h, w) = image.shape[:2]
if width is None and height is None:
return image
if width is None:
r = height / float(h)
dim = (int(w * r), height)
else:
r = width / float(w)
dim = (width, int(h * r))
return cv2.resize(image, dim, interpolation=inter)
Example
image = cv2.imread('img.png')
resize = ResizeWithAspectRatio(image, width=1280) # Resize by width OR
# resize = ResizeWithAspectRatio(image, height=1280) # Resize by height
cv2.imshow('resize', resize)
cv2.waitKey()
回答3:
Try this:
image = cv2.imread("img/Demo.jpg")
image = cv2.resize(image,(240,240))
The image
is now resized. Displaying it will render in 240x240.
回答4:
In opencv, cv.namedWindow() just creates a window object as you determine, but not resizing the original image. You can use cv2.resize(img, resolution) to solve the problem.
Here's what it displays, a 740 * 411 resolution image.
image = cv2.imread("740*411.jpg")
cv2.imshow("image", image)
cv2.waitKey(0)
cv2.destroyAllWindows()
Here, it displays a 100 * 200 resolution image after resizing. Remember the resolution parameter use column first then is row.
image = cv2.imread("740*411.jpg")
image = cv2.resize(image, (200, 100))
cv2.imshow("image", image)
cv2.waitKey(0)
cv2.destroyAllWindows()
来源:https://stackoverflow.com/questions/35180764/opencv-python-image-too-big-to-display