How can i select a part of a image using python?

I'm working with satellites images and i开发者_高级运维 need to select one part of the image to work if. How can i do it? Im.crop doesn't seen to work. Resize?

Thanks

from PIL import Image
im = Image.open("test.jpg")

crop_rectangle = (50, 50, 200, 200)
cropped_im = im.crop(crop_rectangle)

cropped_im.show()

Note that the crop region must be given as a 4-tuple - (left, upper, right, lower).

More details here Using the Image Class

To get a smaller image from the larger image, just use the array indexes

subImage=Image[ miny:maxy, minx:maxx ]

Here you can draw a rectangle over the image, to get it cropped

import numpy as np
import cv2
import matplotlib.pyplot as plt


def downloadImage(URL):
    """Downloads the image on the URL, and convers to cv2 BGR format"""
    from io import BytesIO
    from PIL import Image as PIL_Image
    import requests

    response = requests.get(URL)
    image = PIL_Image.open(BytesIO(response.content))
    return cv2.cvtColor(np.array(image), cv2.COLOR_BGR2RGB)


fig, ax = plt.subplots()

URL = "https://www.godan.info/sites/default/files/old/2015/04/Satellite.jpg"
img = downloadImage(URL)[:, :, ::-1]  # BGR->RGB
plt.imshow(img)

selectedRectangle = None
# Capture mouse-drawing-rectangle event
def line_select_callback(eclick, erelease):
    x1, y1 = eclick.xdata, eclick.ydata
    x2, y2 = erelease.xdata, erelease.ydata

    selectedRectangle = plt.Rectangle(
        (min(x1, x2), min(y1, y2)),
        np.abs(x1 - x2),
        np.abs(y1 - y2),
        color="r",
        fill=False,
    )
    ax.add_patch(selectedRectangle)

    imgOnRectangle = img[
        int(min(y1, y2)) : int(max(y1, y2)), int(min(x1, x2)) : int(max(x1, x2))
    ]
    plt.figure()
    plt.imshow(imgOnRectangle)
    plt.show()


from matplotlib.widgets import RectangleSelector

rs = RectangleSelector(
    ax,
    line_select_callback,
    drawtype="box",
    useblit=False,
    button=[1],
    minspanx=5,
    minspany=5,
    spancoords="pixels",
    interactive=True,
)

plt.show()