image_utils.py

import cv2
import urllib.request
import numpy as np
from bs4 import BeautifulSoup as BS

def resizeAndPad(img, size, padColor=0):
    h, w = img.shape[:2]
    sh, sw = size

    # interpolation method
    if h > sh or w > sw: # shrinking image
        interp = cv2.INTER_AREA
    else: # stretching image
        interp = cv2.INTER_CUBIC

    # aspect ratio of image
    aspect = w/h  # if on Python 2, you might need to cast as a float: float(w)/h

    # compute scaling and pad sizing
    if aspect > 1: # horizontal image
        new_w = sw
        new_h = np.round(new_w/aspect).astype(int)
        pad_vert = (sh-new_h)/2
        pad_top, pad_bot = np.floor(pad_vert).astype(int), np.ceil(pad_vert).astype(int)
        pad_left, pad_right = 0, 0
    elif aspect < 1: # vertical image
        new_h = sh
        new_w = np.round(new_h*aspect).astype(int)
        pad_horz = (sw-new_w)/2
        pad_left, pad_right = np.floor(pad_horz).astype(int), np.ceil(pad_horz).astype(int)
        pad_top, pad_bot = 0, 0
    else: # square image
        new_h, new_w = sh, sw
        pad_left, pad_right, pad_top, pad_bot = 0, 0, 0, 0

    # set pad color
    if len(img.shape) is 3 and not isinstance(padColor, (list, tuple, np.ndarray)): # color image but only one color provided
        padColor = [padColor]*3

    # scale and pad
    scaled_img = cv2.resize(img, (new_w, new_h), interpolation=interp)
    scaled_img = cv2.copyMakeBorder(scaled_img, pad_top, pad_bot, pad_left, pad_right, borderType=cv2.BORDER_CONSTANT, value=padColor)

    return scaled_img

def get_image_from_wikiart_url(wikiart_url):
    r = urllib.request.urlopen(wikiart_url).read()
    soup = BS(r)
    image_url = soup.find("meta", property="og:image")["content"]
    img_req = urllib.request.urlopen(image_url)
    img_arr = np.asarray(bytearray(img_req.read()), dtype=np.uint8)
    img = cv2.imdecode(img_arr, -1)  # 'Load it as it is'

    if len(img.shape) == 2:
        img = cv2.cvtColor(img, cv2.COLOR_GRAY2RGB)

    if img.shape[2] == 4:
        img = img[:, :, :3]

    return img