from PIL import Image
import matplotlib.pyplot as plt

def SpliceImage(img_1, img_2, save_img, mode=None):
    '''
    把兩張圖片左右拼接
    
    img_1   : 輸入圖片1(左)的路徑
    img_2   : 輸入圖片2(右)的路徑
    save_img: 保存圖片的路徑
    mode    : 默認為 None ，寬度保持不變，高度取最大值
              可設為'mean'，寬度與高度均取兩張圖片的平均值
    '''
    # -----get width and height of the Images----- #
    img1 = Image.open(img_1)
    img2 = Image.open(img_2)
    w1, h1 = img1.size
    w2, h2 = img2.size
    print("原始圖片1大小：{} x {}" .format(w1,h1))
    print("原始圖片2大?。簕} x {}" .format(w2,h2))
    
    # -----resize image with high-quality----- #
    if mode == 'mean':
        width = int((w1 + w2) / 2)
        height = int((h1 + h2) / 2)
        w1 = int(width/2)
        w2 = int(width/2)
    else:
        width = w1 + w2
        height = max(h1,h2)
        
    img1 = img1.resize((w1, height), Image.ANTIALIAS) 
    img2 = img2.resize((w2, height), Image.ANTIALIAS) 
    
    # -----create a new image-----#
    img = Image.new("RGB", (width, height), (0,0,0))
    img.paste(img1, (0,0))
    img.paste(img2, (w1,0))
    img.save(save_img)
    print("輸出圖片大?。簕} x {}" .format(width,height))
    
    return img

if __name__ == '__main__':
    img_1 = r'.\img\sleeper.PNG'
    img_2 = r'.\img\dog.PNG'
    save_img = r'.\img\getup.jpg'
    try:
        img = SpliceImage(img_1, img_2, save_img, mode='mean')
    except:
        print('Image file error!')
    plt.imshow(img)