如何在python中向量化任务？

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我(将)有一个坐标列表；使用python的pillow模块，我想将一系列(裁剪的)较小的图像保存到磁盘上。目前，我使用for循环一次确定一个坐标，然后在继续到下一个坐标之前裁剪/保存图像。

有没有一种方法可以划分这项工作，以便可以同时裁剪/保存多个图像？我知道这会占用更多的内存，但会减少性能时间。

我确信这是可能的，但我不确定这是否简单。我听说过像“矢量化”和“多线程”这样的术语，它们听起来似乎很适合这种情况。但这些话题超出了我的经验。

我附上了代码以供参考。然而，我只是想征求推荐的策略。(例如，我应该学习什么技术来更好地调整我的方法，一次接受多个作物，等等？)

def parse_image(source, square_size, count, captures, offset=0, offset_type=0, print_coords=False):
    """
    Starts at top left corner of image. Iterates through image by square_size (width = height)
    across x values and after exhausting the row, begins next row lower by function of 
    square_size. Offset parameter is available such that, with multiple function calls, 
    overlapping images could be generated.
    """
    src = Image.open(source)
    dimensions = src.size
    max_down = int(src.height/square_size) * square_size + square_size
    max_right = int(src.width/square_size) * square_size + square_size

    if offset_type == 1:
        tl_x = 0 + offset
        tl_y = 0
        br_x = square_size + offset 
        br_y = square_size

        for y in range(square_size,max_down,square_size):
            for x in range(square_size + offset,max_right - offset,square_size):
                if (tl_x,tl_y) not in captures:
                    sample = src.crop((tl_x,tl_y,br_x,br_y))
                    sample.save(f"{source[:-4]}_sample_{count}_x{tl_x}_y{tl_y}.jpg")
                    captures.append((tl_x,tl_y))

                    if print_coords == True: 
                        print(f"image {count}: top-left (x,y): {(tl_x,tl_y)}, bottom-right (x,y): {(br_x,br_y)}")
                    tl_x = x
                    br_x = x + square_size
                    count +=1                
                else:
                    continue
            tl_x = 0 + offset
            br_x = square_size + offset
            tl_y = y
            br_y = y + square_size
    else:
        tl_x = 0
        tl_y = 0 + offset
        br_x = square_size 
        br_y = square_size + offset

        for y in range(square_size + offset,max_down - offset,square_size):
            for x in range(square_size,max_right,square_size):
                if (tl_x,tl_y) not in captures:
                    sample = src.crop((tl_x,tl_y,br_x,br_y))
                    sample.save(f"{source[:-4]}_sample_{count}_x{tl_x}_y{tl_y}.jpg")
                    captures.append((tl_x,tl_y))

                    if print_coords == True: 
                        print(f"image {count}: top-left (x,y): {(tl_x,tl_y)}, bottom-right (x,y): {(br_x,br_y)}")
                    tl_x = x
                    br_x = x + square_size
                    count +=1
                else:
                    continue
            tl_x = 0
            br_x = square_size 
            tl_y = y + offset
            br_y = y + square_size + offset
    return count

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