def METHOD_NAME(gt_box_list, fg_anchor_list):
    px, py, pw, ph = (
        fg_anchor_list[:, 0],
        fg_anchor_list[:, 1],
        fg_anchor_list[:, 2],
        fg_anchor_list[:, 3],
    )
    gx, gy, gw, gh = (
        gt_box_list[:, 0],
        gt_box_list[:, 1],
        gt_box_list[:, 2],
        gt_box_list[:, 3],
    )
    dx = (gx - px) / pw
    dy = (gy - py) / ph
    dw = np.log(gw / pw)
    dh = np.log(gh / ph)
    return np.stack((dx, dy, dw, dh), axis=1)