emulate-sign-and-scan/emulate_sign_and_scan.py

import subprocess
from typing import NamedTuple

from towhee.operator.base import Operator
from towhee.types import Image


class EmulateSignAndScan(Operator):
    """
    A one line summary of this class.

    Args:
        init_arg_1 (`xxx`):
            This argument is ...
    """
    def __init__(self) -> None:
        super().__init__()

    def __call__(self, doc_path: str, out_path: str, sig_img: Image = None, x_off: int = 0, y_off: int = 0) -> NamedTuple('Outputs', [('out_path', str)]):
        """
        A one line summary of this function.

        Args:
            doc_path (`str`):
                Document which needs to be signed and scanned in PDF format.

            out_path (`str`):
                Output document path.

            sig_img (`towhee.types.Image`):
                Image containing the cropped signature

            x_off (`int`):
                `x` offset value (used to place the signature in the document.).

            y_off (`int`):
                `y` offset_value (used to place the signature in the document.)

        Returns:
            (`Tuple[('result_1', xxx)]`)
                A tuple with one values, which is ...
        """

        # step 1: copy signature image into document
        if sig_img:
            cv2.imwrite(sig_img.to_ndarray(), "/tmp/pdf2scan-sig-img.jpg")
            cmd = ["composite",
                   "-density", "150",
                   "-gravity", "NorthWest",
                   "-geometry", "+{0}+{1}".format(x_off, y_off),
                   "/tmp/pdf2scan-sig-img.jpg",
                   doc_path,
                   out_path]
        else:
            cmd = ["cp", doc_path, out_path]
        subprocess.call(cmd)

        # step 2: "scanify" the document
        cmd = ["convert",
               "-density", "150",
               out_path,
               "-rotate", "-0.66",
               "-attenuate", "0.2",
               "+noise", "Multiplicative",
               "-colorspace", "Gray",
               "-blur", "3x0.5",
               out_path]
        subprocess.call(cmd)

        Output = NamedTuple('Output', [('out_path', str)])
        return Output(out_path)