def read_qr_code(self, buffer: ctypes.c_void_p,
                     buffer_size: int,  # overall image size in bytes
                     rowlen_bytes: int, # the scan line length in bytes. (many libs, such as OSX, expect this value to properly grok image data)
                     width: int, height: int, frame_id: int = -1) -> List[QrCodeResult]:
        """
        Reads a QR code from an image buffer in Y800 / GREY format.
        Returns a list of detected QR codes which includes their data and positions.
        """

        Reads a QR code from an image buffer in Y800 / GREY format.
        Returns a list of detected QR codes which includes their data and positions.
        
electrum/qrreader/abstract_base.py