TiffImagePlugin.py 文件源码

def setup(self):
        # Reset everything.
        self.f.seek(self.beginning, os.SEEK_SET)

        self.whereToWriteNewIFDOffset = None
        self.offsetOfNewPage = 0

        self.IIMM = IIMM = self.f.read(4)
        if not IIMM:
            # empty file - first page
            self.isFirst = True
            return

        self.isFirst = False
        if IIMM == b"II\x2a\x00":
            self.setEndian("<")
        elif IIMM == b"MM\x00\x2a":
            self.setEndian(">")
        else:
            raise RuntimeError("Invalid TIFF file header")

        self.skipIFDs()
        self.goToEnd()