Source code for PIL.ImageShow

#
# The Python Imaging Library.
# $Id$
#
# im.show() drivers
#
# History:
# 2008-04-06 fl   Created
#
# Copyright (c) Secret Labs AB 2008.
#
# See the README file for information on usage and redistribution.
#
import os
import shutil
import subprocess
import sys
import tempfile
from shlex import quote

from PIL import Image

_viewers = []


[docs]def register(viewer, order=1): """ The :py:func:`register` function is used to register additional viewers. :param viewer: The viewer to be registered. :param order: Zero or a negative integer to prepend this viewer to the list, a positive integer to append it. """ try: if issubclass(viewer, Viewer): viewer = viewer() except TypeError: pass # raised if viewer wasn't a class if order > 0: _viewers.append(viewer) else: _viewers.insert(0, viewer)
[docs]def show(image, title=None, **options): r""" Display a given image. :param image: An image object. :param title: Optional title. Not all viewers can display the title. :param \**options: Additional viewer options. :returns: ``True`` if a suitable viewer was found, ``False`` otherwise. """ for viewer in _viewers: if viewer.show(image, title=title, **options): return 1 return 0
[docs]class Viewer: """Base class for viewers.""" # main api
[docs] def show(self, image, **options): """ The main function for displaying an image. Converts the given image to the target format and displays it. """ # save temporary image to disk if not ( image.mode in ("1", "RGBA") or (self.format == "PNG" and image.mode in ("I;16", "LA")) ): base = Image.getmodebase(image.mode) if image.mode != base: image = image.convert(base) return self.show_image(image, **options)
# hook methods format = None """The format to convert the image into.""" options = {} """Additional options used to convert the image."""
[docs] def get_format(self, image): """Return format name, or ``None`` to save as PGM/PPM.""" return self.format
[docs] def get_command(self, file, **options): """ Returns the command used to display the file. Not implemented in the base class. """ raise NotImplementedError
[docs] def save_image(self, image): """Save to temporary file and return filename.""" return image._dump(format=self.get_format(image), **self.options)
[docs] def show_image(self, image, **options): """Display the given image.""" return self.show_file(self.save_image(image), **options)
[docs] def show_file(self, file, **options): """Display the given file.""" os.system(self.get_command(file, **options)) return 1
# --------------------------------------------------------------------
[docs]class WindowsViewer(Viewer): """The default viewer on Windows is the default system application for PNG files.""" format = "PNG" options = {"compress_level": 1} def get_command(self, file, **options): return ( 'start "Pillow" /WAIT "%s" ' "&& ping -n 2 127.0.0.1 >NUL " '&& del /f "%s"' % (file, file) )
if sys.platform == "win32": register(WindowsViewer)
[docs]class MacViewer(Viewer): """The default viewer on MacOS using ``Preview.app``.""" format = "PNG" options = {"compress_level": 1} def get_command(self, file, **options): # on darwin open returns immediately resulting in the temp # file removal while app is opening command = "open -a Preview.app" command = "({} {}; sleep 20; rm -f {})&".format( command, quote(file), quote(file) ) return command def show_file(self, file, **options): """Display given file""" fd, path = tempfile.mkstemp() with os.fdopen(fd, "w") as f: f.write(file) with open(path, "r") as f: subprocess.Popen( ["im=$(cat); open -a Preview.app $im; sleep 20; rm -f $im"], shell=True, stdin=f, ) os.remove(path) return 1
if sys.platform == "darwin": register(MacViewer)
[docs]class UnixViewer(Viewer): format = "PNG" options = {"compress_level": 1} def get_command(self, file, **options): command = self.get_command_ex(file, **options)[0] return "({} {}; rm -f {})&".format(command, quote(file), quote(file)) def show_file(self, file, **options): """Display given file""" fd, path = tempfile.mkstemp() with os.fdopen(fd, "w") as f: f.write(file) with open(path, "r") as f: command = self.get_command_ex(file, **options)[0] subprocess.Popen( ["im=$(cat);" + command + " $im; rm -f $im"], shell=True, stdin=f ) os.remove(path) return 1
class DisplayViewer(UnixViewer): """The ImageMagick ``display`` command.""" def get_command_ex(self, file, **options): command = executable = "display" return command, executable class EogViewer(UnixViewer): """The GNOME Image Viewer ``eog`` command.""" def get_command_ex(self, file, **options): command = executable = "eog" return command, executable class XVViewer(UnixViewer): """ The X Viewer ``xv`` command. This viewer supports the ``title`` parameter. """ def get_command_ex(self, file, title=None, **options): # note: xv is pretty outdated. most modern systems have # imagemagick's display command instead. command = executable = "xv" if title: command += " -name %s" % quote(title) return command, executable if sys.platform not in ("win32", "darwin"): # unixoids if shutil.which("display"): register(DisplayViewer) if shutil.which("eog"): register(EogViewer) if shutil.which("xv"): register(XVViewer) if __name__ == "__main__": if len(sys.argv) < 2: print("Syntax: python ImageShow.py imagefile [title]") sys.exit() with Image.open(sys.argv[1]) as im: print(show(im, *sys.argv[2:]))