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.
#
from __future__ import annotations

import abc
import os
import shutil
import subprocess
import sys
from shlex import quote
from typing import Any

from . import Image

_viewers = []


[docs] def register(viewer, order: int = 1) -> None: """ The :py:func:`register` function is used to register additional viewers:: from PIL import ImageShow ImageShow.register(MyViewer()) # MyViewer will be used as a last resort ImageShow.register(MySecondViewer(), 0) # MySecondViewer will be prioritised ImageShow.register(ImageShow.XVViewer(), 0) # XVViewer will be prioritised :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: Image.Image, title: str | None = None, **options: Any) -> bool: 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 True return False
[docs] class Viewer: """Base class for viewers.""" # main api
[docs] def show(self, image: Image.Image, **options: Any) -> int: """ The main function for displaying an image. Converts the given image to the target format and displays it. """ 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: str | None = None """The format to convert the image into.""" options: dict[str, Any] = {} """Additional options used to convert the image."""
[docs] def get_format(self, image: Image.Image) -> str | None: """Return format name, or ``None`` to save as PGM/PPM.""" return self.format
[docs] def get_command(self, file: str, **options: Any) -> str: """ Returns the command used to display the file. Not implemented in the base class. """ msg = "unavailable in base viewer" raise NotImplementedError(msg)
[docs] def save_image(self, image: Image.Image) -> str: """Save to temporary file and return filename.""" return image._dump(format=self.get_format(image), **self.options)
[docs] def show_image(self, image: Image.Image, **options: Any) -> int: """Display the given image.""" return self.show_file(self.save_image(image), **options)
[docs] def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ os.system(self.get_command(path, **options)) # nosec 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, "save_all": True} def get_command(self, file: str, **options: Any) -> str: return ( f'start "Pillow" /WAIT "{file}" ' "&& ping -n 4 127.0.0.1 >NUL " f'&& del /f "{file}"' ) def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ subprocess.Popen( self.get_command(path, **options), shell=True, creationflags=getattr(subprocess, "CREATE_NO_WINDOW"), ) # nosec return 1
if sys.platform == "win32": register(WindowsViewer)
[docs] class MacViewer(Viewer): """The default viewer on macOS using ``Preview.app``.""" format = "PNG" options = {"compress_level": 1, "save_all": True} def get_command(self, file: str, **options: Any) -> str: # on darwin open returns immediately resulting in the temp # file removal while app is opening command = "open -a Preview.app" command = f"({command} {quote(file)}; sleep 20; rm -f {quote(file)})&" return command def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ subprocess.call(["open", "-a", "Preview.app", path]) executable = sys.executable or shutil.which("python3") if executable: subprocess.Popen( [ executable, "-c", "import os, sys, time; time.sleep(20); os.remove(sys.argv[1])", path, ] ) return 1
if sys.platform == "darwin": register(MacViewer)
[docs] class UnixViewer(Viewer): format = "PNG" options = {"compress_level": 1, "save_all": True} @abc.abstractmethod def get_command_ex(self, file: str, **options: Any) -> tuple[str, str]: pass def get_command(self, file: str, **options: Any) -> str: command = self.get_command_ex(file, **options)[0] return f"({command} {quote(file)}"
class XDGViewer(UnixViewer): """ The freedesktop.org ``xdg-open`` command. """ def get_command_ex(self, file: str, **options: Any) -> tuple[str, str]: command = executable = "xdg-open" return command, executable def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ subprocess.Popen(["xdg-open", path]) return 1 class DisplayViewer(UnixViewer): """ The ImageMagick ``display`` command. This viewer supports the ``title`` parameter. """ def get_command_ex( self, file: str, title: str | None = None, **options: Any ) -> tuple[str, str]: command = executable = "display" if title: command += f" -title {quote(title)}" return command, executable def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ args = ["display"] title = options.get("title") if title: args += ["-title", title] args.append(path) subprocess.Popen(args) return 1 class GmDisplayViewer(UnixViewer): """The GraphicsMagick ``gm display`` command.""" def get_command_ex(self, file: str, **options: Any) -> tuple[str, str]: executable = "gm" command = "gm display" return command, executable def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ subprocess.Popen(["gm", "display", path]) return 1 class EogViewer(UnixViewer): """The GNOME Image Viewer ``eog`` command.""" def get_command_ex(self, file: str, **options: Any) -> tuple[str, str]: executable = "eog" command = "eog -n" return command, executable def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ subprocess.Popen(["eog", "-n", path]) return 1 class XVViewer(UnixViewer): """ The X Viewer ``xv`` command. This viewer supports the ``title`` parameter. """ def get_command_ex( self, file: str, title: str | None = None, **options: Any ) -> tuple[str, str]: # note: xv is pretty outdated. most modern systems have # imagemagick's display command instead. command = executable = "xv" if title: command += f" -name {quote(title)}" return command, executable def show_file(self, path: str, **options: Any) -> int: """ Display given file. """ args = ["xv"] title = options.get("title") if title: args += ["-name", title] args.append(path) subprocess.Popen(args) return 1 if sys.platform not in ("win32", "darwin"): # unixoids if shutil.which("xdg-open"): register(XDGViewer) if shutil.which("display"): register(DisplayViewer) if shutil.which("gm"): register(GmDisplayViewer) if shutil.which("eog"): register(EogViewer) if shutil.which("xv"): register(XVViewer)
[docs] class IPythonViewer(Viewer): """The viewer for IPython frontends.""" def show_image(self, image: Image.Image, **options: Any) -> int: ipython_display(image) return 1
try: from IPython.display import display as ipython_display except ImportError: pass else: register(IPythonViewer) if __name__ == "__main__": if len(sys.argv) < 2: print("Syntax: python3 ImageShow.py imagefile [title]") sys.exit() with Image.open(sys.argv[1]) as im: print(show(im, *sys.argv[2:]))