PIL.ImageTk 源代码

#
# The Python Imaging Library.
# $Id$
#
# a Tk display interface
#
# History:
# 96-04-08 fl   Created
# 96-09-06 fl   Added getimage method
# 96-11-01 fl   Rewritten, removed image attribute and crop method
# 97-05-09 fl   Use PyImagingPaste method instead of image type
# 97-05-12 fl   Minor tweaks to match the IFUNC95 interface
# 97-05-17 fl   Support the "pilbitmap" booster patch
# 97-06-05 fl   Added file= and data= argument to image constructors
# 98-03-09 fl   Added width and height methods to Image classes
# 98-07-02 fl   Use default mode for "P" images without palette attribute
# 98-07-02 fl   Explicitly destroy Tkinter image objects
# 99-07-24 fl   Support multiple Tk interpreters (from Greg Couch)
# 99-07-26 fl   Automatically hook into Tkinter (if possible)
# 99-08-15 fl   Hook uses _imagingtk instead of _imaging
#
# Copyright (c) 1997-1999 by Secret Labs AB
# Copyright (c) 1996-1997 by Fredrik Lundh
#
# See the README file for information on usage and redistribution.
#

try:
    import tkinter
except ImportError:
    import Tkinter
    tkinter = Tkinter
    del Tkinter

from PIL import Image
from io import BytesIO


# --------------------------------------------------------------------
# Check for Tkinter interface hooks

_pilbitmap_ok = None


def _pilbitmap_check():
    global _pilbitmap_ok
    if _pilbitmap_ok is None:
        try:
            im = Image.new("1", (1, 1))
            tkinter.BitmapImage(data="PIL:%d" % im.im.id)
            _pilbitmap_ok = 1
        except tkinter.TclError:
            _pilbitmap_ok = 0
    return _pilbitmap_ok

def _get_image_from_kw(kw):
    source = None
    if "file" in kw:
        source = kw.pop("file")
    elif "data" in kw:
        source = BytesIO(kw.pop("data"))
    if source:
        return Image.open(source)


# --------------------------------------------------------------------
# PhotoImage

[文档]class PhotoImage(object): """ A Tkinter-compatible photo image. This can be used everywhere Tkinter expects an image object. If the image is an RGBA image, pixels having alpha 0 are treated as transparent. The constructor takes either a PIL image, or a mode and a size. Alternatively, you can use the **file** or **data** options to initialize the photo image object. :param image: Either a PIL image, or a mode string. If a mode string is used, a size must also be given. :param size: If the first argument is a mode string, this defines the size of the image. :keyword file: A filename to load the image from (using ``Image.open(file)``). :keyword data: An 8-bit string containing image data (as loaded from an image file). """ def __init__(self, image=None, size=None, **kw): # Tk compatibility: file or data if image is None: image = _get_image_from_kw(kw) if hasattr(image, "mode") and hasattr(image, "size"): # got an image instead of a mode mode = image.mode if mode == "P": # palette mapped data image.load() try: mode = image.palette.mode except AttributeError: mode = "RGB" # default size = image.size kw["width"], kw["height"] = size else: mode = image image = None if mode not in ["1", "L", "RGB", "RGBA"]: mode = Image.getmodebase(mode) self.__mode = mode self.__size = size self.__photo = tkinter.PhotoImage(**kw) self.tk = self.__photo.tk if image: self.paste(image) def __del__(self): name = self.__photo.name self.__photo.name = None try: self.__photo.tk.call("image", "delete", name) except: pass # ignore internal errors def __str__(self): """ Get the Tkinter photo image identifier. This method is automatically called by Tkinter whenever a PhotoImage object is passed to a Tkinter method. :return: A Tkinter photo image identifier (a string). """ return str(self.__photo)
[文档] def width(self): """ Get the width of the image. :return: The width, in pixels. """ return self.__size[0]
[文档] def height(self): """ Get the height of the image. :return: The height, in pixels. """ return self.__size[1]
[文档] def paste(self, im, box=None): """ Paste a PIL image into the photo image. Note that this can be very slow if the photo image is displayed. :param im: A PIL image. The size must match the target region. If the mode does not match, the image is converted to the mode of the bitmap image. :param box: A 4-tuple defining the left, upper, right, and lower pixel coordinate. If None is given instead of a tuple, all of the image is assumed. """ # convert to blittable im.load() image = im.im if image.isblock() and im.mode == self.__mode: block = image else: block = image.new_block(self.__mode, im.size) image.convert2(block, image) # convert directly between buffers tk = self.__photo.tk try: tk.call("PyImagingPhoto", self.__photo, block.id) except tkinter.TclError: # activate Tkinter hook try: from PIL import _imagingtk try: _imagingtk.tkinit(tk.interpaddr(), 1) except AttributeError: _imagingtk.tkinit(id(tk), 0) tk.call("PyImagingPhoto", self.__photo, block.id) except (ImportError, AttributeError, tkinter.TclError): raise # configuration problem; cannot attach to Tkinter
# -------------------------------------------------------------------- # BitmapImage
[文档]class BitmapImage(object): """ A Tkinter-compatible bitmap image. This can be used everywhere Tkinter expects an image object. The given image must have mode "1". Pixels having value 0 are treated as transparent. Options, if any, are passed on to Tkinter. The most commonly used option is **foreground**, which is used to specify the color for the non-transparent parts. See the Tkinter documentation for information on how to specify colours. :param image: A PIL image. """ def __init__(self, image=None, **kw): # Tk compatibility: file or data if image is None: image = _get_image_from_kw(kw) self.__mode = image.mode self.__size = image.size if _pilbitmap_check(): # fast way (requires the pilbitmap booster patch) image.load() kw["data"] = "PIL:%d" % image.im.id self.__im = image # must keep a reference else: # slow but safe way kw["data"] = image.tobitmap() self.__photo = tkinter.BitmapImage(**kw) def __del__(self): name = self.__photo.name self.__photo.name = None try: self.__photo.tk.call("image", "delete", name) except: pass # ignore internal errors
[文档] def width(self): """ Get the width of the image. :return: The width, in pixels. """ return self.__size[0]
[文档] def height(self): """ Get the height of the image. :return: The height, in pixels. """ return self.__size[1]
def __str__(self): """ Get the Tkinter bitmap image identifier. This method is automatically called by Tkinter whenever a BitmapImage object is passed to a Tkinter method. :return: A Tkinter bitmap image identifier (a string). """ return str(self.__photo)
def getimage(photo): """Copies the contents of a PhotoImage to a PIL image memory.""" photo.tk.call("PyImagingPhotoGet", photo) # -------------------------------------------------------------------- # Helper for the Image.show method. def _show(image, title): class UI(tkinter.Label): def __init__(self, master, im): if im.mode == "1": self.image = BitmapImage(im, foreground="white", master=master) else: self.image = PhotoImage(im, master=master) tkinter.Label.__init__(self, master, image=self.image, bg="black", bd=0) if not tkinter._default_root: raise IOError("tkinter not initialized") top = tkinter.Toplevel() if title: top.title(title) UI(top, image).pack()