Tkinter 画布缩放 + 移动/平移 [英] Tkinter canvas zoom + move/pan
本文介绍了Tkinter 画布缩放 + 移动/平移的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
Tkinter 的画布小部件具有以下内置功能:
使用
canvas.scan_mark和canvas.scan_dragto移动/平移画布(例如使用 Click + Drag)，请参阅 .在 Windows 7 64 位和 Python 3.6.2 上测试.
不要忘记在脚本末尾放置图像的路径.
# -*- 编码:utf-8 -*-# 高级缩放示例.就像在谷歌地图中一样.# 它只缩放一个图块，而不是整个图像.所以缩放的瓷砖占据# 恒定内存，而不是用一个巨大的调整大小的图像来进行大缩放.随机导入将 tkinter 作为 tk 导入从 tkinter 导入 ttk从 PIL 导入 Image、ImageTk类自动滚动条(ttk.Scrollbar):''' 一个滚动条，如果不需要它会隐藏自己.仅当您使用网格几何管理器 ''' 时才有效定义集(自我，你好，你好):如果 float(lo) <= 0.0 并且 float(hi) >= 1.0:self.grid_remove()别的:self.grid()ttk.Scrollbar.set(self, lo, hi)def包(自我，**千瓦):raise tk.TclError('不能使用带有这个小部件的包')def place(self, **kw):raise tk.TclError('Cannot use place with this widget')类 Zoom_Advanced(ttk.Frame):'''图像的高级缩放'''def __init__(self, mainframe, path):'''初始化主框架'''ttk.Frame.__init__(self, master=mainframe)self.master.title('用鼠标滚轮缩放')# 画布的垂直和水平滚动条vbar = AutoScrollbar(self.master, orient='vertical')hbar = AutoScrollbar(self.master, orient='horizontal')vbar.grid(row=0, column=1,sticky='ns')hbar.grid(row=1, column=0,sticky='we')# 创建画布并在其上放置图像self.canvas = tk.Canvas(self.master, highlightthickness=0,xscrollcommand=hbar.set, yscrollcommand=vbar.set)self.canvas.grid(row=0, column=0,sticky='nswe')self.canvas.update() # 等待画布被创建vbar.configure(command=self.scroll_y) # 将滚动条绑定到画布hbar.configure(command=self.scroll_x)# 使画布可展开self.master.rowconfigure(0, weight=1)self.master.columnconfigure(0, weight=1)# 绑定事件到画布self.canvas.bind('', self.show_image) # 调整画布大小self.canvas.bind(' ', self.move_from)self.canvas.bind(' ', self.move_to)self.canvas.bind('<MouseWheel>', self.wheel) # 适用于 Windows 和 MacOS，但不适用于 Linuxself.canvas.bind(' ', self.wheel) # 仅适用于 Linux，滚轮向下滚动self.canvas.bind(' ', self.wheel) # 仅适用于 Linux，滚轮向上滚动self.image = Image.open(path) # 打开图片self.width, self.height = self.image.sizeself.imscale = 1.0 # 画布图像的比例self.delta = 1.3 # 缩放幅度# 将图像放入容器矩形并使用它为图像设置适当的坐标self.container = self.canvas.create_rectangle(0, 0, self.width, self.height, width=0)# 为测试目的绘制一些可选的随机矩形最小尺寸、最大尺寸、数字 = 5、20、10对于范围内的 n(数字):x0 = random.randint(0, self.width - maxsize)y0 = random.randint(0, self.height - maxsize)x1 = x0 + random.randint(minsize, maxsize)y1 = y0 + random.randint(minsize, maxsize)color = ('red', 'orange', 'yellow', 'green', 'blue')[random.randint(0, 4)]self.canvas.create_rectangle(x0, y0, x1, y1, fill=color, activefill='black')self.show_image()def scroll_y(self, *args, **kwargs):''' 垂直滚动画布并重绘图像 '''self.canvas.yview(*args, **kwargs) # 垂直滚动self.show_image() # 重绘图像def scroll_x(self, *args, **kwargs):'''水平滚动画布并重绘图像'''self.canvas.xview(*args, **kwargs) # 水平滚动self.show_image() # 重绘图像def move_from(self, event):'''记住以前用鼠标滚动的坐标'''self.canvas.scan_mark(event.x, event.y)def move_to(self, event):''' 拖动(移动)画布到新位置 '''self.canvas.scan_dragto(event.x, event.y, gain=1)self.show_image() # 重绘图像定义轮(自我，事件):'''用鼠标滚轮缩放'''x = self.canvas.canvasx(event.x)y = self.canvas.canvasy(event.y)bbox = self.canvas.bbox(self.container) # 获取图片区域如果 bbox[0] <×＜bbox[2] 和 bbox[1] 我创建了更高级的缩放功能.有图像金字塔"用于平滑缩放大图像，甚至能够打开和缩放高达数 GB 的巨大 TIFF 文件.
版本 3.0 在 Windows 7 64 位和 Python 3.7 上测试.
# -*- 编码:utf-8 -*-# 各种类型图像的高级缩放，从小到大到几 GB导入数学进口警告将 tkinter 作为 tk 导入从 tkinter 导入 ttk从 PIL 导入 Image、ImageTk类自动滚动条(ttk.Scrollbar):"一个滚动条，如果不需要它会隐藏自己.仅适用于网格几何管理器"定义集(自我，你好，你好):如果 float(lo) <= 0.0 并且 float(hi) >= 1.0:self.grid_remove()别的:self.grid()ttk.Scrollbar.set(self, lo, hi)def包(自我，**千瓦):raise tk.TclError('Cannot use pack with the widget ' + self.__class__.__name__)def place(self, **kw):raise tk.TclError('Cannot use place with the widget ' + self.__class__.__name__)类 CanvasImage:"显示和缩放图像"def __init__(self, placeholder, path):"初始化ImageFrame"self.imscale = 1.0 # 画布图像缩放比例，外部类公开self.__delta = 1.3 # 缩放幅度self.__filter = Image.ANTIALIAS # 可以是:NEAREST、BILINEAR、BICUBIC 和 ANTIALIASself.__previous_state = 0 # 键盘之前的状态self.path = path # 图片的路径，对于外部类应该是公开的# 在占位符小部件中创建 ImageFrameself.__imframe = ttk.Frame(placeholder) # ImageFrame 对象的占位符# 画布的垂直和水平滚动条hbar = AutoScrollbar(self.__imframe, orient='horizontal')vbar = AutoScrollbar(self.__imframe, orient='vertical')hbar.grid(row=1, column=0,sticky='we')vbar.grid(row=0, column=1,sticky='ns')# 创建画布并将其与滚动条绑定.外部类的公共self.canvas = tk.Canvas(self.__imframe, highlightthickness=0,xscrollcommand=hbar.set, yscrollcommand=vbar.set)self.canvas.grid(row=0, column=0,sticky='nswe')self.canvas.update() # 等待画布被创建hbar.configure(command=self.__scroll_x) # 将滚动条绑定到画布vbar.configure(command=self.__scroll_y)# 绑定事件到画布self.canvas.bind('', lambda event: self.__show_image()) # canvas 被调整大小self.canvas.bind(' ', self.__move_from) # 记住画布位置self.canvas.bind(' ', self.__move_to) # 将画布移动到新位置self.canvas.bind('<MouseWheel>', self.__wheel) # 缩放适用于 Windows 和 MacOS，但不适用于 Linuxself.canvas.bind('<Button-5>', self.__wheel) # Linux 缩放，滚轮向下滚动self.canvas.bind(' ', self.__wheel) # Linux 缩放，滚轮向上滚动# 在空闲模式下处理击键，因为程序在弱计算机上变慢，# 当同时发生太多击键事件时self.canvas.bind(' ', lambda 事件:self.canvas.after_idle(self.__keystroke, event))# 决定这个图像是否巨大self.__huge = False # 是否巨大self.__huge_size = 14000 # 定义巨幅图像的大小self.__band_width = 1024 # tile band 的宽度Image.MAX_IMAGE_PIXELS = 1000000000 # 抑制大图的 DecompressionBombErrorwith warnings.catch_warnings(): # 抑制 DecompressionBombWarningwarnings.simplefilter('忽略')self.__image = Image.open(self.path) # 打开图片，但不加载self.imwidth, self.imheight = self.__image.size # 外部类公开如果 self.imwidth * self.imheight >self.__huge_size * self.__huge_size 和 self.__image.tile[0][0] == 'raw': # 只有原始图像可以平铺self.__huge = True # 图像很大self.__offset = self.__image.tile[0][2] # 初始瓦片偏移self.__tile = [self.__image.tile[0][0], # 它必须是 'raw'[0, 0, self.imwidth, 0], # 平铺范围(一个矩形)self.__offset,self.__image.tile[0][3]] # 解码器的参数列表self.__min_side = min(self.imwidth, self.imheight) # 获取较小的图像边# 创建图像金字塔self.__pyramid = [self.smaller()] if self.__huge else [Image.open(self.path)]# 设置图像金字塔的比率系数self.__ratio = max(self.imwidth, self.imheight)/self.__huge_size if self.__huge else 1.0self.__curr_img = 0 # 金字塔的当前图像self.__scale = self.imscale * self.__ratio # 图像金字塔比例self.__reduction = 2 # 图像金字塔的缩小程度w, h = self.__pyramid[-1].size当 w >512 和 h >512: # 顶部金字塔图像大小约为 512 像素w/= self.__reduction # 除以归约度h/= self.__reduction # 除以归约度self.__pyramid.append(self.__pyramid[-1].resize((int(w), int(h)), self.__filter))# 将图像放入容器矩形并使用它为图像设置适当的坐标self.container = self.canvas.create_rectangle((0, 0, self.imwidth, self.imheight), width=0)self.__show_image() # 在画布上显示图像self.canvas.focus_set() # 在画布上设置焦点定义更小(自我):"按比例调整图像大小并返回较小的图像"w1, h1 = float(self.imwidth), float(self.imheight)w2, h2 = float(self.__huge_size), float(self.__huge_size)aspect_ratio1 = w1/h1aspect_ratio2 = w2/h2 # 等于 1.0如果 aspect_ratio1 == aspect_ratio2:image = Image.new('RGB', (int(w2), int(h2)))k = h2/h1 # 压缩比w = int(w2) # 波段长度elif aspect_ratio1 >纵横比2:image = Image.new('RGB', (int(w2), int(w2/aspect_ratio1)))k = h2/w1 #压缩比w = int(w2) # 波段长度否则:#aspect_ratio1 0 和 int(y2 - y1) >0: # 如果图像在可见区域，则显示图像如果 self.__huge 和 self.__curr_img <0: # 显示大图h = int((y2 - y1)/self.imscale) # 瓷砖带的高度self.__tile[1][3] = h # 设置瓦带高度self.__tile[2] = self.__offset + self.imwidth * int(y1/self.imscale) * 3self.__image.close()self.__image = Image.open(self.path) # 重新打开/重置图像self.__image.size = (self.imwidth, h) # 设置tile band的大小self.__image.tile = [self.__tile]图像 = self.__image.crop((int(x1/self.imscale), 0, int(x2/self.imscale), h))else: # 显示正常图像image = self.__pyramid[max(0, self.__curr_img)].crop( # 从金字塔中裁剪当前 img(int(x1/self.__scale), int(y1/self.__scale),int(x2/self.__scale), int(y2/self.__scale)))#imagetk = ImageTk.PhotoImage(image.resize((int(x2 - x1), int(y2 - y1)), self.__filter))imageid = self.canvas.create_image(max(box_canvas[0], box_img_int[0]),最大(box_canvas[1]，box_img_int[1])，anchor='nw', image=imagetk)self.canvas.lower(imageid) # 设置图片为背景self.canvas.imagetk = imagetk # 保留一个额外的引用以防止垃圾收集def __move_from(self, event):"记住以前用鼠标"滚动的坐标self.canvas.scan_mark(event.x, event.y)def __move_to(self, event):"拖动(移动)画布到新位置"self.canvas.scan_dragto(event.x, event.y, gain=1)self.__show_image() # 缩放图块并将其显示在画布上定义外部(自我，x，y):"检查点 (x,y) 是否在图像区域"之外bbox = self.canvas.coords(self.container) # 获取图片区域如果 bbox[0] <×＜bbox[2] 和 bbox[1] 附言这是使用高级缩放的 GitHub 应用程序，用于使用多边形进行手动图像注释.>
Tkinter's canvas widget has built-in features to:
move/pan the canvas (for example with Click + Drag) with
canvas.scan_markandcanvas.scan_dragto, see this questionzoom the vector elements on the canvas with
canvas.scale, but sadly, this doesn't work for bitmap images on the canvas
Fortunately, this method allows zooming of images (by manually redrawing the zoomed portion of the image). But:
As we are redrawing a particular portion of the canvas, move/pan feature won't work anymore...
We absolutely need to render more than the currently displayed area, to allow move/pan. Let's say we have 1000x1000 bitmap on the canvas, and we want to zoom by a factor 50x... How to avoid having a 50.000 x 50.000 pixels bitmap in memory? (2.5 gigapixels in RAM is too big). We could think about rendering the viewport only, or a bit more than the current viewport to allow panning, but then what to do once panning leads to the edge of the rendered zone?
How to have a move/pan + zoom feature on Tkinter canvas, that works for images?
解决方案Advanced zoom example. Like in Google Maps.
Example video (longer video here):
It zooms only a tile, but not the whole image. So the zoomed tile occupies constant memory and not crams it with a huge resized image for the large zooms. For the simplified zoom example look here.
Tested on Windows 7 64-bit and Python 3.6.2.
Do not forget to place a path to your image at the end of the script.
# -*- coding: utf-8 -*- # Advanced zoom example. Like in Google Maps. # It zooms only a tile, but not the whole image. So the zoomed tile occupies # constant memory and not crams it with a huge resized image for the large zooms. import random import tkinter as tk from tkinter import ttk from PIL import Image, ImageTk class AutoScrollbar(ttk.Scrollbar): ''' A scrollbar that hides itself if it's not needed. Works only if you use the grid geometry manager ''' def set(self, lo, hi): if float(lo) <= 0.0 and float(hi) >= 1.0: self.grid_remove() else: self.grid() ttk.Scrollbar.set(self, lo, hi) def pack(self, **kw): raise tk.TclError('Cannot use pack with this widget') def place(self, **kw): raise tk.TclError('Cannot use place with this widget') class Zoom_Advanced(ttk.Frame): ''' Advanced zoom of the image ''' def __init__(self, mainframe, path): ''' Initialize the main Frame ''' ttk.Frame.__init__(self, master=mainframe) self.master.title('Zoom with mouse wheel') # Vertical and horizontal scrollbars for canvas vbar = AutoScrollbar(self.master, orient='vertical') hbar = AutoScrollbar(self.master, orient='horizontal') vbar.grid(row=0, column=1, sticky='ns') hbar.grid(row=1, column=0, sticky='we') # Create canvas and put image on it self.canvas = tk.Canvas(self.master, highlightthickness=0, xscrollcommand=hbar.set, yscrollcommand=vbar.set) self.canvas.grid(row=0, column=0, sticky='nswe') self.canvas.update() # wait till canvas is created vbar.configure(command=self.scroll_y) # bind scrollbars to the canvas hbar.configure(command=self.scroll_x) # Make the canvas expandable self.master.rowconfigure(0, weight=1) self.master.columnconfigure(0, weight=1) # Bind events to the Canvas self.canvas.bind('<Configure>', self.show_image) # canvas is resized self.canvas.bind('<ButtonPress-1>', self.move_from) self.canvas.bind('<B1-Motion>', self.move_to) self.canvas.bind('<MouseWheel>', self.wheel) # with Windows and MacOS, but not Linux self.canvas.bind('<Button-5>', self.wheel) # only with Linux, wheel scroll down self.canvas.bind('<Button-4>', self.wheel) # only with Linux, wheel scroll up self.image = Image.open(path) # open image self.width, self.height = self.image.size self.imscale = 1.0 # scale for the canvaas image self.delta = 1.3 # zoom magnitude # Put image into container rectangle and use it to set proper coordinates to the image self.container = self.canvas.create_rectangle(0, 0, self.width, self.height, width=0) # Plot some optional random rectangles for the test purposes minsize, maxsize, number = 5, 20, 10 for n in range(number): x0 = random.randint(0, self.width - maxsize) y0 = random.randint(0, self.height - maxsize) x1 = x0 + random.randint(minsize, maxsize) y1 = y0 + random.randint(minsize, maxsize) color = ('red', 'orange', 'yellow', 'green', 'blue')[random.randint(0, 4)] self.canvas.create_rectangle(x0, y0, x1, y1, fill=color, activefill='black') self.show_image() def scroll_y(self, *args, **kwargs): ''' Scroll canvas vertically and redraw the image ''' self.canvas.yview(*args, **kwargs) # scroll vertically self.show_image() # redraw the image def scroll_x(self, *args, **kwargs): ''' Scroll canvas horizontally and redraw the image ''' self.canvas.xview(*args, **kwargs) # scroll horizontally self.show_image() # redraw the image def move_from(self, event): ''' Remember previous coordinates for scrolling with the mouse ''' self.canvas.scan_mark(event.x, event.y) def move_to(self, event): ''' Drag (move) canvas to the new position ''' self.canvas.scan_dragto(event.x, event.y, gain=1) self.show_image() # redraw the image def wheel(self, event): ''' Zoom with mouse wheel ''' x = self.canvas.canvasx(event.x) y = self.canvas.canvasy(event.y) bbox = self.canvas.bbox(self.container) # get image area if bbox[0] < x < bbox[2] and bbox[1] < y < bbox[3]: pass # Ok! Inside the image else: return # zoom only inside image area scale = 1.0 # Respond to Linux (event.num) or Windows (event.delta) wheel event if event.num == 5 or event.delta == -120: # scroll down i = min(self.width, self.height) if int(i * self.imscale) < 30: return # image is less than 30 pixels self.imscale /= self.delta scale /= self.delta if event.num == 4 or event.delta == 120: # scroll up i = min(self.canvas.winfo_width(), self.canvas.winfo_height()) if i < self.imscale: return # 1 pixel is bigger than the visible area self.imscale *= self.delta scale *= self.delta self.canvas.scale('all', x, y, scale, scale) # rescale all canvas objects self.show_image() def show_image(self, event=None): ''' Show image on the Canvas ''' bbox1 = self.canvas.bbox(self.container) # get image area # Remove 1 pixel shift at the sides of the bbox1 bbox1 = (bbox1[0] + 1, bbox1[1] + 1, bbox1[2] - 1, bbox1[3] - 1) bbox2 = (self.canvas.canvasx(0), # get visible area of the canvas self.canvas.canvasy(0), self.canvas.canvasx(self.canvas.winfo_width()), self.canvas.canvasy(self.canvas.winfo_height())) bbox = [min(bbox1[0], bbox2[0]), min(bbox1[1], bbox2[1]), # get scroll region box max(bbox1[2], bbox2[2]), max(bbox1[3], bbox2[3])] if bbox[0] == bbox2[0] and bbox[2] == bbox2[2]: # whole image in the visible area bbox[0] = bbox1[0] bbox[2] = bbox1[2] if bbox[1] == bbox2[1] and bbox[3] == bbox2[3]: # whole image in the visible area bbox[1] = bbox1[1] bbox[3] = bbox1[3] self.canvas.configure(scrollregion=bbox) # set scroll region x1 = max(bbox2[0] - bbox1[0], 0) # get coordinates (x1,y1,x2,y2) of the image tile y1 = max(bbox2[1] - bbox1[1], 0) x2 = min(bbox2[2], bbox1[2]) - bbox1[0] y2 = min(bbox2[3], bbox1[3]) - bbox1[1] if int(x2 - x1) > 0 and int(y2 - y1) > 0: # show image if it in the visible area x = min(int(x2 / self.imscale), self.width) # sometimes it is larger on 1 pixel... y = min(int(y2 / self.imscale), self.height) # ...and sometimes not image = self.image.crop((int(x1 / self.imscale), int(y1 / self.imscale), x, y)) imagetk = ImageTk.PhotoImage(image.resize((int(x2 - x1), int(y2 - y1)))) imageid = self.canvas.create_image(max(bbox2[0], bbox1[0]), max(bbox2[1], bbox1[1]), anchor='nw', image=imagetk) self.canvas.lower(imageid) # set image into background self.canvas.imagetk = imagetk # keep an extra reference to prevent garbage-collection path = 'doge.jpg' # place path to your image here root = tk.Tk() app = Zoom_Advanced(root, path=path) root.mainloop()EDIT:
I've created even more advanced zoom. There is "image pyramid" for smooth zooming of large images and even ability to open and zoom huge TIFF files up to several gigabytes.
Version 3.0 is tested on Windows 7 64-bit and Python 3.7.
# -*- coding: utf-8 -*- # Advanced zoom for images of various types from small to huge up to several GB import math import warnings import tkinter as tk from tkinter import ttk from PIL import Image, ImageTk class AutoScrollbar(ttk.Scrollbar): """ A scrollbar that hides itself if it's not needed. Works only for grid geometry manager """ def set(self, lo, hi): if float(lo) <= 0.0 and float(hi) >= 1.0: self.grid_remove() else: self.grid() ttk.Scrollbar.set(self, lo, hi) def pack(self, **kw): raise tk.TclError('Cannot use pack with the widget ' + self.__class__.__name__) def place(self, **kw): raise tk.TclError('Cannot use place with the widget ' + self.__class__.__name__) class CanvasImage: """ Display and zoom image """ def __init__(self, placeholder, path): """ Initialize the ImageFrame """ self.imscale = 1.0 # scale for the canvas image zoom, public for outer classes self.__delta = 1.3 # zoom magnitude self.__filter = Image.ANTIALIAS # could be: NEAREST, BILINEAR, BICUBIC and ANTIALIAS self.__previous_state = 0 # previous state of the keyboard self.path = path # path to the image, should be public for outer classes # Create ImageFrame in placeholder widget self.__imframe = ttk.Frame(placeholder) # placeholder of the ImageFrame object # Vertical and horizontal scrollbars for canvas hbar = AutoScrollbar(self.__imframe, orient='horizontal') vbar = AutoScrollbar(self.__imframe, orient='vertical') hbar.grid(row=1, column=0, sticky='we') vbar.grid(row=0, column=1, sticky='ns') # Create canvas and bind it with scrollbars. Public for outer classes self.canvas = tk.Canvas(self.__imframe, highlightthickness=0, xscrollcommand=hbar.set, yscrollcommand=vbar.set) self.canvas.grid(row=0, column=0, sticky='nswe') self.canvas.update() # wait till canvas is created hbar.configure(command=self.__scroll_x) # bind scrollbars to the canvas vbar.configure(command=self.__scroll_y) # Bind events to the Canvas self.canvas.bind('<Configure>', lambda event: self.__show_image()) # canvas is resized self.canvas.bind('<ButtonPress-1>', self.__move_from) # remember canvas position self.canvas.bind('<B1-Motion>', self.__move_to) # move canvas to the new position self.canvas.bind('<MouseWheel>', self.__wheel) # zoom for Windows and MacOS, but not Linux self.canvas.bind('<Button-5>', self.__wheel) # zoom for Linux, wheel scroll down self.canvas.bind('<Button-4>', self.__wheel) # zoom for Linux, wheel scroll up # Handle keystrokes in idle mode, because program slows down on a weak computers, # when too many key stroke events in the same time self.canvas.bind('<Key>', lambda event: self.canvas.after_idle(self.__keystroke, event)) # Decide if this image huge or not self.__huge = False # huge or not self.__huge_size = 14000 # define size of the huge image self.__band_width = 1024 # width of the tile band Image.MAX_IMAGE_PIXELS = 1000000000 # suppress DecompressionBombError for the big image with warnings.catch_warnings(): # suppress DecompressionBombWarning warnings.simplefilter('ignore') self.__image = Image.open(self.path) # open image, but down't load it self.imwidth, self.imheight = self.__image.size # public for outer classes if self.imwidth * self.imheight > self.__huge_size * self.__huge_size and self.__image.tile[0][0] == 'raw': # only raw images could be tiled self.__huge = True # image is huge self.__offset = self.__image.tile[0][2] # initial tile offset self.__tile = [self.__image.tile[0][0], # it have to be 'raw' [0, 0, self.imwidth, 0], # tile extent (a rectangle) self.__offset, self.__image.tile[0][3]] # list of arguments to the decoder self.__min_side = min(self.imwidth, self.imheight) # get the smaller image side # Create image pyramid self.__pyramid = [self.smaller()] if self.__huge else [Image.open(self.path)] # Set ratio coefficient for image pyramid self.__ratio = max(self.imwidth, self.imheight) / self.__huge_size if self.__huge else 1.0 self.__curr_img = 0 # current image from the pyramid self.__scale = self.imscale * self.__ratio # image pyramide scale self.__reduction = 2 # reduction degree of image pyramid w, h = self.__pyramid[-1].size while w > 512 and h > 512: # top pyramid image is around 512 pixels in size w /= self.__reduction # divide on reduction degree h /= self.__reduction # divide on reduction degree self.__pyramid.append(self.__pyramid[-1].resize((int(w), int(h)), self.__filter)) # Put image into container rectangle and use it to set proper coordinates to the image self.container = self.canvas.create_rectangle((0, 0, self.imwidth, self.imheight), width=0) self.__show_image() # show image on the canvas self.canvas.focus_set() # set focus on the canvas def smaller(self): """ Resize image proportionally and return smaller image """ w1, h1 = float(self.imwidth), float(self.imheight) w2, h2 = float(self.__huge_size), float(self.__huge_size) aspect_ratio1 = w1 / h1 aspect_ratio2 = w2 / h2 # it equals to 1.0 if aspect_ratio1 == aspect_ratio2: image = Image.new('RGB', (int(w2), int(h2))) k = h2 / h1 # compression ratio w = int(w2) # band length elif aspect_ratio1 > aspect_ratio2: image = Image.new('RGB', (int(w2), int(w2 / aspect_ratio1))) k = h2 / w1 # compression ratio w = int(w2) # band length else: # aspect_ratio1 < aspect_ration2 image = Image.new('RGB', (int(h2 * aspect_ratio1), int(h2))) k = h2 / h1 # compression ratio w = int(h2 * aspect_ratio1) # band length i, j, n = 0, 1, round(0.5 + self.imheight / self.__band_width) while i < self.imheight: print(' Opening image: {j} from {n}'.format(j=j, n=n), end='') band = min(self.__band_width, self.imheight - i) # width of the tile band self.__tile[1][3] = band # set band width self.__tile[2] = self.__offset + self.imwidth * i * 3 # tile offset (3 bytes per pixel) self.__image.close() self.__image = Image.open(self.path) # reopen / reset image self.__image.size = (self.imwidth, band) # set size of the tile band self.__image.tile = [self.__tile] # set tile cropped = self.__image.crop((0, 0, self.imwidth, band)) # crop tile band image.paste(cropped.resize((w, int(band * k)+1), self.__filter), (0, int(i * k))) i += band j += 1 print(' ' + 30*' ' + ' ', end='') # hide printed string return image def redraw_figures(self): """ Dummy function to redraw figures in the children classes """ pass def grid(self, **kw): """ Put CanvasImage widget on the parent widget """ self.__imframe.grid(**kw) # place CanvasImage widget on the grid self.__imframe.grid(sticky='nswe') # make frame container sticky self.__imframe.rowconfigure(0, weight=1) # make canvas expandable self.__imframe.columnconfigure(0, weight=1) def pack(self, **kw): """ Exception: cannot use pack with this widget """ raise Exception('Cannot use pack with the widget ' + self.__class__.__name__) def place(self, **kw): """ Exception: cannot use place with this widget """ raise Exception('Cannot use place with the widget ' + self.__class__.__name__) # noinspection PyUnusedLocal def __scroll_x(self, *args, **kwargs): """ Scroll canvas horizontally and redraw the image """ self.canvas.xview(*args) # scroll horizontally self.__show_image() # redraw the image # noinspection PyUnusedLocal def __scroll_y(self, *args, **kwargs): """ Scroll canvas vertically and redraw the image """ self.canvas.yview(*args) # scroll vertically self.__show_image() # redraw the image def __show_image(self): """ Show image on the Canvas. Implements correct image zoom almost like in Google Maps """ box_image = self.canvas.coords(self.container) # get image area box_canvas = (self.canvas.canvasx(0), # get visible area of the canvas self.canvas.canvasy(0), self.canvas.canvasx(self.canvas.winfo_width()), self.canvas.canvasy(self.canvas.winfo_height())) box_img_int = tuple(map(int, box_image)) # convert to integer or it will not work properly # Get scroll region box box_scroll = [min(box_img_int[0], box_canvas[0]), min(box_img_int[1], box_canvas[1]), max(box_img_int[2], box_canvas[2]), max(box_img_int[3], box_canvas[3])] # Horizontal part of the image is in the visible area if box_scroll[0] == box_canvas[0] and box_scroll[2] == box_canvas[2]: box_scroll[0] = box_img_int[0] box_scroll[2] = box_img_int[2] # Vertical part of the image is in the visible area if box_scroll[1] == box_canvas[1] and box_scroll[3] == box_canvas[3]: box_scroll[1] = box_img_int[1] box_scroll[3] = box_img_int[3] # Convert scroll region to tuple and to integer self.canvas.configure(scrollregion=tuple(map(int, box_scroll))) # set scroll region x1 = max(box_canvas[0] - box_image[0], 0) # get coordinates (x1,y1,x2,y2) of the image tile y1 = max(box_canvas[1] - box_image[1], 0) x2 = min(box_canvas[2], box_image[2]) - box_image[0] y2 = min(box_canvas[3], box_image[3]) - box_image[1] if int(x2 - x1) > 0 and int(y2 - y1) > 0: # show image if it in the visible area if self.__huge and self.__curr_img < 0: # show huge image h = int((y2 - y1) / self.imscale) # height of the tile band self.__tile[1][3] = h # set the tile band height self.__tile[2] = self.__offset + self.imwidth * int(y1 / self.imscale) * 3 self.__image.close() self.__image = Image.open(self.path) # reopen / reset image self.__image.size = (self.imwidth, h) # set size of the tile band self.__image.tile = [self.__tile] image = self.__image.crop((int(x1 / self.imscale), 0, int(x2 / self.imscale), h)) else: # show normal image image = self.__pyramid[max(0, self.__curr_img)].crop( # crop current img from pyramid (int(x1 / self.__scale), int(y1 / self.__scale), int(x2 / self.__scale), int(y2 / self.__scale))) # imagetk = ImageTk.PhotoImage(image.resize((int(x2 - x1), int(y2 - y1)), self.__filter)) imageid = self.canvas.create_image(max(box_canvas[0], box_img_int[0]), max(box_canvas[1], box_img_int[1]), anchor='nw', image=imagetk) self.canvas.lower(imageid) # set image into background self.canvas.imagetk = imagetk # keep an extra reference to prevent garbage-collection def __move_from(self, event): """ Remember previous coordinates for scrolling with the mouse """ self.canvas.scan_mark(event.x, event.y) def __move_to(self, event): """ Drag (move) canvas to the new position """ self.canvas.scan_dragto(event.x, event.y, gain=1) self.__show_image() # zoom tile and show it on the canvas def outside(self, x, y): """ Checks if the point (x,y) is outside the image area """ bbox = self.canvas.coords(self.container) # get image area if bbox[0] < x < bbox[2] and bbox[1] < y < bbox[3]: return False # point (x,y) is inside the image area else: return True # point (x,y) is outside the image area def __wheel(self, event): """ Zoom with mouse wheel """ x = self.canvas.canvasx(event.x) # get coordinates of the event on the canvas y = self.canvas.canvasy(event.y) if self.outside(x, y): return # zoom only inside image area scale = 1.0 # Respond to Linux (event.num) or Windows (event.delta) wheel event if event.num == 5 or event.delta == -120: # scroll down, smaller if round(self.__min_side * self.imscale) < 30: return # image is less than 30 pixels self.imscale /= self.__delta scale /= self.__delta if event.num == 4 or event.delta == 120: # scroll up, bigger i = min(self.canvas.winfo_width(), self.canvas.winfo_height()) >> 1 if i < self.imscale: return # 1 pixel is bigger than the visible area self.imscale *= self.__delta scale *= self.__delta # Take appropriate image from the pyramid k = self.imscale * self.__ratio # temporary coefficient self.__curr_img = min((-1) * int(math.log(k, self.__reduction)), len(self.__pyramid) - 1) self.__scale = k * math.pow(self.__reduction, max(0, self.__curr_img)) # self.canvas.scale('all', x, y, scale, scale) # rescale all objects # Redraw some figures before showing image on the screen self.redraw_figures() # method for child classes self.__show_image() def __keystroke(self, event): """ Scrolling with the keyboard. Independent from the language of the keyboard, CapsLock, <Ctrl>+<key>, etc. """ if event.state - self.__previous_state == 4: # means that the Control key is pressed pass # do nothing if Control key is pressed else: self.__previous_state = event.state # remember the last keystroke state # Up, Down, Left, Right keystrokes if event.keycode in [68, 39, 102]: # scroll right: keys 'D', 'Right' or 'Numpad-6' self.__scroll_x('scroll', 1, 'unit', event=event) elif event.keycode in [65, 37, 100]: # scroll left: keys 'A', 'Left' or 'Numpad-4' self.__scroll_x('scroll', -1, 'unit', event=event) elif event.keycode in [87, 38, 104]: # scroll up: keys 'W', 'Up' or 'Numpad-8' self.__scroll_y('scroll', -1, 'unit', event=event) elif event.keycode in [83, 40, 98]: # scroll down: keys 'S', 'Down' or 'Numpad-2' self.__scroll_y('scroll', 1, 'unit', event=event) def crop(self, bbox): """ Crop rectangle from the image and return it """ if self.__huge: # image is huge and not totally in RAM band = bbox[3] - bbox[1] # width of the tile band self.__tile[1][3] = band # set the tile height self.__tile[2] = self.__offset + self.imwidth * bbox[1] * 3 # set offset of the band self.__image.close() self.__image = Image.open(self.path) # reopen / reset image self.__image.size = (self.imwidth, band) # set size of the tile band self.__image.tile = [self.__tile] return self.__image.crop((bbox[0], 0, bbox[2], band)) else: # image is totally in RAM return self.__pyramid[0].crop(bbox) def destroy(self): """ ImageFrame destructor """ self.__image.close() map(lambda i: i.close, self.__pyramid) # close all pyramid images del self.__pyramid[:] # delete pyramid list del self.__pyramid # delete pyramid variable self.canvas.destroy() self.__imframe.destroy() class MainWindow(ttk.Frame): """ Main window class """ def __init__(self, mainframe, path): """ Initialize the main Frame """ ttk.Frame.__init__(self, master=mainframe) self.master.title('Advanced Zoom v3.0') self.master.geometry('800x600') # size of the main window self.master.rowconfigure(0, weight=1) # make the CanvasImage widget expandable self.master.columnconfigure(0, weight=1) canvas = CanvasImage(self.master, path) # create widget canvas.grid(row=0, column=0) # show widget filename = './data/img_plg5.png' # place path to your image here #filename = 'd:/Data/yandex_z18_1-1.tif' # huge TIFF file 1.4 GB #filename = 'd:/Data/The_Garden_of_Earthly_Delights_by_Bosch_High_Resolution.jpg' #filename = 'd:/Data/The_Garden_of_Earthly_Delights_by_Bosch_High_Resolution.tif' #filename = 'd:/Data/heic1502a.tif' #filename = 'd:/Data/land_shallow_topo_east.tif' #filename = 'd:/Data/X1D5_B0002594.3FR' app = MainWindow(tk.Tk(), path=filename) app.mainloop()P.S. Here is the GitHub application using advanced zoom for manual image annotation with polygons.
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