I am trying to write a code that would place a point/line/whatever at the mouse coordinates, aka Paint. I am using PIL and Tkinter. The problem is I can't understand how to realise canvas update.
window = Tk(className ='Window')
image = Image.new('RGB', (800,600),"#ffffff")
image_tk = PhotoImage(image)
canvas = Canvas(window,width = 800, height = 600)
canvas.create_image(400 ,300,image = image_tk)
canvas.pack()
draw = ImageDraw.Draw(image)
def mouseclick(event):
draw.point((event.x,event.y),fill=128)
print event.x,event.y
canvas.bind("<Button-1>", mouseclick)
mainloop()
What should be added? Maybe there are other better modules for doing it ?
That is going to be expensive, you need to create a new PhotoImage to reflect your modifications. Alternatively, consider drawing to the canvas without using an image. If you then need to save what was draw in the canvas you have the easy option to export it to postscript, or the harder option of storing what was drawn and reproducing it.
For the moment, here is an example that adjusts your code so it works as you intended (although I recommend the option of drawing in the canvas):
import Tkinter
from PIL import Image, ImageDraw, ImageTk
def paint_img(event, canvas):
x, y = event.x, event.y
image_draw.ellipse((x-5, y-5, x+5, y+5), fill='black')
canvas._image_tk = ImageTk.PhotoImage(image)
canvas.itemconfigure(canvas._image_id, image=canvas._image_tk)
root = Tkinter.Tk()
width, height = 800, 600
canvas = Tkinter.Canvas(width=width, height=height)
canvas.pack()
image = Image.new('RGB', (width, height), '#cdcdcd')
image_draw = ImageDraw.Draw(image)
canvas._image_tk = ImageTk.PhotoImage(image)
canvas._image_id = canvas.create_image(0, 0, image=canvas._image_tk, anchor='nw')
canvas.tag_bind(canvas._image_id, "<Button-1>", lambda e: paint_img(e, canvas))
root.mainloop()
Related
from Tkinter import *
root = Tk()
cv = Canvas(root)
cv.create_rectangle(10,10,50,50)
cv.pack()
root.mainloop()
I want to convert canvas content to a bitmap or other image, and then do other operations, such as rotating or scaling the image, or changing its coordinates.
Bitmaps can improve efficiency to show if I am no longer drawing.
What should I do?
You can either generate a postscript document (to feed into some other tool: ImageMagick, Ghostscript, etc):
from Tkinter import *
root = Tk()
cv = Canvas(root)
cv.create_rectangle(10,10,50,50)
cv.pack()
root.mainloop()
cv.update()
cv.postscript(file="file_name.ps", colormode='color')
root.mainloop()
or draw the same image in parallel on PIL and on Tkinter's canvas (see: Saving a Tkinter Canvas Drawing (Python)). For example (inspired by the same article):
from Tkinter import *
import Image, ImageDraw
width = 400
height = 300
center = height//2
white = (255, 255, 255)
green = (0,128,0)
root = Tk()
# Tkinter create a canvas to draw on
cv = Canvas(root, width=width, height=height, bg='white')
cv.pack()
# PIL create an empty image and draw object to draw on
# memory only, not visible
image1 = Image.new("RGB", (width, height), white)
draw = ImageDraw.Draw(image1)
# do the Tkinter canvas drawings (visible)
cv.create_line([0, center, width, center], fill='green')
# do the PIL image/draw (in memory) drawings
draw.line([0, center, width, center], green)
# PIL image can be saved as .png .jpg .gif or .bmp file (among others)
filename = "my_drawing.jpg"
image1.save(filename)
root.mainloop()
I have found a great way of doing this which is really helpful. For it, you need the PIL module. Here is the code:
from PIL import ImageGrab
def getter(widget):
x=root.winfo_rootx()+widget.winfo_x()
y=root.winfo_rooty()+widget.winfo_y()
x1=x+widget.winfo_width()
y1=y+widget.winfo_height()
ImageGrab.grab().crop((x,y,x1,y1)).save("file path here")
What this does is you pass a widget name into the function. The command root.winfo_rootx() and the root.winfo_rooty() get the pixel position of the top left of the overall root window.
Then, the widget.winfo_x() and widget.winfo_y() are added to, basically just get the pixel coordinate of the top left hand pixel of the widget which you want to capture (at pixels (x,y) of your screen).
I then find the (x1,y1) which is the bottom left pixel of the widget. The ImageGrab.grab() makes a printscreen, and I then crop it to only get the bit containing the widget. Although not perfect, and won't make the best possible image, this is a great tool for just getting a image of any widget and saving it.
If you have any questions, post a comment! Hope this helped!
Use Pillow to convert from Postscript to PNG
from PIL import Image
def save_as_png(canvas,fileName):
# save postscipt image
canvas.postscript(file = fileName + '.eps')
# use PIL to convert to PNG
img = Image.open(fileName + '.eps')
img.save(fileName + '.png', 'png')
Maybe you can try to use widget_winfo_id to get the HWND of the canvas.
import win32gui
from PIL import ImageGrab
HWND = canvas.winfo_id() # get the handle of the canvas
rect = win32gui.GetWindowRect(HWND) # get the coordinate of the canvas
im = ImageGrab.grab(rect) # get image of the current location
A better way for #B.Jenkins's answer that doesn't need a reference to the root object:
from PIL import ImageGrab
def save_widget_as_image(widget, file_name):
ImageGrab.grab(bbox=(
widget.winfo_rootx(),
widget.winfo_rooty(),
widget.winfo_rootx() + widget.winfo_width(),
widget.winfo_rooty() + widget.winfo_height()
)).save(file_name)
On my system had serious issues with ghostscript and the ImageGrab in general. Solution draw on PIL Image, save as a file, load file on PhotoImage, which is used to create new TKinter Canvas.
canvas = Canvas(win, width=IMG_W, height=IMG_H)
img = PILImg.new("RGB", (IMG_W, IMG_H), "#000")
draw = ImageDraw.Draw(img)
draw.rectangle([x,y,w,h], fill=color, outline=border)
img.save("stock-chart.png")
copyImg = PhotoImage(file="stock-chart.png")
canvas.create_image(IMG_W_2, IMG_H_2, image=copyImg)
I´m designing a slideshow with no user intervention, where:
a. Every image is generated by the Python script itself
b. There´s no file saving, for performance reasons
c. Every image is shown in fullscreen for a certain time
d. It´s a loop that´s supposed to never end. There´s always going to be an image to show
So far, by adapting code found in a few pages, I have it running. But every image is shown for X time and then the desktop background appears for a second or so.
I´d like to have a smooth switching from one file to next, such as FEH does. As a matter of fact, I´m trying to replace FEH because I need finer control of the display of each file (for instance, changing the time it appears on screen).
Here´s my code:
from PIL import Image
from PIL import ImageFont
from PIL import ImageDraw
from PIL import ImageTk
import tkinter
def show_center(pil_image, msDelay):
root = tkinter.Tk()
w, h = root.winfo_screenwidth(), root.winfo_screenheight()
root.overrideredirect(1)
root.geometry("%dx%d+0+0" % (w, h))
root.focus_set()
root.attributes("-topmost", True)
canvas = tkinter.Canvas(root, width=w, height=h, highlightthickness=0)
canvas.pack()
canvas.configure(background='black')
image = ImageTk.PhotoImage(pil_image)
imagesprite = canvas.create_image(w / 2, h / 2, image=image)
root.after(msDelay, root.destroy)
root.mainloop()
### script body
while True:
# loads common background image
img = Image.open(baseImage)
draw = ImageDraw.Draw(img)
# here: image customization
draw.rectangle(....)
draw.text(....)
img.paste(....)
# shows this file
thisDelay = some Number Calculation
show_center(img, thisDelay)
Any ideas on how to avoid the desktop appearing between images? This will run in a headless Raspberry. I´m using Python3 on Raspbian.
Thanks in advance!
You can use after() instead of the while loop and simply use Label instead of Canvas:
import tkinter as tk
from PIL import Image, ImageTk, ImageDraw, ImageFont
import time
import random
def update_image():
# sample drawing
image = base_image.copy()
draw = ImageDraw.Draw(image)
draw.rectangle((100, 100, 500, 400), outline=random.choice(('red', 'green', 'blue', 'magenta', 'gold', 'orange')))
draw.text((120, 120), f"""{time.strftime("%F %T")}""")
# update image
tkimg = ImageTk.PhotoImage(image)
label.config(image=tkimg)
label.image = tkimg # save a reference to avoid garbage collected
ms_delay = random.randint(1000, 9000) # sample delay calculation
root.after(ms_delay, update_image)
root = tk.Tk()
root.attributes("-fullscreen", 1, "-topmost", 1)
base_image = Image.open("/path/to/base/image")
# label for showing image
label = tk.Label(root, bg="black")
label.pack(fill="both", expand=1)
update_image() # start the slide show
root.mainloop()
Well, it´s working quite well.
The solution required a bit of logic (maybe it makes sense not to destroy the object for every image) and a bit of good old trial & error.
The changes were:
Init the canvas only once, use global vars to make it persistent
For every image, call the display function and keep calling root.update() until the required timeout is reached
So, the prior function gets divided, and it looks like:
global canvas, root
global w, h
def init_image():
global canvas, root
global w, h
root = tkinter.Tk()
w, h = root.winfo_screenwidth(), root.winfo_screenheight()
root.overrideredirect(1)
root.geometry("%dx%d+0+0" % (w, h))
root.focus_set()
root.attributes("-topmost", True)
canvas = tkinter.Canvas(root, width=w, height=h, highlightthickness=0)
canvas.pack()
canvas.configure(background='black')
return
def show_center(pil_image, msDelay):
global canvas, root
global w, h
image = ImageTk.PhotoImage(pil_image)
imagesprite = canvas.create_image(w / 2, h / 2, image=image)
inicio = int(time.time() * 1000)
while 1:
root.update()
if (int(time.time() * 1000) - inicio) > msDelay:
break
return
Function init_image() is called once at beginning, and function show_center() is called for every image as the original post.
I hope this can be useful to anybody trying to accomplish the same.
I can't display images longer (height) than about 30612 pixels high. I've read that there is a maximum height to canvas. I'd like to get the source file and extend that to 90 or 100k pixels in height. Conversely, I've seen suggested that a canvas may be buffered, if this is true, I have no clue how to implement it.. Any help is appreciated!
I am using code I found off Stack that is supposed to deal with large images, it does alright, but ultimately hit's the cavas height limit.
Canvas Limit
from tkinter import *
from PIL import ImageTk
from PIL import *
Image.MAX_IMAGE_PIXELS = None
class ScrolledCanvas(Frame):
def __init__(self, parent=None):
Frame.__init__(self, parent)
self.master.title("Spectrogram Viewer")
self.pack(expand=YES, fill=BOTH)
canv = Canvas(self, relief=SUNKEN)
canv.config(width=400, height=500)
# canv.config(scrollregion=(0,0,1000, 1000))
# canv.configure(scrollregion=canv.bbox('all'))
canv.config(highlightthickness=0)
sbarV = Scrollbar(self, orient=VERTICAL)
sbarH = Scrollbar(self, orient=HORIZONTAL)
sbarV.config(command=canv.yview)
sbarH.config(command=canv.xview)
canv.config(yscrollcommand=sbarV.set)
canv.config(xscrollcommand=sbarH.set)
sbarV.pack(side=RIGHT, fill=Y)
sbarH.pack(side=BOTTOM, fill=X)
canv.pack(side=LEFT, expand=YES, fill=BOTH)
self.im = Image.open("Test_3.tif")
width, height = self.im.size
canv.config(scrollregion=(0, 0, width, height))
self.im2 = ImageTk.PhotoImage(self.im)
self.imgtag = canv.create_image(0, 0, anchor="nw", image=self.im2)
ScrolledCanvas().mainloop()
I tried to put together a bigger image from displays of a grid of canvases. This looks like it might work, at least if you just want to display a big image. I have just tested with a small image and not paid any attention to memory or speed or anything...
from tkinter import *
from scrframe import VerticalScrolledFrame
root = Tk()
tiles = VerticalScrolledFrame(root) # Scrolled frame
tiles.grid()
tw = 90 # Tile width
th = 110 # Tile height
rows = 4 # Number of tiles/row
cols = 4 # Number of tiles/column
tile_list = [] # List of image tiles
img = PhotoImage(file='pilner.png')
for r in range(rows):
col_list = []
for c in range(cols):
tile = Canvas(tiles.interior, highlightthickness=0, bg='tan1',
width=tw, height=th)
tile.create_image(-c*tw, -r*th, image=img, anchor ='nw')
tile.grid(row=r, column=c)
col_list.append(tile)
tile_list.append(col_list)
root.mainloop()
Now, scrolling a frame seems to raise some problems, but there also seems to be solutions. I tried to use VerticalScrolledFrame as described in Python Tkinter scrollbar for frame and it works fine. As it only provides for a vertical scrollbar you'd have to implement horizontal scrollbar yourself. Maybe a few additional functions as scrolling with the mouse wheel, keyboard shortcuts or other would be useful.
I got the VerticalScrolledFrame from TKinter scrollable frame and modified it for Python 3.
This is the code I've come up with from several sources - Thanks to figbeam for all the help. Also, this is not pretty!!!! The button shows up in the center of the Tkinter window. If you'd like to modify this, please do.
from tkinter import *
from PIL import ImageTk as itk
from PIL import Image
import math
import numpy as np
Image.MAX_IMAGE_PIXELS = None #prevents the "photo bomb" warning from popping up. Have to have this for really large images.
#----------------------------------------------------------------------
# makes a simple window with a button right in the middle that let's you go "down" an image.
class MainWindow():
#----------------
def __init__(self, main):
# canvas for image
_, th, tw, rows, cols = self.getrowsandcols()
self.canvas = Canvas(main, width=tw, height=th)
self.canvas.grid(row=0, column=0)
# images
self.my_images = self.cropimages() # crop the really large image down into several smaller images and append to this list
self.my_image_number = 0 #
# set first image on canvas
self.image_on_canvas = self.canvas.create_image(0, 0, anchor = NW, image = self.my_images[self.my_image_number])
# button to change image
self.button = Button(main, text="DOWN", command=self.onDownButton)
self.button.grid(row=0, column=0)
#----------------
def getimage(self):
im = Image.open("Test_3.png") # import the image
im = im.convert("RGBA") # convert the image to color including the alpha channel (which is the transparency best I understand)
width, height = im.size # get the width and height
return width, height, im # return relevent variables/objects
def getrowsandcols(self):
width, height, im = self.getimage()
im = np.asarray(im) # Convert image to Numpy Array
tw = width # Tile width will equal the width of the image
th = int(math.ceil(height / 100)) # Tile height
rows = int(math.ceil(height / th)) # Number of tiles/row
cols = int(math.ceil(width / tw)) # Number of tiles/column
return im, th, tw, rows, cols #return selected variables
def cropimages(self):
self.my_images = [] # initialize list to hold Tkinter "PhotoImage objects"
im, th, tw, rows, cols = self.getrowsandcols() # pull in needed variables to crop the really long image
for r in range(rows): # loop row by row to crop all of the image
crop_im =im[r * th:((r * th) + th), 0:tw] # crop the image for the current row (r). (th) stands for tile height.
crop_im = Image.fromarray(crop_im) # convert the image from an Numpy Array to a PIL image.
crop_im = itk.PhotoImage(crop_im) # convert the PIL image to a Tkinter Photo Object (whatever that is)
self.my_images.append(crop_im) # Append the photo object to the list
crop_im = None
return self.my_images
def onDownButton(self):
# next image
self.my_image_number += 1 #every button pressed will
# return to first image
if self.my_image_number == len(self.my_images):
self.my_image_number = 0
# change image
self.canvas.itemconfig(self.image_on_canvas, image = self.my_images[self.my_image_number]) #attaches the image from the image list to the canvas
#----------------------------------------------------------------------
root = Tk()
MainWindow(root)
root.mainloop()
I want to draw an image programmatically. Essentially I am talking about setting each single pixel as a map of the image, and I would like to do that using PIL/pillow. Then, I would like to display it on the screen. The GUI is based on TKinter.
root = Tk()
root.wm_title("Lands - A world generator")
root.resizable(0,0)
prepare_menu()
canvas = Canvas(root, width=canvas_width, height=canvas_height)
canvas.pack()
root.mainloop()
The prepare_menu sets the menu and associates one entry with an event handler, which calls the function show_elevation_map like this:
def show_elevation_map(p, width, height):
hm = platec.get_heightmap(p)
img = PIL.Image.new('RGBA', (width, height))
pixels = img.load()
for y in range(0, height):
for x in range(0, width):
pixels[x, y] = (255, 0, 0, 255)
pi = ImageTk.PhotoImage(img)
sprite = canvas.create_image(100, 100, image=pi)
canvas.update()
I tried it like this, but I cannot see anything on the screen, while I would expect to see everything red. What am I doing wrong here?
Thanks.
Your image is likely getting garbage collected. You need to save a persistent reference to the image.
Trying to set up a background for my tkinter window. I have a square background image, which fades to black around the edges, and then the main window has a black background. The image is placed over the background, and if the window is wider than it is tall, the image centers itself in the middle over the black background, and it all looks very nice.
However when the window is smaller than the image in width and height, it puts the center of the image in the center of the window, so you don't see the whole image, and it looks a little odd. Is there a way of resizing the image so that if the largest of the width and height of the window is smaller than the image, the image is adjusted to that size, keeping aspect ratio.
So say the background image is 600x600:
In a 800x400 window, the image does not resize, and centers itself vertically.
In a 500x400 window, the image resizes to 500x500, and still centers itself vertically.
In a 400x900 window, the image does not resize, and centers itself horizontally.
The centering functionality is already there, I just need the resize functionality.
Currently what I have is:
from tkinter import *
root = Tk()
root.title("Title")
root.geometry("600x600")
root.configure(background="black")
background_image = PhotoImage(file="Background.gif")
background = Label(root, image=background_image, bd=0)
background.pack()
root.mainloop()
Not sure if there is a way of doing this in tkinter? Or if perhaps I would write my own function that resizes the image according to the window size, however the image needs to resize relatively smoothly and quickly if the user resizes the window at any point.
This is example application that uses Pillow to resize image on the Label as the label changes size:
from tkinter import *
from PIL import Image, ImageTk
root = Tk()
root.title("Title")
root.geometry("600x600")
root.configure(background="black")
class Example(Frame):
def __init__(self, master, *pargs):
Frame.__init__(self, master, *pargs)
self.image = Image.open("./resource/Background.gif")
self.img_copy= self.image.copy()
self.background_image = ImageTk.PhotoImage(self.image)
self.background = Label(self, image=self.background_image)
self.background.pack(fill=BOTH, expand=YES)
self.background.bind('<Configure>', self._resize_image)
def _resize_image(self,event):
new_width = event.width
new_height = event.height
self.image = self.img_copy.resize((new_width, new_height))
self.background_image = ImageTk.PhotoImage(self.image)
self.background.configure(image = self.background_image)
e = Example(root)
e.pack(fill=BOTH, expand=YES)
root.mainloop()
This is how it works using Lenna image as example:
I have modified the above code so it is not in a class
#!/usr/bin/python3.5
from tkinter import *
from tkinter import ttk
from PIL import Image, ImageTk
root = Tk()
root.title("Title")
root.geometry('600x600')
def resize_image(event):
new_width = event.width
new_height = event.height
image = copy_of_image.resize((new_width, new_height))
photo = ImageTk.PhotoImage(image)
label.config(image = photo)
label.image = photo #avoid garbage collection
image = Image.open('image.gif')
copy_of_image = image.copy()
photo = ImageTk.PhotoImage(image)
label = ttk.Label(root, image = photo)
label.bind('<Configure>', resize_image)
label.pack(fill=BOTH, expand = YES)
root.mainloop()
Just sugesting a slight change in the answer. Using self.master.winfo_width(),self.master.winfo_height() instead of 'event' makes he adjustment to size much quicker.
import tkinter as tk
from PIL import Image, ImageTk
class Layout:
def __init__(self,master):
self.master = master
self.rootgeometry()
self.canvas = tk.Canvas(self.master)
self.canvas.pack()
self.background_image = Image.open('image_file.PNG')
self.image_copy = self.background_image.copy()
self.background = ImageTk.PhotoImage(self.background_image)
self.loadbackground()
def loadbackground(self):
self.label = tk.Label(self.canvas, image = self.background)
self.label.bind('<Configure>',self.resizeimage)
self.label.pack(fill='both', expand='yes')
def rootgeometry(self):
x=int(self.master.winfo_screenwidth()*0.7)
y=int(self.master.winfo_screenheight()*0.7)
z = str(x) +'x'+str(y)
self.master.geometry(z)
def resizeimage(self,event):
image = self.image_copy.resize((self.master.winfo_width(),self.master.winfo_height()))
self.image1 = ImageTk.PhotoImage(image)
self.label.config(image = self.image1)
root = tk.Tk()
a = Styling.Layout(root)
root.mainloop()
i have created function for calling resize a single time with methods after et after cancel
def on_resize(self, evt):
if self.inter == 0:
self.inter = 1
self.minuteur = self.fenetrePrincipale.after(100, self.endResize)
else:
self.minuteur = self.fenetrePrincipale.after_cancel(self.minuteur)
self.minuteur = self.fenetrePrincipale.after(100, self.endResize)
def endResize(self):
self.inter = 0
self.fenetrePrincipale.background = self.fenetrePrincipale.background.resize((self.fenetrePrincipale.winfo_width(), self.fenetrePrincipale.winfo_height()))
self.pixi = ImageTk.PhotoImage(self.fenetrePrincipale.background)
self.canvas.configure(width=self.fenetrePrincipale.winfo_width(), height=self.fenetrePrincipale.winfo_height())
self.canvas.create_image(0, 0, anchor=NW, image=self.pixi)
Here is the principle, after defines a timer and a function to be recalled at the end, after_cancel cleans the timer so each iteration of the function cleans the timer and starts it, at the last iteration of resize the timer remains triggered.
for more information on cancel and timer with after:
after detailled