how to do automatic image resizing in Python3 with PyGI? - image

Although I have found partial and indirect answers to this question (see, e.g., this link), I am posting this here because putting together the bits and pieces of the puzzle took me a bit of time, and I thought someone else might find my efforts of use.
So, how to achieve a seamless resizing of images on buttons in GTK+ when the parent window is resized?

The solution offered for PyGTK in the link posted in the question does not work in Python-GI with GTK3, although the trick of using a ScrolledWindow in place of the usual Box was very useful.
Here is my minimal working solution to getting an image on a button to resize with the container.
from gi.repository import Gtk, Gdk, GdkPixbuf
class ButtonWindow(Gtk.Window):
def __init__(self):
Gtk.Window.__init__(self, title="Button Demo")
self.set_border_width(10)
self.connect("delete-event", Gtk.main_quit)
self.connect("check_resize", self.on_check_resize)
self.box = Gtk.ScrolledWindow()
self.box.set_policy(Gtk.PolicyType.ALWAYS,
Gtk.PolicyType.ALWAYS)
self.add(self.box)
self.click = Gtk.Button()
self.box.add_with_viewport(self.click)
self.pixbuf = GdkPixbuf.Pixbuf().new_from_file('gtk-logo-rgb.jpg')
self.image = Gtk.Image().new_from_pixbuf(self.pixbuf)
self.click.add(self.image)
def resizeImage(self, x, y):
print('Resizing Image to ('+str(x)+','+str(y)+')....')
pixbuf = self.pixbuf.scale_simple(x, y,
GdkPixbuf.InterpType.BILINEAR)
self.image.set_from_pixbuf(pixbuf)
def on_check_resize(self, window):
print("Checking resize....")
boxAllocation = self.box.get_allocation()
self.click.set_allocation(boxAllocation)
self.resizeImage(boxAllocation.width-10,
boxAllocation.height-10)
win = ButtonWindow()
win.show_all()
Gtk.main()
(The -10 on the width and height are to accommodate the inner borders and padding in the button. I tried fiddling with this to get a bigger image on the button, but the result did not look so nice.)
The jpeg file used in this example can be downloaded from here.
I welcome further suggestions on how to do this.

self.image = Gtk.Image().new_from_pixbuf(self.pixbuf)
Should probably be:
self.image = Gtk.Image().set_from_pixbuf(self.pixbuf)
You're creating a new image twice.

Related

How to handle sprite animation in Kivy

I am coding a game using Kivy. I have a Screen class where I put my animation code. It's not a usual game, it's more like several screens, each with its own animation, with button commands for going back and forth to different screens.
It works ok, but when I make more classes like this and put it all in a ScreenManager, the animation is disrupted with random white screens.
class Pas(Screen):
def __init__(self, **kwargs):
super(Pas, self).__init__(**kwargs)
Clock.schedule_interval(self.update, 1 / 60.0)
self.ani_speed_init = 15
self.ani_speed = self.ani_speed_init
self.ani = glob.glob("img/pas_ani*.png")
self.ani.sort()
self.ani_pos = 0
self.ani_max = len(self.ani)-1
self.img = self.ani[0]
self.update(1)
back = Button(
background_normal=('img/back-icon.png'),
background_down=('img/back-icon.png'),
pos=(380, 420))
self.add_widget(back)
def callback(instance):
sm.current = 'game'
back.bind(on_press=callback)
def update(self, dt):
self.ani_speed -= 1
if self.ani_speed == 0:
self.img = self.ani[self.ani_pos]
self.ani_speed = self.ani_speed_init
if self.ani_pos == self.ani_max:
self.ani_pos = 0
else:
self.ani_pos += 1
with self.canvas:
image = Image(source=self.img, pos=(0, 0), size=(320, 480))
What am I doing wrong? I am also accepting ideas for a different way of doing this.
If you want to use Screen and ScreenManager for your screens, it would be better to use the transition system they define and use, so, to define your own Transitions, and apply them. If you want more control, i would advise getting ride of Screen and ScreenManager, and just using Widgets, to control the whole drawing/positioning process.
Also, Clock.schedule_interval(self.update, 0) is equivalent to the call you are making, the animation will be called each frame, and you can use dt to manage the animation progress.
Also, kivy can manage gifs, as well as zip archives of images to directly do animations (useful to have animated pngs), you can let kivy manage the whole animation process this way.

qwidget.render drawing with offset in QStyledItemDelegate

I'm trying to create a delegate to draw custom widgets as elements in a listview on icon mode. I have it more or less working but I can't get the widgets to draw in the right place, it seems they are getting drawn considering (0,0) the origin on the main window not the origin of the list view. What do I need to pass to render the widget on the right place? I know I can pass an offset... how can I calculate the offset between the main window and the listview?
This is my paint method on my delegate (derived from QStyledItemDelegate)
def paint(self, painter, option, index):
painter.save()
if option.state & QStyle.State_Selected:
painter.fillRect(option.rect, option.palette.highlight());
model = index.model()
myWidget = model.listdata[index.row()]
myWidget.setGeometry(option.rect)
myWidget.render(painter, option.rect.topLeft() )
painter.restore()
Thanks
/J
In case this is useful for someone else I'll post my solution...
I don't know if this is the best way of doing it, but I'm calculating the offset by mapping the orgin of my parent to the main window:
offset = self._parent.mapTo(self._mainWindow, QPoint(0,0))
myWidget.render(painter, option.rect.topLeft() + offset)
It works, so I'll use it until I find a better way for doing this.
You can render your Widget into a temporary pixmap and then draw the pixmap instead. That solves the shift issue:
def paint(self, painter, option, index):
pic = QPixmap( option.rect.width(), option.rect.height() )
w = ItemWidget()
w.setGeometry( option.rect )
w.render(pic)
painter.drawPixmap( option.rect, pic )
I use another alternative method, and it works.
painter.translate(option.rect.topLeft())
myWidget.render(painter, QtCore.QPoint(0, 0))

wxOGL wx.ShapeCanvas images

I am making a small photo editing application using wxPython ogl.ShapeCanvas. I can load images on the canvas. I just want to know how will I adjust the brightness/contrast of an image inside the canvas (using a slider).
Thanks
Hope it's not to late to be of any help, but...I had to do something similar with OGL recently when I wanted to adjust the transparency on the fly. What I ended up doing was creating a class that made the adjustments and returned a wx.Bitmap, then I had a ShapeCanvas subclass use the adjusted picture, e.g.
class PicAdjuster(cls):
def adjust_pic(self, image_filename, factor_red = 1., factor_green = 1., factor_blue = 1., factor_alpha = 1.):
original_img = wx.Image(image_filename)
adjusted_img = original_img.AdjustChannels(factor_red, factor_green, factor_blue, factor_alpha)
return wx.BitmapFromImage(adjusted_img)
then for the ShapeCanvas:
class PicDisplay(ogl.ShapeCanvas):
def add_picture(self, image_filename):
new_img = ogl.BitmapShape()
add_alpha = PicAdjuster()
new_img.SetBitmap(add_alpha.adjust_pic(factor_alpha = 0.5))
self.diagram.AddShape(new_img)
Anyway, you might be able to do something similar to make your adjustments; just use your picture adjuster and call the ogl.BitmapShape's SetBitmap() method as required.

How to Get a Window or Fullscreen Screenshot (without PIL)?

With python 3, I'd like to get a handle to another window (not part of my application) such that I can either:
directly capture that window as a screenshot, or
determine its position and size and capture it some other way
In case it is important, I am using Windows XP (edit: works in Windows 7 also).
I found this solution, but it is not quite what I need since it is full screen and more importantly, PIL to the best of my knowledge does not support 3.x yet.
Here's how you can do it using PIL on win32. Given a window handle (hwnd), you should only need the last 4 lines of code. The preceding simply search for a window with "firefox" in the title. Since PIL's source is available, you should be able to poke around the ImageGrab.grab(bbox) method and figure out the win32 code you need to make this happen.
from PIL import ImageGrab
import win32gui
toplist, winlist = [], []
def enum_cb(hwnd, results):
winlist.append((hwnd, win32gui.GetWindowText(hwnd)))
win32gui.EnumWindows(enum_cb, toplist)
firefox = [(hwnd, title) for hwnd, title in winlist if 'firefox' in title.lower()]
# just grab the hwnd for first window matching firefox
firefox = firefox[0]
hwnd = firefox[0]
win32gui.SetForegroundWindow(hwnd)
bbox = win32gui.GetWindowRect(hwnd)
img = ImageGrab.grab(bbox)
img.show()
Ars gave me all the pieces. I am just putting the pieces together here for anyone else who needs to get a screenshot in python 3.x. Next I need to figure out how to work with a win32 bitmap without having PIL to lean on.
Get a Screenshot (pass hwnd for a window instead of full screen):
def screenshot(hwnd = None):
import win32gui
import win32ui
import win32con
from time import sleep
if not hwnd:
hwnd=win32gui.GetDesktopWindow()
l,t,r,b=win32gui.GetWindowRect(hwnd)
h=b-t
w=r-l
hDC = win32gui.GetWindowDC(hwnd)
myDC=win32ui.CreateDCFromHandle(hDC)
newDC=myDC.CreateCompatibleDC()
myBitMap = win32ui.CreateBitmap()
myBitMap.CreateCompatibleBitmap(myDC, w, h)
newDC.SelectObject(myBitMap)
win32gui.SetForegroundWindow(hwnd)
sleep(.2) #lame way to allow screen to draw before taking shot
newDC.BitBlt((0,0),(w, h) , myDC, (0,0), win32con.SRCCOPY)
myBitMap.Paint(newDC)
myBitMap.SaveBitmapFile(newDC,'c:\\tmp.bmp')
Get a Window Handle by title (to pass to the above function):
def _get_windows_bytitle(title_text, exact = False):
def _window_callback(hwnd, all_windows):
all_windows.append((hwnd, win32gui.GetWindowText(hwnd)))
windows = []
win32gui.EnumWindows(_window_callback, windows)
if exact:
return [hwnd for hwnd, title in windows if title_text == title]
else:
return [hwnd for hwnd, title in windows if title_text in title]
This will take a new opened window and make a screenshot of it and then crop it with PIL also possible to find your specific window with pygetwindow.getAllTitles() and then fill in your window name in z3 to get screenshot of only that window.
If you definitely not want to use PIL you can maximize window with pygetwindow module and then make a screenshot with pyautogui module.
Note: not tested on Windows XP (but tested on Windows 10)
import pygetwindow
import time
import os
import pyautogui
import PIL
# get screensize
x,y = pyautogui.size()
print(f"width={x}\theight={y}")
x2,y2 = pyautogui.size()
x2,y2=int(str(x2)),int(str(y2))
print(x2//2)
print(y2//2)
# find new window title
z1 = pygetwindow.getAllTitles()
time.sleep(1)
print(len(z1))
# test with pictures folder
os.startfile("C:\\Users\\yourname\\Pictures")
time.sleep(1)
z2 = pygetwindow.getAllTitles()
print(len(z2))
time.sleep(1)
z3 = [x for x in z2 if x not in z1]
z3 = ''.join(z3)
time.sleep(3)
# also able to edit z3 to specified window-title string like: "Sublime Text (UNREGISTERED)"
my = pygetwindow.getWindowsWithTitle(z3)[0]
# quarter of screen screensize
x3 = x2 // 2
y3 = y2 // 2
my.resizeTo(x3,y3)
# top-left
my.moveTo(0, 0)
time.sleep(3)
my.activate()
time.sleep(1)
# save screenshot
p = pyautogui.screenshot()
p.save(r'C:\\Users\\yourname\\Pictures\\\\p.png')
# edit screenshot
im = PIL.Image.open('C:\\Users\\yourname\\Pictures\\p.png')
im_crop = im.crop((0, 0, x3, y3))
im_crop.save('C:\\Users\\yourname\\Pictures\\p.jpg', quality=100)
# close window
time.sleep(1)
my.close()
The solution here gets a screenshot of a single Window (so can work if the Window is in the background).
Other solutions of this page take picture of the part of the screen the window is on, and thus need to bring the Window to the front first.
Python Screenshot of inactive window PrintWindow + win32gui

Python 3.1 Tkinter layout help. I am close, please help me finish this

I am using Python 3.1 by the way.
I am trying to build a simple GUI using Tkinter - label, text entry field, button on the first row and editable text area with scrollbar to the right and on the bottom of it - on the second row. Please help me fix up the layout. What I have below does not quite work. If I have to use a grid, I will. I wish to keep the code very simple - I want to "sell" Python to some of my coworkers. So, I want to get a somewhat decent look and feel. Suggest better padding if you do not mind. Also, if my variable names, etc. seem weird, then please make a note.
At the same time I want to pretend that this is a throw-away script which I have not spent much time on. Since I am asking for your help, it ain't so, but they do not need to know ;). So, I do not want to introduce fancy code to create nice borders, etc. I just want something that is visually appealing, clean and simple. If I do not, then my presentation will not achieve its goal.
Thank you, my code is below:
class App:
def __init__(self, parent):
frame = Frame(parent)
self.__setup_gui(frame) # Call Helper
frame.pack(padx=15, pady=15)
parent.title('To be changed')
def __setup_gui(self, frame):
# First Row
self.cs_label = Label(frame, text='Change Set: ')
self.cs_label.pack(side=LEFT, padx=10, pady=10)
self.cs_val = Entry(frame, width=10)
self.cs_val.pack(side=LEFT, padx=10, pady=10)
self.get_button = Button(frame, text='Get', command=self.get_content)
self.get_button.pack(side=LEFT, padx=10, pady=10)
# Text area and scrollbar
self.text_area = Text(frame, height=10, width=50, background='white')
# Put a scroll bar in the frame
scroll = Scrollbar(frame)
self.text_area.configure(yscrollcommand=scroll.set)
self.text_area.pack(side=TOP)
scroll.pack(side=RIGHT,fill=Y)
self.clipboard_var = IntVar()
self.notepad_var = IntVar()
def get_content(self):
print(self.clipboard_var.get())
print(self.notepad_var.get())
###################################################################################################
if __name__ == '__main__':
root = Tk()
app = App(root)
root.mainloop()
You definitely want the grid manager -- Pack only works for a vertical or horizontal stackup by itself. You can use multiple frames to work around it, but I find it's easier to expand a GUI if you just do it with Grid to start.
Here's what I've worked up real quick based what you said and the code. I reduced/removed the padding -- it looked huge for me -- and I set up two scrollbars, in a subframe to make the padding work out more easily. Note that to make the horizontal scrollbar useful your Text area needs to have wrap=NONE; otherwise you might as well use the easy 'ScrolledText' widget from tkinter.scrolledtext and skip the horizontal scroll bar.
I've now reframed things a bit to allow for resize, with a minimum size that shows the top buttons -- see the uses of minsize and row/columnconfigure.
BTW, it looks like your variables aren't being pulled from anywhere -- is that intentional?
from tkinter import *
class App:
def __init__(self, parent):
self.__setup_gui(parent) # Call Helper
parent.title('To be changed')
def __setup_gui(self, parent):
# First Row
self.rowframe = Frame(parent)
self.rowframe.grid()
self.cs_label = Label(self.rowframe, text='Change Set: ')
self.cs_label.grid(row=0, column=0, padx=2, pady=2)
self.cs_val = Entry(self.rowframe, width=10)
self.cs_val.grid(row=0, column=1, padx=2, pady=2)
self.get_button = Button(self.rowframe, text='Get', command=self.get_content)
self.get_button.grid(row=0, column=2, padx=2, pady=2)
parent.update_idletasks()
parent.minsize(width=self.rowframe.winfo_width(), height=self.rowframe.winfo_height())
# Text area and scrollbars
self.textframe = Frame(parent)
self.textframe.grid(row=1, columnspan=2, padx=2, pady=2, sticky=N+S+E+W)
self.hscroll = Scrollbar(self.textframe, orient=HORIZONTAL)
self.vscroll = Scrollbar(self.textframe)
self.text_area = Text(self.textframe, height=10, width=50, wrap=NONE, background='white', yscrollcommand=self.vscroll.set, xscrollcommand=self.hscroll.set)
self.text_area.grid(row=0, column=0, sticky=N+S+E+W)
self.hscroll.config(command=self.text_area.xview)
self.hscroll.grid(row=1, column=0, sticky=E+W)
self.vscroll.config(command=self.text_area.yview)
self.vscroll.grid(row=0, column=1, sticky=N+S)
# Row 0 defaults to 0
parent.rowconfigure(1, weight=1)
parent.columnconfigure(1, weight=1)
# Textarea setup
self.textframe.rowconfigure(0, weight=1)
self.textframe.columnconfigure(0, weight=1)
self.clipboard_var = IntVar()
self.notepad_var = IntVar()
def get_content(self):
print(self.clipboard_var.get())
print(self.notepad_var.get())
###################################################################################################
if __name__ == '__main__':
root = Tk()
app = App(root)
root.mainloop()
Now, all that said...you might get more visual appeal with PyGTK, PyQt, or wxPython, though tkinter coming "standard" is a nice feature.

Resources