我如何使用PyQt5 / PySide或任何其他Python库以全屏模式在辅助监视器上显示所需的图像?过去,我使用帧缓冲图像查看器(Fbi和Fbi improved)。但是,这种方法要求我使用Linux。我更喜欢在Windows中工作,最好使用Python查找解决方案。
动机/环境
我正在研究基于DLP投影的3D打印过程。当我使用HDMI将DLP投影仪连接到Windows PC时,它会显示为第二台监视器。我只想将此辅助监视器(DLP)专用于显示3D打印过程所需的图案图像(png,bmp或svg)。我想使用Python以编程方式控制要显示的图像。这是https://3dprinting.stackexchange.com/questions/1217/how-to-display-images-on-dlp-using-hdmi-for-3d-printing的后续问题
部分解决方案和问题
下面的代码是一种可能的解决方案,但是我不确定它是正确还是最有效的方法。我发现使用PyQt5的两种方法:1)使用启动画面,以及2)使用QLabel。我的代码遇到以下问题:
对于3D打印应用,解决方案需要满足以下要求:
import time
start_time = time.time()
import sys
from PyQt5.QtWidgets import QApplication, QLabel, QSplashScreen
from PyQt5.QtGui import QPixmap, QCursor
from PyQt5.QtCore import Qt
import os
app = QApplication(sys.argv)
total_loops = 1
for i in range(total_loops):
# https://doc.qt.io/qtforpython/index.html
# https://www.riverbankcomputing.com/static/Docs/PyQt5/module_index.html
s = app.screens()[1] # Get the secondary screen
# Display info about secondary screen
print('Screen Name: {} Size: {}x{} Available geometry {}x{} '.format(s.name(), s.size().width(), s.size().height(), s.availableGeometry().width(), s.availableGeometry().height()))
# Hide cursor from appearing on screen
app.setOverrideCursor(QCursor(Qt.BlankCursor)) # https://forum.qt.io/topic/49877/hide-cursor
# Select desired image to be displayed
pixmap = QPixmap('test.png')
# Splash screen approach
# https://doc.qt.io/qtforpython/PySide2/QtWidgets/QSplashScreen.html?highlight=windowflags
splash = QSplashScreen(pixmap) # Set the splash screen to desired image
splash.show() # Show the splash screen
splash.windowHandle().setScreen(s) # Set splash screen to secondary monitor https://stackoverflow.com/a/30597458/4988010
splash.showFullScreen() # Show in splash screen in full screen mode
# # Qlabel apporach
# l = QLabel()
# l.setPixmap(pixmap)
# l.move(1920,0)
# l.show()
# l.windowHandle().setScreen(s) # https://stackoverflow.com/a/30597458/4988010
# l.showFullScreen()
time.sleep(0.5)
end_time = time.time()
print('Execution time: ', end_time-start_time )
sys.exit(app.exec_())
下面的代码是我的问题的一种可能的解决方案。我的解决方案假定Qt仅用于全屏显示图像,而不用于其余逻辑。因此,我不得不run the QT app in a secondary thread。这是因为当我运行函数app.exec_()
时,Qt将连续运行事件循环,从而阻塞了不依赖Qt的其余Python逻辑。据我了解,不建议在主线程外运行QApplication
,因此,我欢迎经验丰富的用户发布更好的方法。
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import QObject, pyqtSignal
import sys
import time
import threading
def main():
print('Step 1')
print(' Some logic here without QT')
print('Step 2')
print(' Launch QT app to run in background')
myapp = myImageDisplayApp()
print('Step 3')
print(' Continue some logic while QT running in background')
time.sleep(2)
print('Step 4')
print(' Update the displayed image in the QT app running in background')
myapp.emit_image_update('qt_test_static_1.png')
time.sleep(2)
print('Step 5')
print(' Update displayed image again')
myapp.emit_image_update('qt_test_static_2.png')
time.sleep(2)
class myImageDisplayApp (QObject):
# Define the custom signal
# https://www.riverbankcomputing.com/static/Docs/PyQt5/signals_slots.html#the-pyqtslot-decorator
signal_update_image = pyqtSignal(str)
def __init__ (self):
super().__init__()
# Setup the seperate thread
# https://stackoverflow.com/a/37694109/4988010
self.thread = threading.Thread(target=self.run_app_widget_in_background)
self.thread.daemon = True
self.thread.start()
def run_app_widget_in_background(self):
self.app = QApplication(sys.argv)
self.my_bg_qt_app = qtAppWidget(main_thread_object=self)
self.app.exec_()
def emit_image_update(self, pattern_file=None):
print('emit_image_update signal')
self.signal_update_image.emit(pattern_file)
class qtAppWidget (QLabel):
def __init__ (self, main_thread_object):
super().__init__()
# Connect the singal to slot
main_thread_object.signal_update_image.connect(self.updateImage)
self.setupGUI()
def setupGUI(self):
self.app = QApplication.instance()
# Get avaliable screens/monitors
# https://doc.qt.io/qt-5/qscreen.html
# Get info on selected screen
self.selected_screen = 0 # Select the desired monitor/screen
self.screens_available = self.app.screens()
self.screen = self.screens_available[self.selected_screen]
self.screen_width = self.screen.size().width()
self.screen_height = self.screen.size().height()
# Create a black image for init
self.pixmap = QPixmap(self.screen_width, self.screen_height)
self.pixmap.fill(QColor('black'))
# Create QLabel object
self.app_widget = QLabel()
# Varioius flags that can be applied to make displayed window frameless, fullscreen, etc...
# https://doc.qt.io/qt-5/qt.html#WindowType-enum
# https://doc.qt.io/qt-5/qt.html#WidgetAttribute-enum
self.app_widget.setWindowFlags(Qt.FramelessWindowHint | Qt.WindowDoesNotAcceptFocus | Qt.WindowStaysOnTopHint)
# Hide mouse cursor
self.app_widget.setCursor(Qt.BlankCursor)
self.app_widget.setGeometry(0, 0, self.screen_width, self.screen_height) # Set the size of Qlabel to size of the screen
self.app_widget.setWindowTitle('myImageDisplayApp')
self.app_widget.setAlignment(Qt.AlignLeft | Qt.AlignTop) #https://doc.qt.io/qt-5/qt.html#AlignmentFlag-enum
self.app_widget.setPixmap(self.pixmap)
self.app_widget.show()
# Set the screen on which widget is on
self.app_widget.windowHandle().setScreen(self.screen)
# Make full screen
self.app_widget.showFullScreen()
def updateImage(self, pattern_file=None):
print('Pattern file given: ', pattern_file)
self.app_widget.clear() # Clear all existing content of the QLabel
self.pixmap = QPixmap(pattern_file) # Update pixmap with desired image
self.app_widget.setPixmap(self.pixmap) # Show desired image on Qlabel
if __name__ == "__main__":
main()
我也要感谢@ekhumoro向我指出QWidget属性/标志。