pyQt写的一个读取图像的程序，

# PyQtImageViewer Yet another [PyQt](https://www.riverbankcomputing.com/software/pyqt/intro) (version 4 or 5) image viewer widget. Comes prepackaged with several configurable options for display (aspect ratio, scroll bars) and mouse interaction (zoom, pan, click signals). Displays a *QImage* or *QPixmap*. To display any other image format, you must first convert it to a *QImage* or *QPixmap*. Some useful image format conversion utilities: * [qimage2ndarray](https://github.com/hmeine/qimage2ndarray): [NumPy](http://www.numpy.org) *ndarray* <==> *QImage* * [ImageQt](https://github.com/python-pillow/Pillow/blob/master/PIL/ImageQt.py): [PIL](https://github.com/python-pillow/Pillow) *Image* <==> *QImage* **Author**: Marcel Goldschen-Ohm **Email**: <marcel.goldschen@gmail.com> **License**: MIT Copyright (c) 2015 Marcel Goldschen-Ohm ## INSTALL Everything's in `QtImageViewer.py`. Just put it somewhere where your project can find it. ### Requires: * [PyQt](https://www.riverbankcomputing.com/software/pyqt/intro) (version 4 or 5) ## A Simple Example ```python import sys try: from PyQt5.QtCore import Qt, QT_VERSION_STR from PyQt5.QtGui import QImage from PyQt5.QtWidgets import QApplication, QFileDialog except ImportError: try: from PyQt4.QtCore import Qt, QT_VERSION_STR from PyQt4.QtGui import QImage, QApplication, QFileDialog except ImportError: raise ImportError("Requires PyQt5 or PyQt4.") from QtImageViewer import QtImageViewer # Custom slot for handling mouse clicks in our viewer. # Just prints the (row, column) matrix index of the # image pixel that was clicked on. def handleLeftClick(x, y): row = int(y) column = int(x) print("Pixel (row="+str(row)+", column="+str(column)+")") if __name__ == '__main__': # Create the QApplication. app = QApplication(sys.argv) # Create an image viewer widget. viewer = QtImageViewer() # Set viewer's aspect ratio mode. # !!! ONLY applies to full image view. # !!! Aspect ratio always ignored when zoomed. # Qt.IgnoreAspectRatio: Fit to viewport. # Qt.KeepAspectRatio: Fit in viewport using aspect ratio. # Qt.KeepAspectRatioByExpanding: Fill viewport using aspect ratio. viewer.aspectRatioMode = Qt.KeepAspectRatio # Set the viewer's scroll bar behaviour. # Qt.ScrollBarAlwaysOff: Never show scroll bar. # Qt.ScrollBarAlwaysOn: Always show scroll bar. # Qt.ScrollBarAsNeeded: Show scroll bar only when zoomed. viewer.setHorizontalScrollBarPolicy(Qt.ScrollBarAsNeeded) viewer.setVerticalScrollBarPolicy(Qt.ScrollBarAsNeeded) # Allow zooming with right mouse button. # Drag for zoom box, doubleclick to view full image. viewer.canZoom = True # Allow panning with left mouse button. viewer.canPan = True # Load an image to be displayed. if QT_VERSION_STR[0] == '4': fileName = QFileDialog.getOpenFileName(None, "Open image file...") elif QT_VERSION_STR[0] == '5': fileName, dummy = QFileDialog.getOpenFileName(None, "Open image file...") image = QImage(fileName) # Display the image in the viewer. viewer.setImage(image) # Handle left mouse clicks with your own custom slot # handleLeftClick(x, y). (x, y) are image coordinates. # For (row, col) matrix indexing, row=y and col=x. # ImageViewerQt also provides similar signals for # left/right mouse button press, release and doubleclick. viewer.leftMouseButtonPressed.connect(handleLeftClick) # Show the viewer and run the application. viewer.show() sys.exit(app.exec_()) ```