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Matplotlib,使用imshow更快地刷新图像

imshow python-3.6 pyqt5 matplotlib python

Mathieu Gauquelin · 技术社区 · 7 年前

我正在做一个项目,我必须在图形用户界面的窗口上绘制一个320*250像素的图像,如果可能的话,每秒绘制60次。所以我试着用和 PyQt5 (因为我开始了解这些工具,并用它进行另一个项目的工作),方法如下:

import sys, random, matplotlib
from PyQt5 import QtCore, QtGui, QtWidgets

matplotlib.use('Qt5Agg')
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
import matplotlib.pyplot as plt

class SecondWindow(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(SecondWindow, self).__init__(parent)
        self.setupUi(self)

    def setupUi(self, Form):
        Form.setObjectName("Form")
        Form.resize(800, 600)

        self.figure = plt.figure()
        self.canvas = FigureCanvas(self.figure)
        self.axes = self.figure.add_subplot(111)

        self.setLayout(QtWidgets.QVBoxLayout())
        self.layout().addWidget(self.canvas)

        self.initialisationFigure()

        self.timer = QtCore.QTimer(self)
        self.timer.timeout.connect(self.majFigure)
        self.timer.start(16)

        self.timer2 = QtCore.QTimer(self)
        self.timer2.timeout.connect(self.NumberRefreshPerSecond)
        self.timer2.start(1000)

    def NumberRefreshPerSecond(self):
        print(self.count)
        self.count = 0

    def majFigure(self):
        self.count = self.count + 1
        self.plot.set_data([[random.random() for x in range(1, 320)] for y in range(1, 250)])
        # self.canvas.draw()
        self.axes.draw_artist(self.axes.patch)
        self.axes.draw_artist(self.plot)
        self.canvas.update()
        self.canvas.flush_events()

    def initialisationFigure(self):
        self.plot = self.axes.imshow([[random.random() for x in range(1,320)] for y in range(1,250)], interpolation='none')
        self.count = 0
        self.canvas.draw()

    def closeEvent(self, event):
        self.timer.stop()

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    form = SecondWindow()
    form.show()
    sys.exit(app.exec_())

我希望有人能帮我改进代码。

1 回复 | 直到 7 年前

9dogs 7 年前

Matplotlib生成出版物质量的绘图,但不幸的是,它不太适合实时绘图和视频。

pyqtgraph module . 它与pyqt5配合良好,旨在弥补 matplotlib

如果您正在做任何需要快速打印更新、视频或实时交互的事情,matplotlib不是最佳选择。
(from pyqtgraph site)

它还具有其他(可选)功能,如感兴趣区域、归一化和直方图绘制。

import sys, random, matplotlib
from PyQt5 import QtCore, QtGui, QtWidgets

import pyqtgraph as pg
import numpy as np


class SecondWindow(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(SecondWindow, self).__init__(parent)
        self.setupUi(self)

    def setupUi(self, Form):
        Form.setObjectName("Form")
        Form.resize(800, 600)

        self.im_widget = pg.ImageView(self)
        # uncomment to hide histogram
        # self.im_widget.ui.histogram.hide()

        self.setLayout(QtWidgets.QVBoxLayout())
        self.layout().addWidget(self.im_widget)

        self.initialisationFigure()

        self.timer = QtCore.QTimer(self)
        self.timer.timeout.connect(self.majFigure)
        self.timer.start(16)

        self.timer2 = QtCore.QTimer(self)
        self.timer2.timeout.connect(self.NumberRefreshPerSecond)
        self.timer2.start(1000)

    def NumberRefreshPerSecond(self):
        print(self.count)
        self.count = 0

    def majFigure(self):
        self.count = self.count + 1
        # numpy random.rand also much faster than list comprehension
        data = np.random.rand(320, 250)
        self.im_widget.setImage(data)

    def initialisationFigure(self):
        self.count = 0
        self.im_widget.show()

    def closeEvent(self, event):
        self.timer.stop()

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    form = SecondWindow()
    form.show()
    sys.exit(app.exec_())