Bdtjtk

I am doing a spectrum analyzer in python. Now I have a problem with adding markers to the spectrum graph. I do not know how to do this and could not find an example. Tell me please. Thank you in advance
Here is a part of my code where I create graphs and display them. Each graph is a separate stream.

enter image description here

class Test(QtGui.QDockWidget):



def __init__(self, nember, band, number_thread, bandw):

    super(Test, self).__init__()

    self.setAcceptDrops(True)



    self.bandw = bandw

    self.dockedWidget = QtGui.QWidget()

    self.setAcceptDrops(True)

    self.number_thread = number_thread

    self.image_item = pg.ImageItem()

    pos = np.array([0., 1., 0.5, 0.25, 0.75])

    color = np.array([[0, 0, 0, 0], [255, 255, 0, 255], [0, 0, 0, 255], (0, 0, 255, 255), (255, 0, 0, 255)],

                     dtype=np.ubyte)

    cmap = pg.ColorMap(pos, color)

    lut = cmap.getLookupTable(0.0, 1.0, 256)

    self.image_item.setLookupTable(lut)

    self.image_item.setLevels([-5, 16])





    self.win = pg.PlotWidget()

    self.win1 = pg.PlotWidget()

    self.hLine=pg.InfiniteLine(pos=0, angle=0, movable=True, pen='r')

    self.win.addItem(self.hLine)

    self.hLine.addMarker(',')

    self.win1.addItem(self.image_item)

    self.win.setLabel('left', 'Амплитуда'.decode('utf-8'), units='dB')

    self.win.setLabel('bottom', 'Частота'.decode('utf-8'), units='Hz')

    self.plot_data = self.win.plot()



    self.plot_maxhold = self.win.plot()

    self.win.setLimits(xMin=min(band), xMax=max(band))

    self.checkbut_maxhold = QtGui.QCheckBox('МАКСХОЛД'.decode('utf-8'))

    self.checkbutton = QtGui.QCheckBox('ВАША РЕКЛАМА1'.decode('utf-8'))

    self.checkbutt2 = QtGui.QCheckBox('ВАША РЕКЛАМА2'.decode('utf-8'))

    self.nember = nember

    button_layout = QtGui.QHBoxLayout()

    button_layout.addWidget(self.checkbut_maxhold)

    button_layout.addWidget(self.checkbutton)

    button_layout.addWidget(self.checkbutt2)



    layout = QtGui.QVBoxLayout()

    layout.addItem(button_layout)

    layout.addWidget(self.win)

    layout.addWidget(self.win1)

    #layout.addLayout(self.image_widget)

    # self.dockedWidget.addWidget(self.win)



    self.dockedWidget.setLayout(layout)

    self.setWidget(self.dockedWidget)

    self.thread = Tread_400(self.plot_data,self.image_item, self.plot_maxhold, self.nember, band)

    self.thread.start()

    self.checkbut_maxhold.stateChanged.connect(self.state_changed_button1)



def closeEvent(self, QCloseEvent):

    data.list_band.remove(data.list_band[data.list_freq.index(self.bandw)])

    data.list_freq.remove(self.bandw)



    print (self.nember)

    self.thread.stop()



    del data.shared_data[self.nember]

    print(data.list_band)

    print(data.list_freq)



def set_value(self):

    print(1)

    self.range_changed.emit(22)



def tested(self, vall):

    print (vall)



def state_changed_button1(self, int):

    if self.checkbut_maxhold.isChecked():

        self.thread.flag_maxhold = True

        print("CHECKED!")



    else:

        print("UNCHECKED!")



        self.thread.flag_maxhold = False



def state_changed_button2(self, int):

    if self.checkbut_maxhold.isChecked():

        self.thread.reklama1 = True

        print("CHECKED!")



    else:

        print("UNCHECKED!")



        self.thread.reklama1 = False



def state_changed_button3(self, int):

    if self.checkbut_maxhold.isChecked():

        self.thread.reklama2 = True

        print("CHECKED!")



    else:

        print("UNCHECKED!")



        self.thread.reklama2 = False



class Tread_400(QtCore.QThread):

    def __init__(self, wind,plot_waterfall, plot_maxhold, number, band):

        QtCore.QThread.__init__(self)

        print(self.currentThreadId())

        self.flag_maxhold = None

        self.reklama1 = True

        self.reklama2 = False

        self.x_axis = band

        self.img_array = np.zeros((100, len(self.x_axis)))

        self.plot_maxhold = plot_maxhold

        self.wind = wind

        self.plot_waterfall=plot_waterfall

        self.number = number

        self.timer1 = QtCore.QTimer()

        print(self.timer1.timerId())

        self.maxhold22 = np.ones(data.shared_data[self.number].size) * -1000

        print(self.number)

        self.timer1.timeout.connect(self.plot_data)



    def run(self):



        self.timer1.start(0.0001)



    def plot_data(self):



        self.wind.setData(self.x_axis, data.shared_data[self.number], clear=True)

        if self.flag_maxhold:

            maxhhoold = self.maxhold(data.shared_data[self.number], self.maxhold22)

            self.plot_maxhold.setData(self.x_axis, maxhhoold[:], clear=True, pen='r')

        elif self.flag_maxhold == False:

            self.plot_maxhold.clear()

            self.maxhold22 = np.ones(data.shared_data[self.number].size) * -1000

            self.maxhold22=None

        if self.reklama1==True:

            start=time.time()

            self.img_array = np.roll(self.img_array, -1, 0)

            self.img_array[-1:] = data.shared_data[self.number]

            self.plot_waterfall.setImage(self.img_array.T, autoLevels=False)

            print (time.time()-start)

    def stop(self):

        self.timer1.stop()

        self.terminate()

        self.wait()





    def maxhold(self, data, maxhold):

        for i in np.arange(data.size):

            if data[i] > maxhold[i]:

                maxhold[i] = data[i]

        return maxhold

It seems that you can use a TextItem with or without an ArrowItem (or CurveArrow) would get you close to what you want?

See the example file for TextItem: pyqtgraph/examples/text.py