Currently making an application which allows me to make a lightshow with some custom build LED-Controllers and for that i need to draw the waveform of the song on a widget.
Although I managed to do this it is still VERY slow (especially with .wav files longer than a few seconds). The thing is I don't know how to optimise this or if my approach is correct since i cant find anything on the web.
So my question is: what is the right way to go about this? How do audio editors display the waveform and are able to zoom in and out without lag?
So my current attempt at this is by using QGraphicsView and a QGraphicsScene, the latter one supposedly being made to represent a lot of custom graphics items.
The main function to look at here is drawWav() in class WavDisplay
Showcreator.py:
from PyQt6 import uic
from PyQt6.QtCore import (
QSize,
Qt
)
from PyQt6.QtGui import (
QAction,
QPen,
QPixmap,
QPainter,
QColor,
QImage
)
from PyQt6.QtWidgets import (
QMainWindow,
QWidget,
QStatusBar,
QFileDialog,
QGraphicsScene,
QGraphicsView,
QGridLayout
)
import sys
import wave
import pyaudio
import numpy as np
import threading
import soundfile as sf
import threading
class MainWindow(QMainWindow):
# audio chunk rate
CHUNK = 1024
def __init__(self):
super().__init__()
# set window title
self.setWindowTitle("LED Music Show")
# create file button
button_action = QAction("Open .wav file", self)
button_action.setStatusTip("Open a Wave file to the Editor.")
button_action.triggered.connect(self.openWav)
# set status bar
self.setStatusBar(QStatusBar(self))
# create menubar
menu = self.menuBar()
# add file button to status bar
file_menu = menu.addMenu("&File")
file_menu.addAction(button_action)
# create layout
layout = QGridLayout()
layout.setContentsMargins(0,0,0,0)
# create Wave display object
self.waveformspace = WavDisplay()
# add widget to layout
layout.addWidget(self.waveformspace, 0, 1)
self.centralWidget = QWidget()
self.centralWidget.setLayout(layout)
self.setCentralWidget(self.centralWidget)
def openWav(self):
# file selection window
self.filename, check = QFileDialog.getOpenFileName(self,"QFileDialog.getOpenFileName()", "","Wave files (*.wav)")
self.file = None
# try to open .wav with two methods
try:
try:
self.file = wave.open(self.filename, "rb")
except:
print("Failed to open with wave")
try:
self.file, samplerate = sf.read(self.filename, dtype='float32')
except:
print("Failed to open with soundfile")
# read file and convert it to array
self.signal = self.file.readframes(-1)
self.signal = np.fromstring(self.signal, dtype = np.int16)
# set file for drawing
self.waveformspace.setWavefile(self.signal)
self.waveformspace.drawWav()
# return file cursor to start
self.file.rewind()
# start thread for the player
# self.player = threading.Thread(target = self.playWav)
# try:
# self.player.daemon = True
# except:
# print("Failed to set player to Daemon")
# self.player.start()
except:
print("Err opening File")
def playWav(self):
lastFile = None
lastpos = None
p = pyaudio.PyAudio()
data = None
sampwidth = None
fps = None
chn = None
farmes = None
currentpos = 0
framespersec = None
while True:
if self.file != lastFile:
# get file info
sampwidth = self.file.getsampwidth()
fps = self.file.getframerate()
chn = self.file.getnchannels()
frames = self.file.getnframes()
lastFile = self.file
# open audio stream
stream = p.open(format = p.get_format_from_width(sampwidth), channels = chn, rate = fps, output = True)
# read first frame
data = self.file.readframes(self.CHUNK)
framespersec = sampwidth * chn * fps
print("file changed")
if self.pos != lastpos:
# read file for offset
self.file.readframes(int(self.pos * framespersec))
lastpos = self.pos
frames = self.file.getnframes()
print("pos changed")
while data and self.running:
# writing to the stream
stream.write(data)
data = self.file.readframes(self.CHUNK)
currentpos = currentpos + self.CHUNK
# cleanup stuff.
self.file.close()
stream.close()
p.terminate()
return
class WavDisplay(QGraphicsView):
file = None
maxAmplitude = 0
fileset = False
def __init__(self):
super().__init__()
def setWavefile(self, externFile):
self.file = externFile
self.fileset = True
# find the max deviation from 0 db to set draw borders
if max(self.file) > abs(min(self.file)):
self.maxAmplitude = max(self.file) * 2
else:
self.maxAmplitude = abs(min(self.file)) * 2
def drawWav(self):
# only draw when there is a set file
if self.fileset:
width = self.frameGeometry().width()
height = self.frameGeometry().height()
vStep = height / self.maxAmplitude
scene = QGraphicsScene(self)
# to draw on the middle of the widget
h = height / 2
# method 1 of drawing: looks at sections of the file and determines the max and min amplitude that would be visible on a single "column" of pixels and draws a vertical line between them
if width < len(self.file):
hStep = len(self.file) / width
drawArray = np.empty((width, 3))
for i in range(width - 1):
buffer = self.file[int(np.ceil(i * hStep)) : int(np.ceil((i + 1) * hStep))]
drawArray[i][0] = (min(buffer) * vStep) + h
drawArray[i][1] = (max(buffer) * vStep) + h
for i in range(width - 1):
self.line = scene.addLine(i, drawArray[i][0], i, drawArray[i][1])
# method 2 of drawing: this only happens when the amount of samples to draw is less than the windows width (e.g. when zoomed in and you can see the individual samples)
else:
hStep = width / len(self.file)
for i in range(len(self.file) - 1):
self.line = scene.addLine(i * hStep, int(self.file[i] * vStep + h), (i + 1) * hStep, int(self.file[i + 1] * vStep + h))
self.setScene(scene)
self.setContentsMargins(0,0,0,0)
self.show()
def resizeEvent(self, event) -> None:
# has to redraw the wave file if the window gets resized
self.drawWav()
# class not used yet
class effectList(QGraphicsView):
bpm = 130
trackBeats = 0
def __init__(self):
super().__init__()
def setBeatsAndBpm(self, trackLenght, Bpm):
self.bpm = Bpm
self.trackBeats = (trackLenght / 60) * self.bpm
main.py:
from PyQt6 import QtCore, QtGui, QtWidgets
from Showcreator import MainWindow
app = QtWidgets.QApplication([])
window = MainWindow()
window.show()
app.exec()
In essence: Where do i need to start to make this wave file view like one in for example Audacity? (Aka a fast rendering view which doesnt take ages)
Btw i have looked at seemingly duplicates of this question and as you can see in the code i have an algorythem that is only drawing as many lines as the window is wide and not all the 100000+ lines for each sample so the main problem i have should be the rendering method i guess.
Edit: I have all the data preloaded as im loading a wave file and convert it into a numpy array. And i need to display the file as a whole but be able to zoom in dynamically-
Ok, so I've been tasked with creating a VERY simple GUI at work (I'm an intern). The task is to eventually connect to a machine and process real data, but right now I'm working on randomly generated sine data with noise. I've chose to work in Python 3.0, and use wxpython to create my GUI components.
As I want everything to appear on the same window, I'm using panels (hence wx.lib.plot.PlotCanvas rather than something like matplotlib.pyplot)
The problem that I have is that over time, the plot seems to 'expand' off of the panel. This is temporarily solved when I manually resize the window, but resumes again immediately after (you need to run the code to see what I mean).
Expansion over time in panel
Another problem (that has bugged me since I have started writing the code) is that sometimes when I resize the window (manually) or minimize it and then maximize it again, the timer randomly starts and stops.
I have tried all sorts of things (changing padding in sizers, extra arguments, changing time between refreshes GetBestSize()) but I believe that I simply don't understand wxpython well enough to identify where the problem is
I would really appreciate any help you can shed on either of these problems (I don't know, they might even be linked to each other).
FYI: I am not an experienced coder, and my code is not finished (I have more functions to code, but I feel like I should resolve this first). I have constructed this code by looking at different techniques from various tutorials and websites like stackoverflow, so I know it's not formatted well and could definitely be made more efficient. Also, I have removed some parts just to be safe about confidentiality - nothing important, just strings in messages.
PS: If you do have an easier way to do the whole plot/update thing that doesn't have this problem (preferably still in wx) I would be thrilled to hear that as well
And here's my code:
EDIT: Solved the expanding problem by using self.p2.SetSize((W+0,L+0)) instead of (self.p2.GetBestSize())
EDIT: Made transitions much smoother by just regenerating data and redrawing it on existing canvas in the evt_timer function (instead of recreating the whole canvas, which gave a blink-y appearance if you know what I mean)
import wx
import numpy as np
import matplotlib.pyplot as plt
from scipy.optimize import leastsq
import wx.lib.plot as plot
import time
import os
wildcard = "Text File (*.txt)|*.txt|"\
"Picture (*.png)|*.png|"\
"All files (*.*)|*.*"#This wildcard shows the options for file endings in the "SAVE" tab - see OnSave(self,event)
wildcard2 = "Picture (*.png)|*.png|"\
"Text File (*.txt)|*.txt|"\
"All files (*.*)|*.*"
class PlotCanvas(plot.PlotCanvas):
def __init__(self,parent,id,size,accepted):
"""
This randomly generates sine data (with noise) and plots it to a panel.
Incorporated as a separate class instead of instatiating it as a plot.PlotCanvas object
to overcome an issue of the size of the plot in the panel.
"""
plot.PlotCanvas.__init__(self,parent,id,style=wx.BORDER_SUNKEN,size = size)
N = 100 # number of data points
self.t = np.linspace(0, 4*np.pi, N)
f = 1.15247 # Optional!! Advised not to use
self.data = 3.0*np.sin(f*self.t+0.001) + 0.5 + np.random.randn(N) # create artificial data with noise
guess_mean = np.mean(self.data)
guess_phase = 0
guess_freq = 1
guess_amp = 1
optimize_func = lambda x: x[0]*np.sin(x[1]*self.t+x[2]) + x[3] - self.data
est_amp, est_freq, est_phase, est_mean = leastsq(optimize_func, [guess_amp, guess_freq, guess_phase, guess_mean])[0]
fine_t = np.arange(0,max(self.t),0.1)
data_fit=est_amp*np.sin(est_freq*fine_t+est_phase)+est_mean
multiplier = 1
dataset1 = [(x,[d for d in self.data][[td for td in self.t].index(x)])for x in [td for td in self.t]]
fitdata1 = [(x,[df for df in data_fit][[tf for tf in fine_t].index(x)]) for x in [tf for tf in fine_t]]
dataset =[(x,y*multiplier) for (x,y) in dataset1]
fitdata = [(x,y*multiplier) for (x,y) in fitdata1]
self.data = dataset
self.data2 = fitdata
line = plot.PolyLine(self.data,legend = 'random',colour = 'light blue', width =2)
line2 = plot.PolyLine(self.data2,legend = 'sineline',colour ='black',width =2)
a = []
if "D" in accepted:
a.append(line)
if "S" in accepted:
a.append(line2)
if "G" in accepted:
pass
if "L" in accepted:
pass
gc = plot.PlotGraphics(a,'Line Graph','X','Y')
xmin = self.t[0]-0.01*(self.t[-1]-self.t[0])
xmax = self.t[-1]+0.01*(self.t[-1]-self.t[0])
self.Draw(gc,xAxis=(xmin,xmax),yAxis=(min([x[1] for x in dataset])-0.01*(max([x[1] for x in dataset])-min([x[1] for x in dataset])),
max([x[1] for x in dataset])+0.01*(max([x[1] for x in dataset])-min([x[1] for x in dataset]))))
#self.showLegend = True
#self.enableZoom = True
def Dialog(self, parent, message, c):# Will be used to notify the user of errors/processes
if c == "W":
caption = "Warning!"
dlg = wx.MessageDialog(parent, message, caption, wx.OK | wx.ICON_WARNING)
elif c == "I":
caption = "Information"
dlg = wx.MessageDialog(parent, message, caption, wx.OK | wx.ICON_INFORMATION)
dlg.ShowModal()
dlg.Destroy()#Destroys dialog on close
class Frame(wx.Frame):
"""
This is the main class. In it, we declare the separate panels, canvas, menubar, buttons and sizers.
"""
def __init__(self,parent,id,title):
wx.Frame.__init__(self, parent, id, title, wx.DefaultPosition)
self.CurrentDirectory = os.getcwd()
self.timer=wx.Timer(self)#Instantiating the timer
self.count=0
self.Bind(wx.EVT_TIMER,self.evt_timer)#Binding it to itself so that it is always triggered
self.Bind(wx.EVT_PAINT,self.paint)
menubar = wx.MenuBar()
fileMenu = wx.Menu() #Creating the Menubar at the top
#Creating 3 menus: fileMenu,fit,and help
save = wx.Menu()
z = wx.MenuItem(save,wx.ID_ANY,'Save Raw Data\tCtrl+D')
self.Bind(wx.EVT_MENU,self.OnSave,z)
save.Append(z)
z= wx.MenuItem(save,wx.ID_ANY,'Save Image\tCtrl+I')
self.Bind(wx.EVT_MENU,self.OnSaveImage,z)
save.Append(z)
fileMenu.AppendSubMenu(save,'&Save')
fileMenu.AppendSeparator()
z = wx.MenuItem(fileMenu, wx.ID_EXIT, '&Quit\tCtrl+W')
self.Bind(wx.EVT_MENU, self.OnQuit, z)
fileMenu.Append(z)
fit = wx.Menu()#Making a check menu
self.gaussian = fit.Append(wx.ID_ANY,'Gaussian',kind = wx.ITEM_CHECK)
#self.Bind(wx.EVT_MENU,self.ToggleGaussian,self.gaussian)
fit.Check(self.gaussian.GetId(),False)
self.sine = fit.Append(wx.ID_ANY,'Sine',kind = wx.ITEM_CHECK)
#self.Bind(wx.EVT_MENU,self.ToggleSine,self.sine)
fit.Check(self.sine.GetId(),False)
self.linear = fit.Append(wx.ID_ANY,'Linear',kind=wx.ITEM_CHECK)
#self.Bind(wx.EVT_MENU,self.ToggleLinear,self.linear)
fit.Check(self.linear.GetId(),False)
help = wx.Menu()
z = wx.MenuItem(help,wx.ID_ANY,'&About\tCtrl+H')
self.Bind(wx.EVT_MENU,self.OnHelp,z)
help.Append(z)
menubar.Append(fileMenu, '&File')
menubar.Append(fit, '&Fit')
menubar.Append(help, '&Help')#adding menus to menubar
self.SetMenuBar(menubar)#formatting the frame with menubar
self.sp = wx.SplitterWindow(self)#Splitting the window into 2 panels
self.p1 = wx.Panel(self.sp,style = wx.SUNKEN_BORDER)#For buttons and user events
self.p2 = wx.Panel(self.sp,style = wx.SUNKEN_BORDER)#For display of the plot
self.sp.SplitVertically(self.p1,self.p2,300)
sizer = wx.GridBagSizer(3, 3)#Versatile sizer for layout of first panel self.p1
bitmappath = self.CurrentDirectory + "\\BITMAPS"
bmp = wx.Bitmap(bitmappath+"\\SAVE.BMP",wx.BITMAP_TYPE_BMP)
self.saveBtn = wx.BitmapButton(self.p1,wx.ID_ANY,bitmap = bmp,size =(bmp.GetWidth()+10,bmp.GetHeight()+10))
self.Bind(wx.EVT_BUTTON,self.OnSave,self.saveBtn)
sizer.Add(self.saveBtn, (0, 0), wx.DefaultSpan, wx.ALL,5)
bmp = wx.Bitmap(bitmappath +"\\START.BMP",wx.BITMAP_TYPE_BMP)
self.startBtn = wx.BitmapButton(self.p1,-1,bitmap = bmp,size =(bmp.GetWidth()+10,bmp.GetHeight()+10))# A button that starts and stops the plotting
self.startBtn.startval = "START"
self.Bind(wx.EVT_BUTTON,self.paint,self.startBtn)
sizer.Add(self.startBtn, (0, 1), wx.DefaultSpan,wx.ALL,5)
sizer1 = wx.BoxSizer(wx.VERTICAL)
W,L = self.p2.GetSize()
self.p2.canvas = PlotCanvas(self.p2,wx.ID_ANY,(W,L),["D"])
sizer1.Add(self.p2.canvas,1,wx.ALL,0,0)
self.p2.SetSizerAndFit(sizer1)
self.p1.SetSizerAndFit(sizer)
self.p2.SetSizerAndFit(sizer1)
self.p2.SetSize(W,L)
self.Maximize(True)
self.Centre()
self.Show()
############### event methods ###########
def paint(self,event):
"""
Updates the canvas based on the value of the startbtn(not the image). Bound to self.timer.
"""
bitmappath = self.CurrentDirectory + "\\BITMAPS"
if self.startBtn.startval == "START":
self.timer.Start(1)# increase the value for more time
bmp = wx.Bitmap(bitmappath + "\\STOP.BMP",wx.BITMAP_TYPE_BMP)
self.startBtn.SetBitmap(bmp)
self.startBtn.startval = "STOP"
elif self.startBtn.startval == "STOP":
self.timer.Stop()
bmp = wx.Bitmap(bitmappath+ "\\START.BMP",wx.BITMAP_TYPE_BMP)
self.startBtn.SetBitmap(bmp)
self.startBtn.startval = "START"
def evt_timer(self,event):
self.count +=1
if self.count== 10:# By increasing count (or the number in self.timer.Start()) you can increase the interval between updates
#self.p2.canvas.Clear()
sizer1 = wx.BoxSizer(wx.VERTICAL)
W,L = self.p2.GetSize()
a = ["D"]
if self.sine.IsChecked():
a.append("S")
elif self.linear.IsChecked():
a.append("L")
elif self.gaussian.IsChecked():
a.append("G")
self.p2.canvas = PlotCanvas(self.p2,wx.ID_ANY,(W,L),a)
sizer1.Add(self.p2.canvas,1,wx.ALL,0,0)
self.p2.SetSizerAndFit(sizer1)
self.p2.SetSize(self.p2.GetBestSize())
self.count=0 # reset the count
def Dialog(self, parent, message, c):# Will be used to notify the user of errors/processes
if c == "W":
caption = "Warning!"
dlg = wx.MessageDialog(parent, message, caption, wx.OK | wx.ICON_WARNING)
elif c == "I":
caption = "Information"
dlg = wx.MessageDialog(parent, message, caption, wx.OK | wx.ICON_INFORMATION)
dlg.ShowModal()
dlg.Destroy()#Destroys dialog on close
def OnSave(self,event):#Triggered by menubar and button
try:
rawdata = self.p2.canvas.data
raw_X =[x[0] for x in rawdata]
raw_Y =[x[1] for x in rawdata]
dlg = wx.FileDialog(#Code for this from http://www.blog.pythonlibrary.org
self, message="Save file as ...",
defaultDir=self.CurrentDirectory,
defaultFile=str(time.ctime()), wildcard=wildcard, style=wx.FD_SAVE
)
if dlg.ShowModal() == wx.ID_OK:
path = dlg.GetPath()
dlg.Destroy()
f = open(path+".txt","w+")
for i in range(len(raw_X)):
f.write(str(raw_X[i])+"\t"+str(raw_Y[i])+"\n")
f.close()
self.Dialog(None,"File successfully saved","I")
except UnboundLocalError:#Catch error when user closes save window without selecting any directory or filename
pass
def OnSaveImage(self,event):
try:
rawdata = self.p2.canvas.data
raw_X = [x[0] for x in rawdata]
raw_Y = [x[1] for x in rawdata]
dlg = wx.FileDialog(
self, message="Save file as ...",
defaultDir=self.CurrentDirectory,
defaultFile=str(time.ctime()), wildcard=wildcard2, style=wx.FD_SAVE
)
if dlg.ShowModal() == wx.ID_OK:
path = dlg.GetPath()
dlg.Destroy()
fig1 = plt.figure()
plt.plot(raw_X,raw_Y)
plt.title("Raw Data")
fig1.savefig(path+".png")
self.Dialog(None,"File successfully saved","I")
except UnboundLocalError:
pass
def OnMultiply(self,e):
try:
factor = self.x.GetValue()
factor = float(factor)
self.IntegrationTime = factor
except ValueError as e:
self.Dialog(None,str(e),"W")
def OnQuit(self, e):
self.Close()
def OnHelp(self,e):
self.Dialog(None,"N/A","I")
def ToggleSine(self,e):
pass
def ToggleLinear(self,e):
self.Dialog(None,"Not added yet","W")
def ToggleGaussian(self,e):
self.Dialog(None,"Not added yet","W")
if __name__ =="__main__":
app=wx.App()
Frame(None,-1,"N/A")
app.MainLoop()
I am building an application to continuously display an image fetched from an IP camera. I have figured out how to fetch the image, and how to also display the image using Tkinter. But I cannot get it to continuously refresh the image. Using Python 2.7+.
Here is the code I have so far.
import urllib2, base64
from PIL import Image,ImageTk
import StringIO
import Tkinter
URL = 'http://myurl.cgi'
USERNAME = 'myusername'
PASSWORD = 'mypassword'
def fetch_image(url,username,password):
# this code works fine
request = urllib2.Request(url)
base64string = base64.encodestring('%s:%s' % (username, password)).replace('\n', '')
request.add_header("Authorization", "Basic %s" % base64string)
result = urllib2.urlopen(request)
imgresp = result.read()
img = Image.open(StringIO.StringIO(imgresp))
return img
root = Tkinter.Tk()
img = fetch_image(URL,USERNAME,PASSWORD)
tkimg = ImageTk.PhotoImage(img)
Tkinter.Label(root,image=tkimg).pack()
root.mainloop()
How should I edit the code so that the fetch_image is called repeatedly and its output updated in the Tkinter window?
Note that I am not using any button-events to trigger the image refresh, rather it should be refreshed automatically, say, every 1 second.
Here is a solution that uses Tkinter's Tk.after function, which schedules future calls to functions. If you replace everything after your fetch_image definition with the snipped below, you'll get the behavior you described:
root = Tkinter.Tk()
label = Tkinter.Label(root)
label.pack()
img = None
tkimg = [None] # This, or something like it, is necessary because if you do not keep a reference to PhotoImage instances, they get garbage collected.
delay = 500 # in milliseconds
def loopCapture():
print "capturing"
# img = fetch_image(URL,USERNAME,PASSWORD)
img = Image.new('1', (100, 100), 0)
tkimg[0] = ImageTk.PhotoImage(img)
label.config(image=tkimg[0])
root.update_idletasks()
root.after(delay, loopCapture)
loopCapture()
root.mainloop()
I'm building a small GUI application, that once a button is clicked a new top level window will open and it should display images for buttons.
I can get the image button to work on the root window, but not on the top level window. Only a blackbox appears.
I have a generic button on both windows and they do work.
I'm new to Python.
import Tkinter
from Tkinter import *
from PIL import ImageTk, Image
root = Tkinter.Tk()
root.title("First Window")
root.configure(background = "black")
def new_window():
win2 = Toplevel(root)
win2.geometry("650x350+50+40")
win2.title("Second Window!")
win2.configure(background = "white")
def close1():
win2.destroy()
img1 = ImageTk.PhotoImage(Image.open("./images/close.gif"))
c1 = Button(win2, image = img1, bg ="black", command = close1)
c1.grid(row = 1)
c2= Tkinter.Button(win2, text='close', command = close1)
c2.grid(row = 2)
nw = Tkinter.Button(root, text = 'New Window' , command = new_window)
nw.grid(row = 1)
def close3():
root.destroy()
img3 = ImageTk.PhotoImage(Image.open("./images/close.gif"))
c3 = Button(root, image = img3, bg ="black", command = close3)
c3.grid(row = 2)
root.mainloop()
When you create the new toplevel, you are using a local variable to refer to the image. Because of this, when the method exits, the garbage collector will delete the image. You need to save a reference in a global variable, or some other way to protect it from the garbage collector
A common way to save a reference is to make it an attribute of the button:
img1 = ImageTk.PhotoImage(...)
c1 = Button(...)
c1.image = img1