How to import QtMultimedia module in ubuntu 16.04 in a python program

[sahil713]

I encountered this error while compiling one of the examples given in the qt websites.
I have updated pyqt4,tried installing all the qt libraries from synaptic package manager, installed gstreamer 1.0.

```

The code:
//

from math import pi, sin
import struct, sys

from PyQt4.QtCore import QBuffer, QByteArray, QIODevice, Qt
from PyQt4.QtGui import QApplication, QFormLayout, QLineEdit, QHBoxLayout,
QPushButton, QSlider, QVBoxLayout, QWidget
from PyQt4.QtMultimedia import QAudio, QAudioDeviceInfo, QAudioFormat, QAudioOutput

class Window(QWidget):

   def __init__(self, parent = None):

       QWidget.__init__(self, parent)

       format = QAudioFormat()
       format.setChannels(1)
       format.setFrequency(22050)
       format.setSampleSize(16)
       format.setCodec("audio/pcm")
       format.setByteOrder(QAudioFormat.LittleEndian)
       format.setSampleType(QAudioFormat.SignedInt)
       self.output = QAudioOutput(format, self)

       self.frequency = 440
       self.volume = 0
       self.buffer = QBuffer()
       self.data = QByteArray()

       self.deviceLineEdit = QLineEdit()
       self.deviceLineEdit.setReadOnly(True)
       self.deviceLineEdit.setText(QAudioDeviceInfo.defaultOutputDevice().deviceName())

       self.pitchSlider = QSlider(Qt.Horizontal)
       self.pitchSlider.setMaximum(100)
       self.volumeSlider = QSlider(Qt.Horizontal)
       self.volumeSlider.setMaximum(32767)
       self.volumeSlider.setPageStep(1024)

       self.playButton = QPushButton(self.tr("&Play"))

       self.pitchSlider.valueChanged.connect(self.changeFrequency)
       self.volumeSlider.valueChanged.connect(self.changeVolume)
       self.playButton.clicked.connect(self.play)

       formLayout = QFormLayout()
       formLayout.addRow(self.tr("Device:"), self.deviceLineEdit)
       formLayout.addRow(self.tr("P&itch:"), self.pitchSlider)
       formLayout.addRow(self.tr("&Volume:"), self.volumeSlider)

       buttonLayout = QVBoxLayout()
       buttonLayout.addWidget(self.playButton)
       buttonLayout.addStretch()

       horizontalLayout = QHBoxLayout(self)
       horizontalLayout.addLayout(formLayout)
       horizontalLayout.addLayout(buttonLayout)

   def changeFrequency(self, value):

       self.frequency = 440 + (value * 2)

   def play(self):

       if self.output.state() == QAudio.ActiveState:
           self.output.stop()

       if self.buffer.isOpen():
           self.buffer.close()

       self.createData()

       self.buffer.setData(self.data)
       self.buffer.open(QIODevice.ReadOnly)
       self.buffer.seek(0)

       self.output.start(self.buffer)

   def changeVolume(self, value):

       self.volume = value

   def createData(self):

       # Create 2 seconds of data with 22050 samples per second, each sample
       # being 16 bits (2 bytes).

       self.data.clear()
       for i in xrange(2 * 22050):
           t = i / 22050.0
           value = int(self.volume * sin(2 * pi * self.frequency * t))
           self.data.append(struct.pack("<h", value))

if name == "main":
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())

[SGaist]

Hi and welcome to devnet,

That should more likely be PyQt5.

[sahil713]

@SGaist I am new to pyqt and qt programming. This example was given in a python website. Here's the link:

Playing a sound with QtMultimedia

However i tried using Pyqt5 but there is this error.

Edit:

I tried solving this error.

ImportError: cannot import name QApplication

QApplication is in QtWidgets module so it should be

from PyQt5.QtWidgets import QApplication

But now I get this error

AttributeError: 'QAudioFormat' object has no attribute 'setChannels'

[sahil713]

This post is deleted!

[SGaist]

It's setChannelCount.

[sahil713]

@SGaist Thank you very much.

[SGaist]

You're welcome !

Since you have it working now, please mark the thread as solved using the "Topic Tools" button so that other forum users may know a solution has been found :)