Qt is a widely adopted GUI framework, but its documentation is quite awful, especially when working in Python. And it's likely that you get the error
QSoundEffect(qaudio): Error decoding source /path/to/the/filetext
when trying to play some sound effects with Qt. This error message is quite misleading. Apart from the obvious circumstance that the audio file is broken, there might be some other causes.
Cause 1: You are trying to play an MP3 file #
MP3 files are not supported. You can convert the MP3 file to a WAV file:
ffmpeg -i ding.mp3 ding.wavsh
Cause 2: You are passing the path, not URL #
QSoundEffect.setSource is expecting an URL, not a Path or str. So any one of these works:
self.soundEffect.setSource(
QtCore.QUrl.fromLocalFile(Path(__file__).parent / "ding.wav")
)
self.soundEffect.setSource(QtCore.QUrl.fromLocalFile("./ding.wav"))
self.soundEffect.setSource("file:./ding.wav")python
But none of these works:
self.soundEffect.setSource("ding.wav")
self.soundEffect.setSource(str(Path(__file__).parent / "ding.wav"))python
Appendix: Full code #
import sys
from pathlib import Path
from PySide6 import QtCore, QtMultimedia, QtWidgets
class MyWidget(QtWidgets.QWidget):
def __init__(self, parent=None) -> None:
super().__init__(parent)
mainLayout = QtWidgets.QVBoxLayout(self)
self.soundButton = QtWidgets.QPushButton(text="Play")
mainLayout.addWidget(self.soundButton)
self.soundEffect = QtMultimedia.QSoundEffect()
self.soundEffect.setSource("file:./ding.wav")
self.soundEffect.setLoopCount(3)
self.soundButton.clicked.connect(self.soundEffect.play)
if __name__ == "__main__":
app = QtWidgets.QApplication([])
widget = MyWidget()
widget.resize(200, 100)
widget.show()
sys.exit(app.exec())python
Thanks for the instructions, @AllanChain. At least, the sound (with a start delay of 5 seconds) is playing, but I am receiving errors:
For your code in the "Appendix: Complete code", I also receive this. The MP3 sound is received as:
My ffmpeg version:
. How can I fix or suppress these issues?