pyqt-multimedia

Objective: Use this skill to reduce playback-deadlock incidents, GStreamer-backend startup failures, codec-missing black-screen bugs, and recording-corruption incidents by enforcing backend-setup discipline, codec-availability checks, and platform-compatibility decision patterns below.

Core Rules (do X because Y)

Check GStreamer plugins before playback because missing codecs produce silent black video

On Linux, Qt Multimedia uses GStreamer as the backend. Missing plugins cause video to render as black screens without errors.

# Ubuntu/Debian - install ALL plugin groups before testing playback
sudo apt-get install libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev \
    gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly \
    gstreamer1.0-libav

# Verify plugins are loaded
gst-inspect-1.0 | grep -E "h264|mp3|aac"