# system: ffmpeg (libx264, aac, libmp3lame; filters loudnorm, ebur128, silencedetect, astats)
numpy
scipy
soundfile
librosa          # beat tracking and audio features for music-driven films
edge-tts         # default TTS (needs network access to speech.platform.bing.com)
faster-whisper   # narration check; pre-download models: Systran/faster-whisper-base.en, Systran/faster-whisper-small