Building an AI Profanity Filter with Vocal Separation

I built an online tool that automatically detects and bleeps profanity in video and audio files. Here's the high-level architecture.

The problem

Manual profanity censoring takes 45+ minutes for a 10-minute video. You have to listen through, find each word, razor the audio, drop a beep effect. For songs, it's nearly impossible without destroying the music.

The solution

AI speech recognition + neural vocal separation.

How it works

1. User uploads a file or pastes a YouTube URL


2. Audio is extracted with FFmpeg


3. AI speech-to-text transcribes the audio (AssemblyAI / Deepgram)


4. Profanity is detected using morphological analysis (lemmatization)


5. Each word is replaced with beep/silence/custom sound via FFmpeg


6. For songs: Demucs AI separates vocals from instruments first

Song mode — the hard part

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Would love to hear your thoughts!