Tagged: whisper

RadioTranscriber: Real-Time Public Safety Radio Transcription with Whisper AI

Over in our new forums, user Nite has shared a new open-source project that he's created called RadioTranscriber, a real-time speech-to-text tool for public safety radio feeds using OpenAI’s Whisper large-v3 model. The idea is to take live scanner audio, such as authenticated streams from Broadcastify, and continuously turn it into readable text with minimal babysitting. The project grew out of earlier experiments with Radio Transcriptor, which we posted about back in June, but quickly evolved into a more robust, long-running setup with better audio conditioning and fewer of Whisper’s common hallucinations.

Under the hood, RadioTranscriber is a Python script that pulls in a live stream, cleans it up with filtering, normalization, and WebRTC VAD, then runs Whisper large-v3 with beam search for transcription. A set of custom “hallucination guards” strips out common junk text and replaces alert tones with simple markers, while daily log rotation and basic memory management let it run unattended for long periods, even on a modest CPU-only machine. Although it’s tuned to the author’s local dispatch style, the config and prompt are easy to adapt, and the full code is available on GitHub for anyone who wants to experiment or build on it.

How OpenAI's Whisper Works
How OpenAI's Whisper Works

RadioTransciptor: Real Time Radio Speech to Text Transcriptor using AI

Thank you to user theckid from our forums for submitting news about the release of his latest project called "RadioTranscriptor". RadioTranscriptor can be used for real-time speech-to-text transcription, which is especially useful when you want to log radio communications and create searchable text files. theckid writes:

I just released an open-source Python tool that does real-time radio transcription using OpenAI’s Whisper model. It uses voice activity detection to only transcribe when speech is actually happening — great for monitoring radio chatter or voice nets on HF/VHF/UHF.

It’s designed for use with SDRs (Software Defined Radios) where audio is routed into the script. It performs:

  • Live microphone or SDR audio monitoring
  • RMS-based voice activity detection (VAD)
  • Automatic transcription with Whisper
  • Timestamped logs saved per session
  • It’s perfect for:
  • Ham radio operators
  • Emergency scanners
  • Broadcast archiving
  • Signal analysis enthusiasts

The AI model used is Whisper by OpenAI. The software uses NVIDIA CUDA GPUs when available and defaults back to CPU if none are available.

RadioTranscriptor Block Diagram
RadioTranscriptor Block Diagram