SSTV Radio Decoder & Encoder

📻 Send and Receive Images Over the Air! 🛰️
Turn your Android device into a powerful Slow Scan Television (SSTV) communications hub! Designed specifically for amateur radio (ham radio) operators, shortwave listeners (SWLs), and emergency communicators, this application allows you to seamlessly decode and encode images using standard radio audio tones.

Whether you are tuning into high-frequency (HF) bands, listening to local VHF/UHF repeaters, or tracking the International Space Station (ISS) for specialized downlinks, this tool provides the precise digital signal processing (DSP) needed to render clean, high-resolution images. 📸

🚀 Core Features
📺 Real-Time Audio Decoding: Place your phone's microphone near your transceiver's speaker or use a direct line-in patch cable to watch images draw on your screen line by line.

⚡ High-Quality Signal Encoding: Convert any image from your gallery or live camera into standard SSTV audio frequencies, ready to transmit over your radio equipment.

🤖 Auto-Mode Detection: No more manual guessing! The app automatically listens for the VIS calibration header to instantly identify and switch to the correct incoming transmission mode.

📐 Slant Correction: Easily correct timing misalignments and slant anomalies caused by device clock differences to straighten your received images perfectly.

📊 Audio Spectrum Analyzer: A built-in waterfall display helps you center, align, and monitor incoming audio frequencies in real time.

🧬 Supported SSTV Modes
The app features wide compatibility across standard analog operational modes used globally by the amateur radio community:

🤖 Robot Modes: Robot 36, Robot 72

🏴󠁧󠁢󠁳󠁣󠁴󠁿 Scottie Modes: Scottie 1, Scottie 2, Scottie DX

🎩 Martin Modes: Martin 1, Martin 2

🌀 Wraase Modes: SC2 180

📱 Optimized for Mobile & Field Use
🔋 Battery Efficient: Low-overhead processing ensures your phone won't die during long monitoring sessions, emergency deployments, or ARRL Field Days.

🌙 Clean UI/UX: Full dark mode optimization ensures perfect readability in low-light radio shacks or during night operations.

🛠️ Built-in Image Editor: Crop, adjust contrast, and add custom callsign text overlays to your images directly inside the app before broadcasting.

⚠️ Note: A valid amateur radio license is required to transmit radio signals. Sideloading audio into a transceiver requires appropriate hardware or interface cabling (like a SignaLink or custom audio interface) for clean, undistorted transmission.

Recent changes:
Fixed bugs, improved app performance