Introduction
You might think images and audio belong to completely different worlds—but what if you could send a picture as sound? That’s exactly what happens with a fascinating method called SSTV (Slow Scan Television), used since the 1950s. Let’s explore how it works, and why it's still used today—even in space
What Is SSTV (Slow Scan Television)?
SSTV is a technique that converts an image into a series of audio tones. These tones can be played, recorded, or transmitted just like regular sound. A decoder can then listen to this "sound image" and reconstruct the original picture.
How It Works – Image to Audio
The image is scanned line by line.
Each pixel’s brightness or color is turned into a specific frequency.
The result is a sound file (e.g., .wav) that "sounds weird" to the ear—but it's carrying visual data.
How to Try It Yourself (Modern Use)
You can encode an image into audio using tools like:
*SSTV Encoders (online or desktop)
*
Save the audio and play it
Use an app like Robot36 (Android) to decode it back into an image
It's like a secret message hidden in sound!
SSTV in the Real World
Amateur Radio (HAM): Widely used to share pictures over radio.
NASA & ISS: The International Space Station transmits SSTV images to Earth.
Offline Communication: Works without the internet—ideal for remote or emergency scenarios
Why It’s Cool and Useful
1.Works with low tech—just a speaker and mic
2.Sends images where the internet can’t reach
3.Fun for hobbyists and retro tech fans
4.Teaches fundamentals of analog signal encoding
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