Гул Земли 2 (Earth Rumble 2)

Platform: hackerlab | Category: Forensics | Type: Challenge | Difficulty: Easy | OS: Windows | Author: XESXOR | Date: 2026-01-06 | Status: Solved Techniques: sstv_decoding, robot36_mode

Summary

Files: earth rumble 2.zip -> task.wav

Гул Земли 2 (Earth Rumble 2) - Hackerlab

Description

Возможно этот радиосигнал был получен из космоса. Или нет? (Perhaps this radio signal was received from space. Or not?)

Files: earth rumble 2.zip -> task.wav

Analysis

File Identification

 bash read-only • copy allowed Copy
file task.wav
# RIFF (little-endian) data, WAVE audio, Microsoft PCM, 16 bit, mono 44100 Hz

Standard WAV file, mono, 16 bit, 44100 Hz.

Key Hints

1. Task name: "Гул Земли" (Earth Rumble/Hum) - reference to radio signals
2. Description: "radio signal from space" - clear hint at SSTV
3. Format: Mono audio - typical for SSTV signals ‍​‌‌​​​​‌​‌‌​​‌‌​​‌‌​​‌‌​​‌‌​​‌​​​​‌‌​​​​​‌‌​​‌‌​​‌‌​​‌​‌​‌‌​​‌​‌‍

What is SSTV?

SSTV (Slow Scan Television) - method of transmitting images via radio signals:

• Used by amateur radio operators since the 1950s
• Applied in space missions (Apollo, ISS)
• Image is encoded as an audio signal with various frequencies
• Multiple modes exist: Robot 36, Scottie, Martin, etc.

Solution

Decoding the SSTV Signal

 python read-only • copy allowed Copy
#!/usr/bin/env python3
from sstv.decode import SSTVDecoder

# Decode WAV file
decoder = SSTVDecoder('task.wav')
img = decoder.decode()

# Save the result
if img:
    img.save('output.png')
    print("Image decoded successfully!")
else:
    print("Failed to decode SSTV signal")

‍​‌‌​​​​‌​‌‌​​‌‌​​‌‌​​‌‌​​‌‌​​‌​​​​‌‌​​​​​‌‌​​‌‌​​‌‌​​‌​‌​‌‌​​‌​‌‍

Decoding Result

The decoder automatically detected Robot 36 mode and successfully extracted the image.

The decoded image contains:

• An image of a UFO abducting a cow
• Flag text at the bottom of the image

Alternative Tools

• QSSTV (Linux) - GUI application for SSTV decoding
• MMSSTV (Windows) - popular SSTV decoder
• Robot36 (Android) - mobile application
• RX-SSTV - online decoder

SSTV Modes

References

• SSTV Wikipedia
• Python SSTV Library ‍​‌‌​​​​‌​‌‌​​‌‌​​‌‌​​‌‌​​‌‌​​‌​​​​‌‌​​​​​‌‌​​‌‌​​‌‌​​‌​‌​‌‌​​‌​‌‍