Borrowed from military radio, this method spreads the secret signal across a wide range of frequencies, making it look like background noise. It's extremely resistant to tampering and compression but very hard to implement without detection.
Marcus hit the print screen button, capturing the image, and then yanked the hard drive out of his computer. He reached for the secure phone on his desk, his hand trembling slightly. audio stego
He switched tactics. He ran the file through a high-pass filter, stripping away the low rumbles. Then, he applied a phase inversion. Still nothing but snow on the screen. Borrowed from military radio, this method spreads the