Skip to content

Perceptual coding

Definition

Lossy compression that exploits psychoacoustic or psychovisual masking to discard information the human senses are least sensitive to. MP3, AAC, and AC-3 audio codecs all use this approach, producing spectral artefacts that persist through subsequent conversions.

Related terms

Codec
A coder/decoder algorithm that compresses and decompresses media data. H.264/AVC and H.265/HEVC are the dominant video codecs; AAC and MP3 are dominant...
Container format
A file format (MP4, MKV, MOV, AVI, MXF) that multiplexes video, audio, and metadata tracks into a single file with a defined...
GOP (Group of Pictures)
The repeating sequence of I, P, and B frames in an inter-frame compressed video. GOP size (the distance between I-frames) is an...
I-frame
An intra-coded frame: a self-contained image compressed without reference to any other frame, like a JPEG. I-frames are the only random-access entry...
Rewrapping
Moving a compressed bitstream from one container to another without decoding it. Forensically equivalent to the original encoded stream; no new generation...

Explained in

Your journey to becoming a forensic professional starts here.

Practice with mock tests, learn from structured notes, and get your questions answered by a global forensic community, all in one place.