Introduction to SNG and ENG Microwave

MPEG picture problems

Artefacts

When pushed to the limit, compression processes can produce visual defects, termed ‘artefacts’.

These include a pixellation effect commonly referred to as ‘blockiness’, momentarily showing as rectangular areas of picture with distinct boundaries. Other artefacts may be seen near the edges of objects, such as blurring caused by reducing horizontal and/or vertical resolution. However, one of the most commonly seen problems is colour quantization error, often obvious on smooth areas of changing colour shade, where there are seen to be distinct bands marking the transition from one shade to another of a similar hue.

Delay and latency

Delay through a compression process is termed latency, and latency is of particular ...