Low Level Noise

    Low level noise is noise in the black part of the image. Instead of deep, clear and crisp blacks, blacks appear grainy due to random noise inserted into the luminance (black and white information) signal. Whilst this type of artefact affects all shades of grey in the final image, it is far more noticeable in darker portions of the image.

    Low level noise is particularly problematic for analogue video sources - true black is simply not possible on VHS because of it, and to a lesser extent on laserdisc. Properly mastered DVDs utilizing all-digital production methods are largely immune to this artefact.

    Increased MPEG macro-blocking artefacts are a potential side-effect of low level noise, as the MPEG encoder attempts to encode the extra spurious random noise, leaving less bits for actual picture information.

Les Miserables-The Dream Cast 19:32

Instead of being a clean, deep black, the background of this image is marred by random video noise.