Mosquito noise is ringing in motion - a shimmering swarm of small specks that flickers and crawls around a moving high-contrast edge, changing every frame like mosquitoes hovering around a lamp. The mechanism is the same Gibbs-phenomenon ripple, but because the codec re-solves a moving edge from scratch each frame - a different sub-pixel position, a different fall across the block grid, a different motion-compensated prediction - the overshoot-and-ripple pattern lands in a slightly different place each time, and the eye integrates the jitter as a crawling cloud. It is worst on high-contrast edges over calm backgrounds: scrolling subtitles, an animated logo, line art and screen content. The defining catch is that mosquito noise is temporal, so any measurement that scores one frame in isolation is structurally blind to it; per-frame PSNR, SSIM, and VMAF miss the flicker, and mean-pooling buries it further. Catch it with low-percentile temporal pooling, a no-reference edge-busyness detector, or by watching the clip move.
The handbook · 7 volumes
Fora Soft Video Engineering Handbook
Mosquito noise shimmers around moving edges and text, and it often survives higher bitrates because it comes from how high frequencies are quantized. We wrote seven volumes covering the whole video stack, and for mosquito noise start with Volume 1: transforms and quantization, ringing, in-loop filters and artifact metrics. Written by Nikolay Sapunov, CEO at Fora Soft.
Mosquito noise around graphics and text even at decent bitrates?
Send us affected clips and your encoder config: we trace the mosquito noise and give you encoder and filter settings that reduce it. 250+ video products shipped since 2005.
