Visual Saliency Analyzer

Explore how different visual properties make regions of an image attract attention. Load an image, and see which areas are most visually salient and why.

← Back to Compression Concepts Video compression comparison

What Drives Visual Attention?

Properties that increase visual saliency

  • Luminance Contrast — Bright regions against dark backgrounds (or vice versa) draw the eye
  • Color Contrast — Colors that differ from their surroundings pop out (red among green)
  • Edge Density — Areas rich in edges and detail attract attention over smooth zones
  • Orientation Contrast — A tilted element among uniform orientations stands out
  • Saturation — Vivid, saturated colors among muted tones grab focus
  • Center Proximity — Centrally located regions naturally attract more attention
  • Regional Color Contrast — Regions whose color differs from surrounding regions stand out
  • Foreground / Background — Foreground objects are weighted as more salient than background
  • Shape Unusualness — Irregular or unusual shapes draw attention over regular forms

Saliency Analyzer

Load an image from your file system or choose a sample, then analyze its visual saliency.

or pick a sample:
256
20

Original Image

Saliency Overlay

Low
High

Region Inspector

Individual Feature Maps

Each map highlights regions that stand out for a specific visual property. Adjust weights to control their influence on the combined saliency.

Video Saliency

For video, attention is also driven by motion and temporal change. Load a short clip to see how temporal factors layer on top of the static saliency properties.

Additional saliency factors for video

  • Temporal Contrast — Regions that change significantly between consecutive frames immediately attract the eye
  • Flicker — High temporal luminance variance (rapid oscillating changes) signals unstable or flickering regions
  • Motion Boundary — The spatial edges where moving regions meet static ones are especially salient — the visual system uses these to segment objects
  • Moving Foreground — Objects that deviate from the time-averaged background model are treated as foreground and weighted more highly
  • Luminance Contrast (Static) — Center-surround luminance contrast from the selected frame, identical to the image saliency factor
Foreground & background segmentation approach: The background model is estimated as the per-pixel mean across all extracted frames. Any frame pixel that deviates substantially from that mean is classified as moving foreground. This is robust to gradual illumination shifts and works even on short clips where only part of the scene is in motion. Motion boundaries are then derived by computing the spatial gradient of the smoothed temporal-contrast map, isolating the contours between moving and static regions.
12
60%