Each assigned local thumbnail is reduced to a 32 by 32 pixel sample, preserving its whole image. Transparent pixels are composited over white. The original picture is still displayed without recolouring.
A consistent pixel rule
Samples below 0.16 saturation or 0.18 brightness are neutral. The remaining samples use six hue bins: red, orange, yellow, green, blue and purple. A coloured label needs at least 40% coloured samples and a leading bin with at least 45% of coloured samples.
Neutral and ungrouped
If fewer than 40% of samples are coloured, the preview is neutral. If no hue bin reaches the leading threshold, it is ungrouped. Neither condition is an error or a game-quality judgement.
Use All for source categories
Colour belongs to this preview index. The original game categories remain unchanged and are independently available in All games. A colour never proves a game setting, genre, mechanic or accessibility characteristic.