Image histogram
Visualizes the tonal distribution across R/G/B and luminance channels with median, mean and clipping percentages.
Computes a histogram across four channels: red, green, blue and luminance (Y per ITU-R BT.709, the sRGB standard). Below the chart, a table shows mean, median and the percentage of pixels clipped in the shadows (value 0) and highlights (value 255) for each channel — so you can see whether detail was lost in the darkest or brightest areas during capture or processing. Two render modes — overlay (Photoshop-style, four channels on a single chart with alpha blending) and stacked (four charts one below the other, each auto-scaled) — and two scales — linear and logarithmic (log1p): the log scale makes rare tones and gaps from aggressive levels adjustments easier to see. A purely visualizing tool — no file output, nothing leaves your device.