A palette can help choose supporting design colours from a photo. It is an approximation of visible colour distribution, not a list of every exact colour in the original file.
Image Colour Palette samples a bounded image and counts quantised RGB colour bins. Choose how many of the most common entries you want to display.
A bin represents a range of colours
The sample is at most 128 by 128 pixels. Nearby RGB values are grouped, and the reported HEX values represent bin centres rather than necessarily matching a source pixel exactly.
For example, strong red values can contribute to a bin shown near #F01010. That should not be interpreted as proof that the original contains a large flat area painted with precisely that HEX value.
The displayed percentages describe counted visible sample pixels. Fully transparent pixels are excluded, so an empty transparent background does not become a dominant visible colour by itself.
Small details can disappear in the sample
A thin brand stripe or a small highlight may not rank among the most common bins. If you need the exact value at a known coordinate, use the Pixel Colour Picker instead.
A palette does not establish accessible foreground and background contrast. Two attractive colours taken from the same image may still be difficult to read together.
Compare several proposed palette colours against the actual asset and intended page background. The most common sampled colour is not automatically the best button, heading or text colour.
Keep the palette as a design reference with its sampling limitation. For a precise brand specification, use the organisation's approved colour values rather than replacing them with an approximate result from a photograph.