Use an image color extractor to inspect several pixels in the area you care about. Photos contain lighting, shadows, texture, and compression noise, so one pixel may not represent the perceived color.
If you need a design swatch, compare a small region or several nearby samples and choose a value that looks right against the intended background. Convert it to HEX, RGB, or HSL as required, but remember that a color name is approximate. Check the displayed result after export; color profiles can shift appearance between applications.
Keep the original image and note where the sample came from.
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