After compressing an image, compare the exported copy with the original at normal size and 100% zoom. Look for ringing around high-contrast edges, block artifacts, banding in gradients, and blurred small text. Check dimensions, transparency, color appearance, and actual byte size. If the image is a screenshot or diagram, a lossless format may preserve clarity better than aggressive lossy compression. Keep the original and do not accept a smaller file if key detail becomes unreadable.
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