Blur detection for focused images

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Blur with Laplacian method returns and indirect measure of Blur. It's relative to the image context therefore you can't set absolute bias.

If you compare values from same subject one focused other out of focus you can get best focused using Laplacian method.

BTW your image contains large blurred area (background) that reduces the "Laplacian focus score".

• You might preprocess the image to separate the background from foreground than evaluate the "Laplacian focus score" only on foreground.
• As 2nd way you might calculate local "Laplacian focus score" maybe split the image in 3x3 sub-images, calculate your score for each sub-image. Maybe central sub-images are the foreground and give you better results.