A No-Reference Sharpness Metric Based on Structured Ringing for JPEG2000 Images

Figure 3

Typical samples demonstrating the ringing refinement. (a) An image with moderate ringing artifacts. The ringing artifacts appear around strong edges. ((b) and (c)) The preliminary and final ringing maps. (d) An image with another type of “ringing.” It occurs at tiny structures under high compression. ((e) and (f)) The preliminary and final ringing maps. (g) An image with severe blurring artifacts. In the image, the ringing artifacts are concealed by the blur. ((h) and (i)) The preliminary and final ringing maps. (j) A sharp image with no compression. ((k) and (l)) The preliminary and final ringing maps.

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