Fig. 1. Histogram modification
Fig. 2. Six types of block
Fig. 3. overlapped block
Fig. 4. Result of block classification (a) image (b) classification result
Fig. 5. Histogram modification of blocks (a) Histogram modification of Fig.1.(a)(b) Histogram modification of Fig.1.(d) (c) Histogram modification of Fig.1.(f)
Fig. 6. Result of dynamic range compression
Fig. 8. Result image (a) Original image (b) HE (c) PHE (d) GHM (e) CLAHE (f) Proposed algorithm
Fig. 9. Result image (a) Original image (b) HE (c) PHE (d) GHM (e) CLAHE (f) Proposed algorithm
Fig. 10. Result image (a) CLAHE (b) Proposed algorithm
Fig. 7. (a) Example of block artifact (b) Result of reduction block artifact
Table 1. Value of Entropy
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