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Optimal Selective Huffman
Coding for Test-Data
Compression
Kavousianos X., Kalligeros E. and Nikolos D.
Computers IEEE Transactions on,
pp. 1146 - 1152 , 2007
Presenter :Yu-Cheng Cheng
Outline
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Introduction
Selective Huffman encoding
Proposed selective Huffman encoding
Experimental result
Introduction
• Huffman codes are being widely used in
image and video compression.
• Compression is achieved by encoding the
most frequently occurring blocks with short
codewords and the less frequently
occurring ones with long codewords.
Outline
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Introduction
Selective Huffman encoding
Proposed selective Huffman encoding
Experimental result
Selective Huffman encoding
Table 1. Test Data Partitioning and Occurrence Frequencies
Selective Huffman encoding
Fig. 1. The Huffman tree of Example 1 and Selective Huffman encoding
Outline
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Introduction
Selective Huffman encoding
Proposed selective Huffman encoding
Experimental results
Proposed selective Huffman
encoding
• The occurrence frequency of the latter
codeword is equal to the sum of the
occurrence frequencies of all the
unencoded distinct blocks.
Proposed selective Huffman
encoding
Fig. 2. Proposed Selective Huffman encoding.
Proposed selective Huffman
encoding
• The compression ratio in this case is equal
to 38.8 percent .
Outline
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Introduction
Selective Huffman encoding
Proposed selective Huffman encoding
Experimental result
Experimental result
Table 2. Compression Ratios (%) Achieved by [8] and the Proposed Encoding