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An SGH-tree based efficient
Huffman decoding
Yuh-Jue Chuang and Ja-Ling Wu,
Communications and Signal Processing
and the Fourth Pacific Rim Conference
on Multimedia, pp. 1483 - 1487 , 2003
Presenter :Yu-Cheng Cheng
Outline
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Introduction
Hashemian's Method
Aggarwal’s Method
The proposed approach
Experimental results
Introduction
• Huffman codes are being widely used in
image and video compression.
• Two intuitive Huffman decoding
approaches are the Bit-serial decoding
and the Lookup-table-based decoding.
Outline
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Introduction
Hashemian's Method
Aggarwal’s Method
The proposed approach
Experimental results
Hashemian's Method
• Hashemian presented an efficient Huffman
decoding algorithm based on alleviating
the affection of sparsity the Huffman tree.
• The main idea of HM is that by effectively
grouping the codewords within specified
codeword length.
Hashemian's Method
• HM needs to construct a special splay
Huffman tree called the single-side
growing Huffman tree (SGH-Tree).
Hashemian's Method
Fig.1 An example Huffman tree, in which the corresponding SGH-tree TI is of
height 5 and the 3 subtrees rooted at T1, T2 and T3 for HM.
Outline
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Introduction
Hashemian's Method
Aggarwal’s Method
The proposed approach
Experimental results
Aggarwal’s Method
Fig.2 (a) An Example Huffman tree and (b) the corresponding Huffman
Table of Fig.3 (a) for AM.
Aggarwal’s Method
Fig.3 The modified Huffman table of Fig.2
Outline
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Introduction
Hashemian's Method
Aggarwal’s Method
The proposed approach
Experimental results
The proposed approach
• An SGH-tree based AM algorithm
achieving efficient Huffman decoding.
The proposed approach
• Step1:
Construct an SGH-tree and the corresponding modified
Huffman table which is sorted according to “actlen” for
representing the source symbols.
• Step2:
Search for two subtrees s1 and s2 and swap them such
that the required memory size is decreased.
• Step3:
If the memory can not be reduced then Stop else go to
Step2.
The proposed approach
Fig.4 (a) An SGH-tree embedded Huffman tree. (b) The corresponding Huffman
table of Fig4(a).
Outline
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Introduction
Hashemian's Method
Aggarwal’s Method
The proposed approach
Experimental results
Experimental results
Table1. The comparison of the memory waste of Huffman tables among
MPEG-4, SGH-based and our proposed Huffman tree.