BPCS steganography using EZW lossy compressed images

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BPCS steganography using EZW lossy compressed
images

• Source Pattern Recognition Letters,Vol.
  23,2002,pp.1579-1587
• Author Jeremiah Spaulding, Hideki Noda, Mahdad
  N. Shirazi, Eiji Kawaguchi.
• Date 2002/10/24
• Speaker Chi-Shiang Chan

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Outline

• Bit-Plane Complexity Segmentation (BPCS)
• Wavelet compression
• BPCS steganography combined with EZW
• Experimental Results

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Bit-Plane Complexity Segmentation (BPCS)

• Bit-Plane Complexity
• Secret Data Hiding

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Bit-Plane Complexity Segmentation (BPCS) ---
Bit-Plane Complexity

• Bit-Plane Complexity the number of non-edge
• transitions from 1 to 0 and 0 to 1
• (both horizontally and vertically)

Bit-Plane Complexity 2
Bit-Plane Complexity 12
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Bit-Plane Complexity Segmentation (BPCS) ---
Secret Data Hiding

• Secret Data Hiding

• Segment the secret data into a series of blocks.
• Segment a image into the same size of blocks.
• If a secret block is less more complex than
  threshold
• ( 0.3 ) conjugation it to
  make it more complex.

Exclusive OR

( 10)
4. If a image block is more complex than
threshold, replace it with a block of
secret.
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Wavelet compression
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Wavelet compression
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BPCS steganography combined with EZW-- Embedding
Secret Data

• Embedding Secret Data

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BPCS steganography combined with EZW-- Embedding
Secret Data

• Complexity threshold

total number of bit-plane.
total number of scales in wavelet transform.
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BPCS steganography combined with EZW-- Embedding
Secret Data

• Complexity threshold--Example

Number of Bit-plane6
The threshold of the first bit-plane
The threshold of the first bit-plane
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BPCS steganography combined with EZW-- Extracting
Secret Data

• Extracting Secret Data

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Experimental Results--Lena
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Experimental Results--Lena
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Experimental Results--Barbara
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Experimental Results--Barbara