Secure Layer Based Compound Image Compression using XML Compression Author ： D. Maheswari 1, V.Radha Source ： Computational Intelligence and Computing Research (ICCIC), 2010 Advisor ： Wen-Jan Chen Speaker ： Hui-chun Su

Outline Introduction Methodology Experimental result Conclusion

Introduction Digital image compression ▫Reduction to save storage space ▫Reduce transmission rate requirements Compound images ▫Computer generated images (CGI) ▫Text images (TI) ▫Scanned images (SI) ▫Document images (DI) CGI TI SI DI

Introduction Compressing compound images ▫Single algorithm  Elusive data types ▫Segmentation data  Similar data types  Lowers the bit rates  Lowers the level of distortion

Introduction Segmentation algorithms ▫Object-based ▫Block-based ▫Layer-based XML Compression for Compound Images(XMLCC) ▫Compression ▫Secure transmission

Introduction The work’s three phase ▫MRC based segmentation  Foreground (FG)  Background (BG)  Mask ▫Compressed  FG using XML compression  BG using JPEG ▫Secure transmission

Outline Introduction Methodology Experimental result Conclusion

Methodology MRC segmentation Pre processing Block transformation Compression Encryption

Methodology MRC Segmentation ▫Foreground (FG)  Textual elements ▫Background (BG)  White space and picture elements ▫Mask  Binary mask  Pixel's state

Methodology Pre processing ▫Halo effect  Layer based technique ▫Data filling algorithm  Enhance compression.

Methodology Block transformation ▫Rearranges the image data  Step 1. matrix transpose  Step 2. clockwise rotation  Angle θ  Step 3. flips the matrix  Horizontally(rows) and vertically(columns)  Step 4. converting pixel values  Adding a value in odd and even columns (8 and 4)  Step 5. stores two separate images (odd and even)

Methodology Block transformation ▫Step 1. matrix transpose

Methodology Block transformation ▫Step 2. clockwise rotation

Methodology Block transformation ▫Step 3. flips the matrix (horizontally)

Methodology Block transformation ▫Step 3. flips the matrix (vertically)

Methodology Block transformation ▫Step 4. converting pixel values

Methodology Block transformation ▫Step 5. stores two separate images (odd and even) Odd columnsEven columns Original image

Methodology Compression ▫FG layer : using an XML compressor  XML-specific compression tool as called Xmill  Separate structure from data  Group related data items  Apply semantic compressors ▫BG layer: using JPEG 2000

Methodology Encryption ▫Insure security ▫Shuffle Encryption Algorithm

Outline Introduction Methodology Experimental result Conclusion

Experimental result The system was compared with compression ratio, time and PSNR values. All the experiments were conducted using a Pentium IV dual processor with 512 MB RAM. All the images were of the size 256x 256 pixels.

Experimental result

CT : compression time DT : decompression time

Outline Introduction Methodology Experimental result Conclusion

Higher compression Lower distortion Security for image data transferred