1 A JPEG-LS Based Lossless/Lossy Compression Method for Two-Dimensional Electrophoresis Images Source: 2003 International Conference on Informatics, Cybernetics, and Systems Authors: Kevin I-J Ho, Tung-Shou Chen, Hui-Fang Tsai, Mingli Hsieh, and Chia-Chun Wu Speaker: Chia-Chun Wu ( 吳佳駿 ) Date: 2004/12/09
NCHU 2 Outline Introduction Introduction Schema Schema Compression Method Compression Method Decompression Method Decompression Method Results Results Conclusion Conclusion
NCHU 3 We use Lossless and Near-Lossless compress the important areas and unimportant areas in Two-Dimensional Electrophoresis (2D-Gel) images. Our system improves traditional JPEG-LS to enhancing the compressed image quality. Introduction
NCHU 4 Schema (1/2) Compression flow chart 3 Original 2D-Gel Image Detect Protein ’ s Areas 1 Record Boolean Value of Important Areas 2 JPEG-LS Near-Lossless Compress 5 4 Write Difference Value of Original Image’s Important Areas Difference value Record File Near-Lossless Compressed File
NCHU 5 Decompression flow chart Add Difference to Image’s Pixel Value Add Difference to Image’s Pixel Value Keep Important Information of 2D-Gel Image JPEG-LS Near-Lossless Decompress Near-Lossless Compressed File Difference value Record File Near-Lossless Decompressed 2D-Gel Image Schema (2/2)
NCHU 6 Compression Method (1/5) Original 2D-Gel image - This is an original 2D-Gel image. X-axis represented the PH value of protein and Y-axis represented the amount molecular weight. Fig. 1 Original 2D-Gel image X-axis Y-axis
NCHU 7 Compression Method (2/5) Fetching protein’s area. - To collect the important protein ‘s areas of 2D-Gel image. The colourful areas will treat as important areas, and white areas will treat as unimportant areas. Fig. 2 The important part of 2D-Gel image
NCHU 8 Compression Method (3/5) Transform the important parts to Boolean value - Boolean value True(1) represents important areas, whereas False (0) represents unimportant areas. Fig. 3 Boolean value record file of important part
NCHU 9 Compression Method (4/5) Image after JPEG-LS Near-Lossless compression - This is an 2D-Gel image after traditional JPEG-LS Near-Lossless compression. Fig. 4 Image after JPEG-LS Near-Lossless compression
NCHU 10 Compression Method (5/5) Difference value records important part - The difference value of 2D- Gel image via the original image and lossless compression will store in a record file. Fig.5 Difference value record file
NCHU 11 Compression Example Original 2D-Gel Image Image after JPEG-LS Near-Lossless compression Difference value record file - =
NCHU 12 Decompression Method (1/3) Fig 6.Image after JPEG-LS Near-Lossless compression The image of Near-Lossless decompression - This is a decompressed image after traditional JPEG-LS Near- Lossless compression
NCHU 13 Decompression Method (2/3) Modify the protein’s area of important part - Next, we base on the difference value of pixels for modifying the protein’s area of important parts. Fig. 7 Difference value record file
NCHU 14 Decompression Method (3/3) Fig. 8 Our system’s lossless compression of important part. The lossless image of our system’s important areas - This complete 2D-Gel image is though traditional JPEG-LS Near-Lossless compression technique
NCHU 15 Decompression Example Image after JPEG-LS Near-Lossless compression Difference value record file Our system’s lossless compression of important part + =
NCHU 16 Results (1/4) Fig. 9 Partial magnify image of original 2D-Gel image Fig. 9 is the result of the amplification of dotted frame in Fig. 1.
NCHU 17 Fig. 10 Partial magnify image of traditional JPEG-LS. Results (2/4) Fig.10 is the result of the amplification of dotted frame in Fig. 4.
NCHU 18 Fig. 11 Partial magnify image of our system. Results (3/4) Fig. 11 is the result of the amplification of dotted frame in Fig. 8.
NCHU 19 Result (4/4) Table 1. The Comparison of image quality in traditional JPEG-LS Near-Lossless with our system (PSNR value). Unit:dB Results (4/4)
NCHU 20 Conclusion We store the unimportant areas by Near-Lossless method. But we store important areas by Lossless method. It is very important to medical images. Under different lossless level, we can find out our system has better image quality than traditional JPEG-LS. Therefore, how to compress the size of record file and detect the protein’s location more correctly becoming an important topic in the future.