COMPRESSION PREPARED BY:UNDERGUIDANCE NISHA RAJANI (01)OF : PARAMJEET SINGH JAMWAL (07) PARAS PRATEEK BHATNAGARMr. A. S. YADAV (08)Mr. A. SHUKLA PREETI KUMARI (12)
Contents …Why We Opted For This Project & Our Aim ?What is IMAGE COMPRESSION & Its Benefits ?MEDICAL IMAGE COMPRESSION & Differences .What is JPEG Compression?Our Results of IMAGE COMPRESSION Using DCT .Tasks Left In Our Project .Applications of MEDICAL IMAGE COMPRESSION .
Why we Opted For This Project ?Shortcomings of present IMAGE COMPRESSION methods : A large bandwidth is required for transmission . A large time is required for compression .Lack of perfect lossless method which could preserve dataOur Aim .Reduce the size & compression time of the image with leasteffect on its quality .
What is IMAGE COMPRESSION ? Application of data compression ondigital images Reduce redundancy in the image dataBenefits of IMAGE COMPRESSION . Store data efficiently Transmit data efficiently
MEDICAL IMAGE COMPRESSION . Production of visual representations of bodyparts, tissues or organs Used in clinical diagnosis Encompasses X-ray methods , MRI & CT ScanDifferences From Normal IMAGE .Significant information in a small area Monochromatic background colour .
What is JPEG Compression ? Stands for Joint Picture Experts Group Most popular LOSSY compression method Extensively used by digital cameras , mobiles & web usage Not suited for drawing , textual and iconic graphics Uses extensions – JPG or JPEG
Basics of JPEG Compression Human vision insensitive to Original high spatial frequencies image [ 150KB ] High frequencies more coarsely compressed & Frequency filtered Domain image Application of HPF Image stored as frequency JPEG data image [ 14KB ]
The JPEG Compression Algorithm Original image [ 150KB ] 8x8 RGB pixel To DCT Quantization Zigzag blocks YCbCr scan Huffman Encoding RLE JPEG Compressed Data [ 14 KB ] 100100010001000100100001111100010100
The JPEG Decompression Algorithm 100100010001000100100001111100010100 JPEG Compressed Data [ 14 KB ] Huffman Zigzag RLE To Quantization IDCT Decoding 8x8 Multiplication Matrix YCbCr Image To Reconstruction RGB Decoded image [ 150KB ]
Basic TERMS used : PSNR : Ratio between the maximum possible power of a signal and the power of its corrupting noise . MSE : The difference between an estimator and the true value of the quantity being estimated.
Basic TERMS used : CR : The reduction in data-representation size produced by a data compression algorithm. BITRATE : Number of bits that are used for representing a pixel .
Our Results of Normal Image using DCT Variation of Image Parameters with BITRATE 200 180 160 90 % 60 % 140 120 100 CR 80 MSE 60 PSNR 40 20 0 40 % 20 % 0 0.2 0.4 0.6 0.8 1 BITRATE PEPPERS IMAGE
Our Results of Medical Image using DCT Variation of Image Parameters with BITRATE 50 45 40 35 90 % 60 % 30 25 CR 20 MSE 15 PSNR 10 5 0 0 0.2 0.4 0.6 0.8 1 40 % 20 % BITRATE CAT SCAN IMAGE
Our Results of Medical Image using DCT Variation of Image Parameters with BITRATE 60 50 90 % 60 % 40 30 CR MSE 20 PSNR 10 0 0 0.2 0.4 0.6 0.8 1 40 % 20 % BITRATE X-RAY IMAGE
Tasks left in our project Image Compression using DWT , JPEG2000 & SPIHT RLE Coding using Arithmetic codingtechnique Comparison & conclusion about thebest method
Applications of Medical Image Compression Magnetic resonance imaging (MRI) Breast Thermography Tomography Ultrasound X-Rays Scientigraphy