Lossless Compression of 3D Medical Images Using its Symmetry

Now days 3D medical images like MRI, CT are integral part of standard health care. These images are rich in volume and provide important diagnostic information, so there should be some proper method to compress these images. The method proposed in this paper is symmetry based technique for lossless compression of 3D medical image data. The proposed method uses 2D integer wavelet transform to decorrelate the data and block based intra-band prediction which uses anatomic symmetries present in structures of medical images to reduce energy of sub-bands. This method exploits the global and local symmetries of the wavelet transform sub-bands based on the main axis of symmetry. It uses Embedded Block Coder with Optimized Truncation (EBCOT), which encodes the residual data generated after prediction to provide resolution and quality scalability. The technique can be compared with other compression techniques like 3D JPEG2000, JPEG2000, and H.264/AVC and it gives an average improvement in compression ratios.