3D Medical Images Compression

Image Compression

Image compression is the appliance of data compression on digital images which are made up of large number of pixels. Compression is the reduction in the amount of image data (the number of bytes) while preserving information (image details) with the intention of optimizing and putting to maximum use the data storage and data transmission facilities. Images transmitted over the internet are an excellent example of why data compression is important. Suppose we need to download a digitized color photograph over a computer's 33.6 kbps modem. If the image is not compressed (a TIFF file, for example), it will contain about 600 kilo bytes of data. If it has been compressed using a lossless technique (such as used in the GIF format), it will be about one-half this size, or 300 Kbytes. If lossy compression has been used (a JPEG file), it will be about 50 Kbytes. The download time for these three equivalent files are 142 seconds, 71 seconds, and 12 seconds, respectively which is a huge difference.

The following table (Table 1) shows the qualitative transition from simple text to full-motion video data and the disk space transmission bandwidth, and transmission time needed to store and transmit such uncompressed data (Sachin Dhawan, 2011).