The input compressed image consists of a collection of 4 x 4 compressed image block bit planes and their respective means, standard deviations and chosen thresholds packed into a 13 byte Mars Pathfinder Rover image data package. There is an optional keyword that can be specified to have the internal calculations and decompressed image block data printed to standard output. Natural log of variance of third block. The following are definitions of keywords to be used in the image labels to describe the data compression used.
Blocks are rectangular areas of input.
Each block of data is compressed separately. For example, a compression ratio of 5.00 means that on average, for every five bytes of input data, one byte of compressed data was generated by data compression. The mode of compression is either lossless or lossy, indicating the preser- vation or loss of information in the process of compression or encoding. An image is divided into M 4 x 4 non-overlapping blocks. For each 4 x 4 block, the mean and standard deviation of the pixels are calculated and stored.