A Review Paper on Image Compression Unit Using DCT

The field of image and video compression has gone through rapid growth during the past thirty years, leading to various coding standards. The main goal of continuous efforts on image/video coding standardization is to achieve low bit rate for data storage and transmission, while maintaining acceptable distortion.In present every multimedia device is based on battery operated system. As we know power consumption is crucial part for those device. So there is need of fast and efficient algorithm and hardware unit for those multimedia devices.as we already know compression unit is the most important part for any multimedia device. So, in this paper, various developmental stages of image and video compression standards are reviewed, including JPEG and JPEG 2000 image standards, MPEG-1, MPEG-2, MPEG-4, H.261, H.263, H.264/MPEG-4 AVC, and the latest international video standard HEVC as well as Chinese video coding standard AVS.here we also did the complete comparative discussion between different compression unit in term of time complexity and quality