Dude don't comment if you don't know and misguide someone with a reference which is totally false.
There are some good books (some valid source in internet as well) available in market about on video compression like MPEG 2 and MPEG 4. So first go and study those. For an example - Telecommunications Essentials, Second Edition: By Lillian Goleniewski, Kitty Wilson Jarrett is a good book.
VIDEO QUALITY depends on bitrate not on compression ration. Mpeg4 H.264 produce same quality of MPEG 2 at half the bitrare or less used by MPEG 2. MPEG 4 is object based compression whereas MPEG 2 is frame based compression.
@ Dr.Vijay Peketi No benifite to consumer end but it definitely benefit to service provider end such as (TATASKY) which enable them to beam more number of channels with the same bandwidth used by MPEG 2. Which means you can expect double the number of channels(almost 400+ channels from 230 till now) on TATASKy if they convert to the MPEG 4.
Can you refer the relevant para from the book you cited instead of writing vaguely.