I have made some text based CG in 3D Max to an uncompressed 640 x 480 avi file. To convert to MPEG 1, I must have tried to use all possible options in TMPG encoder but quality of CG is bad compared to what i see using professional hardware encoders. I see blocky and smudgy effect around the text area.
I even tried bit rate of 4000 and CQ bit rate.

All my captured video look cool unlike my CG. Even a text super overlay on captured live video show smudgy dirt around the text area.

Can anyone help?