Hi, i am a newbie and have been reading in the forums that you can save 20% bitrate with certain dvd's (eg. by ticking forced film in dvd2avi on a NTSC FILM DVD to remove the RFF/TFF flags and then replacing the flags while encoding at the 23.976 framerate). At present i am trying to improve the quality of a dvd i am ripping and wondered whether i could achieve this 20% bitrate saving and thereby increase the quality.

First i opened DVD2AVI and pressed F5 with forced film unticked and found out that the DVD was a %Film and a %NTSC (never lower than 75% Film and averaging 85% film) oh and it said progressive. As i understand you should only tick forced film if the % is 95 or over so i left it unticked and saved project. I then took it to virtual dub and encoded a three minute clip with DIVX 5.

Next i went back and did the same process but with FORCE FILM ticked in DVD2AVI, creating the same exact 3 minute clip in virtual dub with DIVX 5.(same compression bitrate was used).

I found the following: FORCE FILM unticked 17,308kB
FORCE FILM Ticked 15,776kB
% SAVED 8.85% (17,308-15,776)/17,308

I have two main questions:

1) Why am i not achieving a 20% saving? (what am i doing wrong?)

2) When enabling FORCE FILM and therefore disabling the flags, Why does the 3 minute clip i encoded play fine on my computer and on the TV via my computer? (I thought you had to put the flags back in when encoding which i did not ?

I am really confused and would like to achieve the full 20% saving if any one could help that would be great.