3 hr. dvd vs. 3.25 hr. dvd backup

vbimport

#1

I recently backed up a couple of dvd’s to dvdr and noticed a HUGE encoding speed ( 3.X realtime vs. 1.6 realtime ) difference between a 3 hour movie and a 3 hour and 20 minute movie.

The only reason I can come up with is that at some level the rate of compression causes cce sp to have to work really hard to achieve an adequate level of quality.

Does anyone know specifically what that level is?

I am know looking for a 3 hour and 10 minute dvd to test with.


#2

I think it has probabally got more to do with the movie content rather than the time. DVD’s use GOP (Group Of Pictures) structures and key frames to make a picture.
Key frames have the total picture and are them followed not by more pictures, but rather a discription of what has changed to make the next frame.
In movies where the is a lot of movement, there are more key frames and the discriptions are bigger so the movie can still looks fluid.
If CCE gets a movie that has little movement, then it will be easier for it to transcode into another format (just like we find it easier to read a newspaper article than the smallprint on an insurance policy, it just takes less brainpower to comprehend it).


#3

Interesting point.

The two movies I speak of are lotr:tt(2:58) and lotr:rtotk(3:20).

I think there was a lot more movement in the third installment if I remember correctly + the extra compression I guess.