Please Help with Compressor bit rate formulation....

Question

This is my first time with Compressor 2.
I am used to working with Compressor1.
After I compressed a couple of sequences and brought them into DVD SP4.
My disk meter read 6.1 gb.
I compressed a total of 2hours and 11minutes at 4.2 mbps.
Using AC3 for my audio.
According to my calculations that should of worked.
Does anyone have any comments or suggestions?
Did they add something to the new compressor that I should have set?
Thanks,
-marco

Answer 1

hey marco, what are you using as your calculations?
usually what i do is a get multiply the audio in seconds by the bit-rate of the audio i am using (0.192 .ac3 stereo).
then i take that sum and subtract it from the product of the disc size minus 5% of head room (dvd-r = 37600 Mbits)
finally i take that remainder and divide that by the product seconds of the movie.
that gives me the average bit-rate.
for my max i just add 2 to the number!
so in your case:
131 x 60 x 0.192 = 1510 Mbits
then:
1510 - (37600 x 0.05) = 34210 Mbits left for video
finally:
34210 / (131 x 60) = 4.35 Mbps for average and:
4.35 + 2 = 6.35 Mbps max
shoot we kinda got the same numbers. so what settings are you using?
is your audio stereo or surround sound?
are you using a 2 pass vbr?
some more inside on your settings please