For those movies hard to compress

[woodysteven]

After compressibility testing, the movie 'The Big Blue' reported a
very high bits/(pixel*fram) value, 0.63! So, even throught a higher
bitrate like 956kbits/s can only got 59% load for 512@ resolution. In the case, however, I see the calculated bits/(pixel*frame) is 0.375 which should be considered as very high.

So, what value I should relay on? 0.375 bits or 59% load ?

-
steven
steven@steven4u.net

[diji1]

hi woody - welcome to doom9. :)

I always rely on the percentage given by gknot to choose resolution. the bits/(pixels*frames) i only use as a guide for choosing resolution on the first compression check. 59% at 512 res will give you good quality for the majority of cases imo ( ... and the guides ;) ).

if u didn't know: u can increase compressability by applying filters or using a different resize filter also, though i personally find that neutral bicubic is the lowest i like to go. as always, you should find what suits you and balance that against the quality of ur encode. have fun.

[woodysteven]

Thank you. Now I got the ideal.

Still get another question, maybe I shouldn't post here ;-)
Why the movie got a such high bits/(pixel*frame) values while others normally got about 0.4 ? Does this means that I'v got a very good DVD?

[diji1]

dividee : " ... you should disregard b/(p*f) once you have the compression test (but maybe not completely: for very difficult sources, you sometimes needs more than 70% in the compress test, and you can recognize difficult sources when you have a very high b/(p*f) and a low % in the compress test. "

maybe that answers ... :)

i think you should always trust your eyes and be ready to redo something if it's not "good" ... in your case maybe compare 480 res ( at higher compression test percentages, obviously ) with your 512 res mpeg4 video and see which is better. theres really no hard and fast rules - occasionally movies just have to be converted using out-of-the-norm settings to look right to me.

[woodysteven]

It's about 10hrs the encoding has completed. The result quality is good., 2x700M for the 160min video with 192kbits VBR mp3.

Thanks for your help!