Minimizing those Pesky little Compression Artifacts

vbimport

#1

HI All;

I’ve been backing up my DVDs to my PCH & NAS, … and have been using DVDFab using Generic, … using generic.avo.xvid.audiocopy , and per Gregiboys recommendation I’ve been keeping the Bitrate slider between 1100 - 1500. On some avis though, … I still see those compression blocks in the shadow areas, etc … on the TV. (these avi files are 1.5g or thereabouts in size)

My question is, … if I had done the avi at say 1300 bitrate, what whould improve the quality the most if I were to re-convert the DVD? … going up on the bitrate to either 1500 or 1700, … or selecting 2 pass instead of 1 pass?

Another question, … I’ve seen other avi files of DVDs, that are only 700M in file size, … yet I don’t see as many blocky artifacts as I do using my process, and my files are twice as big. Are these other guys using a different program? (is it possible to tell what codec, settings are used on these avi’s?)

If I had the Hard Drive space, I would just backup the videos w/o compression, … but I don’t have the luxury for that yet.

thanks for any help, or links that might help me figure this out.

ONe last question, … I’ve noticed that DVDFab seems to pick a particular bitrate when you go to the Configure screen. Is there any significance to this number?
On a particular DVD, Polar Express …
avi.h264.audiocopy shows 768 bitrate and 873M file size
avi.h264.mp3 shows 900 bitrate and 691M Fiile Size
avi.xvid.audiocopy shows 999 bitrate and 1037M file size

Would using h264.audiocopy and upping the bitrate to 1300 be better than using xvid and upping the bitrate to 1300?

Sorry if these questions are NEWB in nature, … as I’m trying to learn.

thanks
Allen


#2

i dont know about the settings but use GSPOT for codec information.
http://www.headbands.com/gspot/


#3

Both increasing the bitrate and 2 pass will increase the quality.

Increasing the bitrate will increase the filesize.

I understand that the bitrate calculated by Fab is what it thinks is best, but I still use my own settings.

As I said, it is a bit of trial and error to find out what works best for you…

Try a test of the H264 and AVI at the same bitrate. Just do one chapter and compare.


#4

The “bits/pixel” value is a more universal indication (it is recalculated as you change screen sizes or bitrates). Try to keep it above 0.15 or so. I do my conversions at 0.4 or more, but not all mobile devices support the bitrates necessary to achieve those values with large screen sizes.


#5

The way I generally work is:-

  1. Find the optimal screen size for device that you want to play on.
  2. Find the optimal audio setting for the device.
  3. Once I have these worked out, I then try the video rate settings.

Once I have it all figured out, I then modify a profile so that these settings are the defaults.

Sigs is correct but I just find it easier to work this way.