vob aspect ratio problems

[cybmole]

I am gettign poor results from VOB to DIVX ( file to mobile) using VOB previously made via DVD VOB passthrough.

DVDfab does not seem to get proper aspect ratio from vob file so the divx output files are distorted

e.g.
all vob are reported by gspot as 720 x 480.

test 1. 3 x 4:3 aspect files, from same source DVD . fab wants to output them as 416x480 ! impossible to set a correct option. ( maybe fooled by a lot of black in opening frames ??? )

test 2. 4:3 again, 3 vob files from another source dvd. fab offers 720 x512 but not 720 x 480 , and it defaults to something lower. I think I get that a .Avi will have one different dimension because it will use square pixels, whereas a VOB file, like a DVD, will have 720 x480 but wil also include info on how pixels shouel be stretched to form 4:3 , 16: 9 etc as needed. is that correct ?. IF so should I just match on the 720 wide value for best results and let fab choose the other dimension ?

test3 16 : 9 dvd source & 16: VOB from that source

vob analysis ( gspot) 720 x 576 16 : 9 sar 1.25 par 1.422 dar 1.778

vob to avi convert at default settings.
looks awful

avi output analysis (gspot) 720 x 512 both 16 : 9 and 4:3 are now greyed out.
sar 1.406 par 1.0 dar 1.406

this vob was made from source dvd using an older version of dvdfab

[signals]

Hi cybmole
You will generally get better results if you make the MPEG-4 conversion from the original DVD or a decrypted folder that is still in DVD-Video format (using DVD to Mobile). I think some of the information used to set the output size is in the IFO files, which are gone after VOB Passthrough. All DVDs are 720x480, but this is not necessarily the active video, which may have been letterboxed widescreen, anamorphic transfer, etc.

[cybmole]

Hi cybmole
> You will generally get better results if you make the MPEG-4 conversion from the original DVD or a decrypted folder that is still in DVD-Video format (using DVD to Mobile).

that seems to be the case, yes. Unfortunately I have 3 VOB files for which I gave away or lost the original DVD. I can redo everything else from source though.

> I think some of the information used to set the output size is in the IFO files, which are gone after VOB Passthrough.

i think not because divx converter from divx.com works with the same test w vob files as input & gets its output aspects right. ( its output does not play nice with VLC player though - there's an annoying "audio starving" glitch on occassion that I am discussing on VLC forum).

> All DVDs are 720x480,

yes - exepct pal with seems to be 720 x 576

> but this is not necessarily the active video, which may have been letterboxed widescreen, anamorphic transfer, etc.

yes - hence the need for a smart converter like dvdfab that can remove black borders - the imtoo/xilisoft product fails on this.

[Complication]

VOB Passthrough cannot remove the black boarders because it does not modify the video stream and the black boarders are part of the MPEG2 encoding. There are also some DVDs that have done a poor job of identifying the video aspect ratio correctly in all parts of the DVD (IFO, VOB header, VOB stream). This is not a problem when played as a DVD because the players figure it out (or you press a little button and they play it differently).

Signals is right. It is best to rip to the hard drive and then do your conversion from there. If you use Main Movie mode then the space used will be only slightly larger than VOB Passthrough. Unfortunately, DVDFab does not offer (that I'm aware of) an option to not split the ripped VOB files (like the old DVD Shrink) which would one large file with the DVD stile wrapper and features.

[GregiBoy]

As the guys have said, you are doing this the wrong way. Use DVD to Mobile and have a read of the "Best Practice: DVD to Mobile" thread in the Knowledgebase are of the forum.