Randomly changing field order - my solution

[Christian]

To whom it may concern.
Due to my searches concernig "field order" i have found several Threads asking questions in this direction, so i'd like to share my findings.

I had a problem with randomly changing field order in my captures. It seemed to happen on bad as well as on good sources.
After excluding several possible error sources like VDub and the MJPEG-Codec i switched the drivers for my WIN-TV from original VFW ones to the BTWincap-Driver.
These drivers have solved my problem.

BTW: I have found no tool to correct randomly changing field-orders, haven't I searched hard enough ?

Info:
I am capturing with VDub into MJPEG with full resolution PAL with a WIN-TV PCI-card with the latest VFW-Drivers (now BTWinCap). Most of my Captures must have been Deinterlaced because if not they sometimes where OK and after a scene change they where shaky.

Greets
Christian

[Zhnujm]

Originally posted by Christian
BTW: I have found no tool to correct randomly changing field-orders, haven't I searched hard enough ?


the telecide filter should solve such problems. available for virtualdub and avisynth.
but anyway, its very slow so your solution for the problem is far better :)

[^^-+I4004+-^^]

Originally posted by Zhnujm
the telecide filter should solve such problems. available for virtualdub and avisynth.


and what if it's the video source?
telecide is not changing field order anyhow,but just
recovering progressive film frames...
random field order problems mean back-forth jerk from time
to time.....no way to correct those...(not that i know of)

anyhow,im using vfw bt ref. drivers on win98
and btwincap on w2k,and never seen that problem;
i HAVE seen PAL phase shift on film source,but that's the problem
of the source itself,and not capture devices's
thing (i have tested this;same phase shifts are
present when i capture directly from tv and with the VHS
capture of same video ie. it's in the video signal itself
and card is capturing it every time in same way...)
this problem is easy to solve with telecide()

,but i thought the guy was talking about general
field order problem...like in all the capturings,and not just
PAL phase shifts (fields that don't belong together are in teh same frame)on film sources.....
[edit;to be completely precise:PAL phase shift has nothing to do with
field order problems,so telecide() need not be mentioned here....]

[Christian]

the telecide filter should solve such problems.
I have tried several filters to solve the problem, e.g. DFOC, Telecide and a VDub filter called Progressive frame restorer all without success.

@^^-+I4004+-^^
Captures from the same VHS-Tape have field reversal at different time stamps so in my case it could not be the source only. My capture card seem to drop single fields instead of hole frames.

What drivers do you mean with bt ref. drivers. The drivers from the manufacturer or a driver i haven't had till now ? I would prefer a VFW driver compatible to the WinTV Software from Hauppauge. Don't get me wrong, btwincap is an excellent WDM driver but vfw gives me 10% less CPU usage which could be used for other things e.g. filters while capturing.

Greets
Christian

[^^-+I4004+-^^]

>My capture card seem to drop single fields instead of hole frames.

are you sure of this?
this,then is not "field order problem",but some fields will
get to be repeated...(same as frames get to be repeated on frame-drop problem...)
field order problems don't suffer from that...they have ALL
the fields (no repetitions) but in the wrong places in time....
have you tested suspicious video with
avs' "separatefields()"?

>What drivers do you mean with bt ref. drivers.

see the "btreference-notes.txt"
on
http://i4004.bizhosting.com/
details are there........

there are vfw drivers on "atv2000" web
http://mikecrash.wz.cz/atv2000/atv2000.htm

and also on "askey" web;
http://www.askey.com/html/support.html
["tv424.zip" seems to be the file....
select "tvcard",and seems like many models use this one
on win98]

i have compared "btpcivid.vxd" versions in all three drivers
(mine,atv2000 one,and askey driver)
and it's the same file........
(this is RSS-Brooktree 4.1.8.8 "bt video section" driver)

the VFW drivers i use were shipped with my card (on installation cd)
and they swap fields,but this is easy to recover with vdub capture
or during the post-process......not really a problem...


perhaps hauppauge and pinnacle were modifying these drivers(?)
(i know that pinnacle didn't use bt WDM driver but their own...
that's for sure,but dunno about vfw ones....you tell me what's the
version of haup. driver etc.)

[Zhnujm]

Originally posted by ^^-+I4004+-^^

i HAVE seen PAL phase shift on film source,but that's the problem
of the source itself,and not capture devices's
thing (i have tested this;same phase shifts are
present when i capture directly from tv and with the VHS
capture of same video ie. it's in the video signal itself
and card is capturing it every time in same way...)
this problem is easy to solve with telecide()


thats what i thought because i got this very often with my wintv pci card. but well, if its not card dependent hauppauge had my apology. :)

[Christian]

Hi,
I've done some research the last days, so forgive me being offline for some days.

>have you tested suspicious video with "separatefields()" ?
I've used the MJPEG open file options from VDUB to test with separated fields.

I use the card under W2K with VFW drivers so i think the versions are different to yours. It says something about Version 4.1.8.17347.

So back to my research.
I've saved an image of my working OS to DVD and made a clean new installation of W2K. After I thought i had every patch installed i couldn't get rid of massive frame-drops. So, i turned to XP and gave it a try with WDM and VFW drivers. I was unable to get the VFWWDM-wrapper to work with VDUB (or wise versa) or any other application except the WinTV from Hauppauge to work with WDM. Also those direct Show apps won't work. VFW-drivers worked with little frame drops but with my original problem of changing field-orders.

OK. Took a deep breath and switched back to the image i've made before. I took the original CD from Hauppauge with an older version (3.08) of the VFW drivers for W2K and made a JBOD out of my RAID0 Array to see if i get less frame drops and hey a little step into the right direction was done.
I captured some short scenes without frame drops and had a look at it with splitted fields. Most of them have the first 6 to 10 frames in another order than the rest.
I captured 2 hours now with 3 frames dropped and i know the first frame drop has occured after around 45 minutes and hey i got a revearsal after 47:23 !
The driver seem to check the field order and gets it wrong after frame-drops.

I think the best thing would be to contact the guys making btwincap and report them that my card isn't working in stereo. If they can solve this i could switch to there driver.

I would like to thank you for your hints and i wonder wy other people are happy with the original Hauppauge drivers (must be divx fans, cause it's progressive after compression) or with the btwincap working in mono only.

Cheers
Christian