what is field order?

[radkid]

Hey,

I was wondering if anyone has a second to point me to some reading material on field order... Or maybe some wise person could post some information about this topic.

I am confused as to what field order actually is. E.g. I encoded an analog captured avi (huffy) to mpeg2 (using aviscript and CCE) and it was a bit jearky when i made the final dvd movie and tested it on my standalone player. So sombody suggested i use RESTREAM to change the field order to TOP FIELD... i just did this an i am acutally compiling my project again to test the new movie. Thing is i have no idea what selecting top field acually does and why this would sovle the jearky video problem. Any info is appreciated.

Also maybe somebody has another idea why my movie is jearky when the screen pans across scenes...

TIA

[andkiich]

If I don't get this right, I'm sure someone will correct me. Also, I'm pretty sure that this is more complicated than the way I'm going to explain it, but I'm going for layman's terms and not to technical.

Interlaced video essentially has 2 images that make up a frame, an A and a B. A has half the image, B the other half, when they are both merged together, they form the completed frame. If one is displayed before the other, the images will look jittery or shake.

[Marco33]

This is from the Glossary but, it's pretty much what andkiich said.

Field
In an interlaced video a field is 1/2 of a complete picture (Frame) consisting of the even or odd scanlines in the frame. Usually each field is labeled ie. Field A and Field B. When working with interlaced video it is important to note the Field Order (if Field A comes before Field B in the video stream) especially when encoding. If you notice flicker after encoding you will want to change the field order in the encoding template and reencode.

[Nelson37]

The visual effect this causes should be very pronounced in any motion scene, as the fields are displaying out of time sequence. Do a stop motion view to confirm this, you will see a forward - back - forward, or sometimes forward - freeze - forward, progression.

I am suggesting this as your description of "a bit jerky" seems like it could be something else. Would also suggest a short test re-encode as I have had problems with ReStream, also since it won't be your standard procedure it may not give standard results.

If the field order reversal doesn't solve it, post your AviSynth script and cap settings, etc.

[radkid]

hey,
thanks for the replies...

Do you guys know how to control the interlace when encoding from huffy avi to mpeg 2 using avi script and cinema craft encoder? Can you do it with TMPGEnc... i could always start to use that if i will get good results?

i am getting jearky video when the movie pans in certain scenes.


TIA

[Marco33]

I use AVS scripts with CCE. When I do a capture I never touch any interlaced settings. CCE 2.5 I belive is always Interlaced but has a setting for Progressive but I don't touch it when converting captures.

If it jurks when the picture pans... that sounds like field order to me. I would do a 5 minute test ( 2 seperate captures) with upper field checked & unchecked in CCE and see how that goes.

CCE is kinda backwards when it comes to field order.

[radkid]

Hey,

I am using:

CCE version 2.67.00.11
AviSynth version 2.5
AviScript 2.0 Trial

Sorry, dont see an option for field order in any of the menus/settings.

Could you describe where this is?

What versions of these programs are you using?

TIA

[Marco33]

2.5

In my version I double click the file in the main CCE window, that will bring up a new window, in there is "Other settings"= Video, click that. There's a check box called "Upper field first"

It may not be the same in your version.

[radkid]

If i used TMPGEnc will i get similar results as CCE ?
[ i just checked and TMPGEnc deffinitely has a field order option ]


( i hear the main difference is simply encoding time is that true? )

[Marco33]

I've never used TMPGEnc to re-encode but from what I've read here... Yes, It works just as good as CCE. It will run longer.

There HAS to be a field order somewhere in CCE version 2.67.00.11.

[radkid]

Maybe...
I just dont know where.... bah.

However i tried to encode with TMPGenc plus the latest version and my dvd movie is really smooth, much better than when i used CCE. If i ever find the field order option in CCE i am sure it will look as goood as the tmpgenc encode. Ah well, if it works it works!

now all i gotta do is apply some filters with virtual dub to smooth the video out and then encode with tmpgenc again to get better results i hope!


Marco33, do you use the filters in aviscript? or do you use another utility like virtual dub ?

[Marco33]

I just use the letterbox filter.

I use the anti noise in CCE. Since I use a DV converter the tapes I convert have to be in good condition to begin with so, I don't have a problem with poor picture.


How about a new topic.

Where is field order setting in CCE 2.6?


It's a shame to spend that money and not be able to use it.

[kalo]

Hey !

some info from me (author of AviScript), hoping can help:


The field order in CCE (version 2.66 and lower) is called: Upper field first [Section Video]
The field order in CCE (since version 2.67) is called: Offset Line [Section Video] !!

set
Offset Line to 0 !
that's the same as Deselect Upper field first.


One Tip to Interlace:

To deinterlace a interlaced video (most after TV capture) use one of the Deinterlace filter in AviScript. But: If you want to play on television instead of a computer monitor, so don't change the original and don't deinterlace the video to get the best results !.
In CCE: If you encode an interlaced video, so deselect the option [Progressive frame] flag. Important: if your DVD standalone player produces a jearky video, so click in CCE to the button [Video...] to get the Encode Setting Window, deselect [Upper field first] (CCE 2.66 or lower) or change [Offset line to 0] (CCE 2.67).

=> hoping this can help you. I had the same problems before (jearky videos), now I don't deinterlace the videos in AviScript, set Offset Line to 0 and get a very good quality on my DVD standalone player / television.

=> test the Time Smoother Filter in AviScript to denoise the video (it's my favorite)
two links for more infos:

CCE:
http://forum.doom9.org/showthread.php?s=d004e3ea40a5a27bb11b1030f9920306&threadid=53770

AviScript (interlace):
http://www.aviscript.de/howto/HowToDVD.htm


best regards
Kai Locher