Change field order

[peho]

I have a lot of DV-AVI-files that are tff and what I understand DV ia by default bff.

I've tried avisynth together with virdub and avs2avi w direct stream copy/no recompression, but I just wan't to change field order.

Is it possible to change field order in a dv-avi without recomression?

/Peter

[Si]

Unfortunately no.
regards
Simon

[peho]

Does anyone have any idea how I got all my dv-avi tff?

I used iuVCR recording from my hi8-cam with PCTV rave card and ms directshow dv codec.

Thanks

[Si]

I never had expereience of doing this but I imagine its down to the difference between capturing using a DV Device (a camcorder) which always should capture BFF (cause that's the spec) and capturing using an analogue card (which normally capture TFF IME) and then compressing it using a codec (which just happens to be a DV one)

A codec wouldn't normally change the field order (unless there was an option in its settings) - I know none of the codecs I use do.

Is the captured field order actually causing you a problem because there may be ways around them?

In future, you could maybe try using Donald Graft's Reverse Field Dominance filter at capture - your system and the filter are maybe fast enough to do it in real time.

regards
Simon

[Guest]

Can you post a small unprocessed sample clip? Maybe it's field swapped.

[communist]

Is the captured field order actually causing you a problem because there may be ways around them?
It most certainly is. Just encode a TFF clip to DV with VirtualDub and play it.. *jerk jerk jerk*.

Thats because every DV decoder is expecting BFF (which is the standard for DV).

@peho if you really have to use DV codec for capturing (not really recommended) make sure you either feed it with a BFF source or postprocess it Avisynth.

[Si]

@communist
If the peho is playing the files through a proper interlaced TV-out card then he'd have a problem but I wouldn't think it would make any difference if he's just viewing it on a computer.

regards
Simon

[scharfis_brain]

he said he digitised his video through an analogue capture card using the dv-codec.

this constellation is likely to produce tff dv-files, because analogue capture cardis commonly put out TFF.

[peho]

Is the captured field order actually causing you a problem because there may be ways around them?
Yes, it's a problem, if I would like to use my standard work order for DV.
From my DV cam I capture DV with Scenalyzer, splitting it to clips with date/time filenames and at last produce a DVD with Pinnacle Studio 9.
Scenalyzer works really great also for splitting analogue video with optical scene detection, renaming clips and saving it all with batch processing. I really like to use it also for my analogue capture.

My problem is Studio (always something:(), it can't change field order.

In future, you could maybe try using Donald Graft's Reverse Field Dominance filter at capture
Good though, I didn't think of that one.
I'll try it later tonight and also the built in one in iuVCR.

Maybe it's field swapped.
Yes it is. I've checked it with separatefields in AVIsynth.

DV codec for capturing (not really recommended)
Why do you not recommend DV codec? Do you think I loose a lot of quality?

[Guest]

Yes it is. I've checked it with separatefields in AVIsynth. Then you want to use SwapFields().

Are you aware of the important distinction between changing field dominance and swapping fields? They are not the same thing.

[peho]

I must say that I'm not sure.
What I can say is that if I use swapfields().separatefields() movie is jerky and with assumetff().separatefields() it's smooth.
/peho

[Guest]

That's why I asked you to post a small sample.

[peho]

Thanks, neuron2.
I've been reading some more now and know the difference.
I will go on try to change dominance on-the-fly in iuVCR.
/peho