Chroma is getting swapped?? Please help

[dokworm]

I have some 3D videos that are field sequential.
i.e. the left eye view is on one field and the right eye view is on the other.

However, it would appear that each field has the others chroma!?!

Is there a filter to 'swap chroma' that I could use with virtualdub to reverse this problem.

The problem is easily visible when you view the fields into 2 images - you can see clearly that the chroma for each field actually belongs to the other one...

[Mug Funky]

sounds like a YV12 problem to me.

what codec?
what settings? (colour space, etc)
what decoder/player is being used? (ffdshow, virtualdub, directshow, etc)

if it's simply chroma channels being swapped, then either using a different decoder (without that bug), or running it through avisynth with "swapuv()" in it will fix it.

if it's a problem of YV12 sampling (i suspect it may be), then make the decoder output in yuy2, and be sure it's interlace aware (easy way with avisynth is to put "converttoyuy2(interlaced=true)" in there.

[dokworm]

I'll have a go at the swapuv() , I haven't used avisynth.
The 3D videos are already on DVD, you can see the chroma problem when loading them into Virtualdub and doing a 'viewfields'.

Thanks

[dokworm]

That works OK, is there any way to do it in virtualdub?

[Wilbert]

However, it would appear that each field has the others chroma!?!
I'll have a go at the swapuv() , I haven't used avisynth. That works OK (...)
If the chroma of the field 1 belongs to field 2 (and vice versa), swapuv won't solve that (it will only swap the u and v channels of each field). Perhaps you can post a short clip?

[dokworm]

I could easily post a clip or an image, what format /size etc would be most appropriate?

[scharfis_brain]

the original-format without changes, recompression or decompression.