De-interlacing 50i to 50p producing colour problems

[Stevie_McC]

Hi,

I'm remastering an old DV film but have hit a problem. I took my original 576-50i footage and ran it through StaxRip using the QTGMC field filter set at a high quality. It gave me really nice 576-50p footage which generally looks great. However, it seems the colour information isn't in sync with the luminance information. It's only noticeable on fast-moving scenes. Here's an example showing the effect...


[Attachment 63636 - Click to enlarge]

I looked at the separate fields and the colour information seems all intact and perfectly in sync on the odd and even fields. So what is happening? Is it possible the colour information is effectively running at 25fps and the luminance at 50fps?

Does anyone have any advice to fix this issue?

Thanks!

Steve.

[poisondeathray]

I looked at the separate fields and the colour information seems all intact and perfectly in sync on the odd and even fields. So what is happening? Is it possible the colour information is effectively running at 25fps and the luminance at 50fps?
.

Not if your statement is correct

If you view separated fields - that's 50 fields per second. You should be able to see the defect on separated fields if the color was misaligned or running at different rate

There might have been a color resampling operation done in a progressive manner, while still interlaced; or the source filter might be returning different pixel type than it should be - PAL DV should be 4:2:0

Post the log file and sample of the source

[jagabo]

Probably a ConvertToYV12() without specifying interlaced, ie ConvertToYV12(interlaced=true).