SeparateFields & color format

[mathmax]

Hello

I have a few questions regarding the following code:

Mpeg2Source("interlaced.d2v") #original video is YV12 interlaced
SomeSmartBob()
Somfitlers()

SeparateFields()
Selectevery(4,0,3)
weave()

1. After SomeSmartBob() is applied, is the color format automatically changed to YV12 progressive (for example when using QTGMC, bob(), yadif(), etc.)?

2. If the color format is YV12 progressive, then one line over 2 doesn't have chroma informations. So I guess SeparateFields() will first convert to YV12 interlaced, else half of the resulting fields will not hold any chroma information. Could you confirm this assumption?

Thank you in advance.

[TheSkiller]

1. Sort of yes and sort of no. It might sound odd at first but technically there is no "interlaced" or "progressive" YV12. It's all just YV12 and whether it needs to be treated interlaced or progressive depends on the presence of actual interlacing, both for downsampling to and upsampling from YV12.

2. SeparateFields just takes the chroma that belongs to the corresponding lines, and every chroma line is shared by two luma lines. Since the chroma is shared there are no monochrome lines.