DeBlock Half-D1

[mathmax]

Hello

I would like to deblock a PAL Half-D1 video (352*576). If I separate the fields, the blocks size are 8*8. If I bob the video, the blocks size are 8*16.

Since Deblock_QED() is designed to provide 8x8 deblocking, I think it's better to deblock on the separated fields (without bobing). But I wonder if Deblock_QED() is purely a spatial filter cause if it has any temporal processing, the scan lines should be aligned... and I should then consider to bob before applying it.

So my question : is Deblock_QED() only a spacial filter?

[Didée]

Yes, QED is purely spatial. Using it on bobbed video is generally not recommended - the mere process of bobbing usually is altering (softening) the vertical block transitions in such a way that the underlying deblock() often decides there would be nothing to do in vertical direction.

[Mounir]

deblock interlaced source:
par=getparity()
SeparateFields().PointResize(width,height)
Deblock_QED(24,28,uv=3)
AssumeFrameBased()
SeparateFields()
Merge(SelectEven(),SelectOdd())
par ? AssumeTFF() : AssumeBFF()
Weave()

credits to didée for this code

[mathmax]

Thank you for your answers.
I don't think it's needed to resize the fields in my case since the source is Half-D1 and thus the fields have the correct aspect ratio with 8*8 block size.

Why do you separate the fields two times in your script?

[manolito]

Would the following method using StickBoy's routines (from jdl-interlace.avsi) also deblock an interlaced source correctly?

Deblock Interlaced
JDL_UnFoldFieldsVertical(flip=true)
Deblock_QED(24,28,uv=3)
JDL_FoldFieldsVertical(flip=true)


Cheers
manolito

[Mounir]

use the code i have posted above manolito it's more complete

to see if it's better or not use this code at the en end of your script:
Y = GreyScale()
U = UtoY()
V = VtoY()
StackHorizontal(Y, StackVertical(U,V))

OR
Histogram(mode="luma")

[manolito]

Thanks Mounir for your suggestion.:thanks:

Whether UnfoldFieldsVertical works or not probably comes down to the question if the Deblock algo only works with 8x8 blocks, or if it also can handle 8x4 blocks. (because this is what UnfoldFieldsVertical basically does. It separates the fields and stacks them vertically thus converting 8x8 blocks into 8x4 blocks).


Cheers
manolito