Opened 5 years ago

Closed 5 years ago

Last modified 5 years ago

#238 closed defect (wontfix)

N0473 – Deblocking of Internal Transform Boundaries

Reported by: bheng Owned by:
Priority: minor Milestone:
Component: VTM Version: VTM-4.2
Keywords: Cc: ksuehring, XiangLi, fbossen, jvet@…

Description (last modified by ksuehring)

The following code will cause the deblocking process to stop if a CU is not aligned with the 8x8 filtering grid. However, internal transform boundaries can still fall on the 8x8 filtering grid even if the CU does not. So, I believe the following lines should be deleted.

void LoopFilter::xDeblockCU( CodingUnit& cu, const DeblockEdgeDir edgeDir )

  if (edgeDir == EDGE_HOR)
    if (!((cu.block(COMPONENT_Y).y % 8) == 0))
    if (!((cu.block(COMPONENT_Y).x % 8) == 0))


Change history (5)

comment:1 Changed 5 years ago by ksuehring

  • Description modified (diff)

comment:2 Changed 5 years ago by AnandMeher

Dear Brian, Experts,

My understanding is that the current design of deblocking filter still does not filter any of the "sub-pu" edges and "sub-tu" edges if the corresponding CU edge does not align with the 8 x 8 sample grid.
I believe that some of the CE tests under CE5-2 category also address this problem.

Thank You

Best Regards
Anand Meher Kotra

comment:3 Changed 5 years ago by Kenneth

Dear Anand, Brian, Experts,

Anand is correct that there is a CE on deblocking on 4x4 grid that takes care of this issue and also takes care of deblocking of corresponding CU boundaries on 4x4 grid. I suggest we wait with considering this until next meeting. We then also hopefully knows if we decide to go for 4x4 grid deblocking.

Best regards

comment:4 Changed 5 years ago by bheng

  • Resolution set to wontfix
  • Status changed from new to closed

comment:5 Changed 5 years ago by kiranmisra

It would be nice if there is a test in the CE where deblocking does not skip CU's not on the 8x8 luma grid

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