Opened 6 weeks ago

Last modified 6 weeks ago

#519 new defect

MIsmatch with vtm on cu chroma qp offset enabling

Reported by: forayr Owned by:
Priority: minor Milestone:
Component: spec Version:
Keywords: Cc: ksuehring, XiangLi, fbossen, jvet@…

Description

The specification decides to enable cu_chroma_qp_offset tools only at the PPS level, whereas VTM checks also a flag at the slice level (after 'slice_joint_cbcr_qp_offset').
Is this a VTM issue ?

Attachments (1)

JVET-O2001-vE-patch-519.docx (18.4 KB) - added by delagrangep 5 weeks ago.
Suggested changes to JVET-O2001-vE

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Change history (3)

comment:1 Changed 6 weeks ago by delagrangep

Thanks for raising the issue.

This code is inherited from HEVC, and this is rather a spec issue: we make use of "cu_chroma_qp_offset_enabled_flag" which is undefined in VVC Draft.

Actually in JVET-O1168 we forgot to port the slice-level flag from HEVC, just before "if( deblocking_filter_override_enabled_flag )":

if( chroma_qp_offset_list_enabled_flag )

cu_chroma_qp_offset_enabled_flag u(1)

I apologize for having missed it.

We may discuss this issue at the next meeting, however the meeting notes seem to suggest alignment with HEVC in the discussion of JVET-O0737: "Hypothetically, we could just basically do what is in HEVC (“variant 0”)", that "variant 0" being what was adopted as JVET-O1168.

I can provide the spec fix if everyone is ok.

comment:2 Changed 6 weeks ago by forayr

  • Component changed from VTM to spec
  • Milestone VTM-6.2 deleted
  • Summary changed from MIsmatch with spec on cu chroma qp offset enabling to MIsmatch with vtm on cu chroma qp offset enabling

Changed 5 weeks ago by delagrangep

Suggested changes to JVET-O2001-vE

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