Opened 5 years ago

Closed 5 years ago

#165 closed defect (fixed)

Mismatch between Spec and software

Reported by: adarsh Owned by:
Priority: minor Milestone:
Component: spec Version: VVC D5 v5
Keywords: Cc: ksuehring, bbross, XiangLi, fbossen, jvet@…

Description

CCLM checks luma reference samples only at the top and left of the current block; this was part of the software from the beginning; it did not check the top-left reference samples. The Spec currently seems to incorrectly refer to the top-left luma reference samples.

The related text Section 8.3.4.2.8 may be referred to using the tag "availTL."

Change history (10)

comment:1 Changed 5 years ago by bbross

  • Version set to VVC D4 v2

comment:2 Changed 5 years ago by bbross

  • Version changed from VVC D4 v2 to VVC D4 v3

comment:3 Changed 5 years ago by bbross

  • Version changed from VVC D4 v3 to VVC D4 v4

comment:4 Changed 5 years ago by bbross

  • Version changed from VVC D4 v4 to VVC D4 v6

comment:5 Changed 5 years ago by bbross

  • Version changed from VVC D4 v6 to VVC D4 v7

comment:6 Changed 5 years ago by bbross

  • Version changed from VVC D4 v7 to VVC D5 v4

comment:7 Changed 5 years ago by bbross

  • Version changed from VVC D5 v4 to VVC D5 v5

comment:8 Changed 5 years ago by bbross

  • Component changed from spec to VTM
  • Version changed from VVC D5 v5 to VTM-5.0

This check is actually needed and thats why I added it.
For the TL sample it is not sufficient to check L and T because with slices (formerly known as tile groups), the case can happen where TL is n.a. but T and L are available or vice versa.
See Figure 6-4 in the current draft where the first CTU in the 6th tile in raster-scan has T and L available but TL is n.a.
Hence, this condition should be added to VTM to cover these cases.

comment:9 Changed 5 years ago by bbross

  • Component changed from VTM to spec
  • Version changed from VTM-5.0 to VVC D5 v5

After with Discussion with Karsten, I understand that tiles also inside a slice are independent.
Thus, TL is always n.a. when either L or T is n.a. and as long as we do nat have dependent tiles, the TL available check can be removed from the spec.

comment:10 Changed 5 years ago by bbross

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

Fixed in D5 v6

Note: See TracTickets for help on using tickets.