Opened 10 years ago

Closed 9 years ago

#341 closed defect (fixed)

Clipping value for scaled motion vector predictor is not appropriate

Reported by: ToshiyasuSugio Owned by: bbross
Priority: minor Milestone: D7
Component: Text Version: D6 (H1003) dI/dJ/dK
Keywords: Cc: bbross, wjhan, jct-vc@…

Description

In JCTVC-H1003_dK, motion vector is treated as an integer value even though it sometimes shows half or quarter pel position.
However, a scaled motion vector is treated as a floating value in expression (8-138), (8-146) and (8-156).
It should be modified to integer value such as below.
And, there is one typo in expression (8-146) (mvLXA should be replaced with mvLXB).


expression (8-138)

original

mvLXA = Clip3( -8192, 8191.75, Sign( DistScaleFactor * mvLXA ) *
( (Abs( DistScaleFactor * mvLXA ) + 127 ) >> 8 ) ) (8-138)

modified

mvLXA = Clip3( -32768, 32767, Sign( DistScaleFactor * mvLXA ) *
( (Abs( DistScaleFactor * mvLXA ) + 127 ) >> 8 ) ) (8-138)

expression (8-146)

original

mvLXB =Clip3( -8192, 8191.75, Sign( DistScaleFactor * mvLXA ) *
( (Abs( DistScaleFactor * mvLXA ) + 127 ) >> 8 ) ) (8-146)

modified

mvLXB =Clip3( -32768, 32767, Sign( DistScaleFactor * mvLXB ) *
( (Abs( DistScaleFactor * mvLXB ) + 127 ) >> 8 ) ) (8-146)

expression (8-156)

original

mvLXCol = Clip3( -8192, 8191.75, Sign( DistScaleFactor * mvCol ) *
( (Abs( DistScaleFactor * mvCol ) + 127 ) >> 8 ) ) (8-156)

modified

mvLXCol = Clip3( -32768, 32767, Sign( DistScaleFactor * mvCol ) *
( (Abs( DistScaleFactor * mvCol ) + 127 ) >> 8 ) ) (8-156)


Change History (3)

comment:1 Changed 10 years ago by DefaultCC Plugin

  • Cc bbross wjhan jct-vc@… added

comment:2 Changed 9 years ago by bbross

  • Milestone set to D7

comment:3 Changed 9 years ago by bbross

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

Fixed in JCTVC-I1003_d6.

Note: See TracTickets for help on using tickets.

This list contains all users that will be notified about changes made to this ticket.

These roles will be notified: Reporter, Owner, Subscriber, Participant

  • Benjamin Bross(Owner, Subscriber, Participant)
  • jct-vc@…(Subscriber)
  • karl.sharman@…(Always)
  • Karsten Suehring(Always)
  • Toshiyasu Sugio(Reporter)
  • Woo-Jin Han(Subscriber)