id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
1470	Possible mismatch spec/VTM CC-ALF	sdchi		"I believe there is mismatch between the spec and VTM regarding the CC ALF. The best match I could find for statement 1506 in the spec:
{{{
sum = ( SubHeightC == 1 && ( y == CtbSizeY − 3 | | y == CtbSizeY − 4 ) ) ? curr : curr + scaledSum (1506)
}}}

is at AdaptiveLoopFilter.cpp:1340 in VTM:
{{{
int pos = ((startHeight + i + ii) << scaleY) & (vbCTUHeight - 1);
if (scaleY == 0 && (pos == vbPos || pos == vbPos + 1))
{
  continue;
}
}}}

I assume that {{{y}}} is actually {{{yL}}}, and this is a typo. But even with this the {{{SubHeightC}}} and {{{scaleY}}} do not match. In the spec it is skipped for 420, but in the software for 422/444. The spec behavior would make more sense for me. 

As a side note, the {{{y == CtbSizeY − 3}}} is a bit redundant as this does not occur with {{{SubHeightC == 1}}}. 
"	defect	closed	major		VTM	VTM-12.0	invalid	cc alf	ksuehring XiangLi fbossen jvet@…