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#214 closed defect (fixed)

remove transform reordering for 0.5Nx2N transform

Reported by:	xzheng	Owned by:
Priority:	major	Milestone:
Component:	HM	Version:	HM-4.0
Keywords:		Cc:	fbossen, ksuehring, davidf, jct-vc@…

Description

At HM4, when 0.5Nx2N transform is used, 0.5Nx2N input array is reodered to 2Nx0.5N array, and then 2N-pt transform is done followed by 0.5N-pt transform at encoder side. At decoder side, 0.5N-pt inv-transform is done prior to 2N-pt inv-transform when 0.5Nx2N transform is used. After transformation, 2Nx0.5N output array is reordered to 0.5Nx2N array.

To be consistent with other transform processes, transform data reordering for 0.5Nx2N transform need to be removed. The attached is the files relate to the modification.

After the removal of transform reordering, no impact on coding efficiency. The below is the results compared to HM4.

	Random Access HE
	Y	U	V
Class A	0.0%	-0.1%	-0.1%
Class B	0.0%	0.0%	0.0%
Class C	0.0%	0.0%	0.0%
Class D	0.0%	0.1%	0.0%
Class E
Overall	0.0%	0.0%	0.0%
	0.0%	0.0%	0.0%
Enc Time[%]	100%
Dec Time[%]	101%

	Random Access LC
	Y	U	V
Class A	0.0%	0.1%	0.0%
Class B	0.0%	0.0%	0.1%
Class C	0.0%	0.0%	0.0%
Class D	0.0%	-0.1%	0.0%
Class E
Overall	0.0%	0.0%	0.0%
	0.0%	0.0%	0.0%
Enc Time[%]	100%
Dec Time[%]	100%

	Low delay B HE
	Y	U	V
Class A
Class B	0.0%	-0.2%	-0.1%
Class C	0.0%	-0.1%	0.0%
Class D	0.0%	0.1%	-0.2%
Class E	-0.1%	-0.1%	0.2%
Overall	0.0%	-0.1%	0.0%
	0.0%	-0.1%	0.0%
Enc Time[%]	100%
Dec Time[%]	99%

	Low delay B LC
	Y	U	V
Class A
Class B	0.0%	0.0%	0.1%
Class C	0.0%	0.0%	-0.1%
Class D	0.0%	0.2%	-0.1%
Class E	0.0%	0.1%	-0.1%
Overall	0.0%	0.1%	-0.1%
	0.0%	0.0%	-0.1%
Enc Time[%]	100%
Dec Time[%]	98%