[XviD-devel] GMC

[skal]

	Tushit,

On Tue, 2004-12-07 at 10:54, Tushit Bharthuar wrote:
> Hi,
> 
> When we are calculating offset, should not the offset
> be restricted by the image size?
> e.g. In the case of Predict_16x16_C if v>=H Offset
> becomes image height multiplied by the source stride.
> which is outside the image.

	Actually, it's not really "outside" the
	image, but rather exactly on the bottom/right
	boundary.
	Offset remains strictly in [0,H]. Since edges
	are replicated, we can nevertheless read
	source and weight it even if offset=H.
	Note that in such case, the weight for pixel
	"Offset" is 1, and the weight for pixel "Offset+1"
	is 0. Hence, even if we read outside the image,
	the result is zeroed by the null weight.

	hope it helps,
Skal