Noise reduction reflection along borders

[Lawrence37]

Noise reduction in the details panel and local adjustments panel creates a small reflection along the borders of the image. It is most apparent on the right and bottom sides. The changes on the other sides are subtle and are best visualized using the local adjustments noise reduction with the mask set to "Show modified areas". The issue is sensitive to the position of the preview. If you can't reproduce it, pan around a little.

Steps to reproduce

1. Enable noise reduction.
2. Set Luminance amount to 0.39 or greater.
3. Zoom to the right or bottom edge of the image at >=100% magnification.

Here I've also disabled the chrominance NR so that the before/after is clear.

[Desmis]

We find this behavior also in Wavelet levels (and without denoise), but is this behavior recent ?

On the other hand it is not found in "LA wavelet".

I tried to find out what could be the cause, after excluding the obvious differences as for example the tiles.

One of the tracks that I think is possible that represents "The" real difference between these wavelets is:

• In Denoise (main), Wavelet Level, LA denoise the decomposition of the 3 channels L, a, b (or r,g,b) is done or used at the same time as a block, which allows (in a way) to optimize code and memory.
• In "LA wavelet" it's done separately......

but is this it ???

Jacques