Patch tool appears to have blend applied to replacement

[StuartPearson]

When using the patch tool, when the selection is moved there appears to be a blend applied to the displayed image, it is even more noticeable if you use the tool at the edge of an image. I would have expected the patched area to have exactly the same content as the copied area 

Stuart

[Chris B]

Hey Stuart,

I logged this last year with the developers however it was closed as by design due to the image I was testing it on. The image in your video is also similar as in there are so many tones, shades and colours that the algorithm is indeed trying to blend them together. If for example, you attempted removing a cluster of blemishes from a cheek, you should see no such issue.

[StuartPearson]

On 1/20/2020 at 2:34 PM, Chris B said:

Hey Stuart,

I logged this last year with the developers however it was closed as by design due to the image I was testing it on. The image in your video is also similar as in there are so many tones, shades and colours that the algorithm is indeed trying to blend them together. If for example, you attempted removing a cluster of blemishes from a cheek, you should see no such issue.

I was under the impression that the patch tool with blend set at normal should just be effectively copying the pixels from the source so should be an exact copy. I don’t see where an algorithm would be involved.

[Chris B]

I imagine it attempts to blend the surrounding pixels of the selected area with the destination pixels. If they differ greatly, the algorithm gets confused and starts bringing in random colours. 

The tool works fine when using it to remove a blemish from a skin tone but in your video, you have blues, whites, browns, greys and yellows within the selected area so I think you're asking too much from the tool and this isn't typically what it would be used for. The tools primary use is for repairing damaged areas of an image. 

[StuartPearson]

Thanks for the info, I was misunderstanding the patch function, I have just read the inbuilt help on it and it confirms the blending. Explains other occasions why it hasn’t behaved how I expected it to  

[Chris B]

No worries! I think the help often gets overlooked or is forgotten about, which is a shame because it is really handy and I refer to it all the time