Digital Light & Color

There is a visible difference between preview and output image frame sharpness in Mat and Frame transformation. The frame of the output image comes out is distinctly blurred.

David

The preview and final image are computed at different resolutions - since the output image is anti-aliased for display it will generally look smoother than the preview image. To judge the true sharpness of the output image, view it at 1:1. At 1:4 which your screen shot indicates, 4x4 groups of image pixels are being averaged to produce each screen pixel.

I can't reproduce it. The frame is tack sharp (at 1:1 viewing).
What settings do you use?

That's true, at 1:1 it is sharp. I should have found that explanation myself.