Resizing an image (to a lower scale) without loosing quality

Good Day everyone I am looking for a way to make an image samller by a certain factor, but at the same time NOT TO diminish the quality of the image.

So far I have tried using

StreatchBlt API function and
.PaintPicture

but both of these methods noticeably diminish the quality of the image when the original images is resized to a lower scale

I appreciate any of your input

Thank you
.

There is no way that you can keep the same quality... I use StretchBlt and SetStretchBltMode to set the stretching mode to HALFTONE (that is the best solution I found so far, at least im my case)
Marco