You are not loading correct. Dont' load your file into the picture, but into the declared format
There where issus with transparent images and loading them into a TImage. I dont know if they are fixed now. That's why I load explicit
img.Picture.PNG.LoadFromFile (....
On the other hand, that was one point to start using BGRA: the handling of transparency is easy and clear. And at the end of your operations you can just draw it on a TImage - with transpareny.
Winni
Image.Picture.SaveToClipboardFormat(CF_Bitmap);
So your code might look like this: