Replace transparency in PNG images with white background

Question

I\'ve got some PNG images with transparency, and I need to create versions with the image layer composed onto a white background. I\'ve tried various things with Image Magi

Answer 1

this creates an image just placing the 1st with transparency on top of the 2nd

composite -gravity center ImgWithTransp.png BackgroundSameSizeOfImg.png ResultImg.png

originally found the tip on this post