Image split, rearrange. QLabel best way to display?

[fire]

I have seen another post where someone wanted to split an image into 4 pieces, rearrange them and put back into display.

I am interested in taking an image, removing the bottom pixel line, and moving it to the top of the image. I would like to have this in a loop so the picture is rotating from bottom to top continually (basically making an image marquee).

I have had success in using QLabel to display the picture, using third party code to copy the bottom to top, save the file, then re-read the file into QLabel. However the process is slow and I am looking for a faster alternative.

I thought I could use QImage::copy() but I don't understand how I can rearrange the copied portions and save as a new QImage for display.