> What do you mean by "this is a lot circumstantial?"
to add first a crop frame to each picture
The ratio of 4:3 is 1.33333333333333, and the ratio of 16:9 is 1.7777777777777... There would definitely be significant warping of your image unless you set a 16:9 crop on your image first.
the reason is this, that I have stillimages captures from a video, these are saved in wrong proportions, so the need to be streched!
in irfanview, e.g. I ve to disable this option:
"Preserve aspect ratio"