Programmatically change image resolution

Question

I have calculated that if I want my generated image to be A4 size @ 600dpi for print purpose, it needs to be 7016x4961px @ 72dpi. So, I generate it programmatically, then test

Answer 1

This code will resize a PNG image into 7016x4961 with PIL:

size = 7016, 4961
im = Image.open("my_image.png")
im_resized = im.resize(size, Image.ANTIALIAS)
im_resized.save("my_image_resized.png", "PNG")

Perhaps a better approach would be to make your canvas x times bigger prior to printing, where x is a factor you have to figure out (7016x4961 in size for this particular image).