Why can't you overlay an image onto a video without losing any quality?

[deama]

So basically, I don't quite understand why you can't just overlay an image ontop of a video without having to render it? Can't you just like splice them ontop of each other or something? Or maybe you can convert the image into a video and just splice it with the actual video? Would that work?

[feisty2]

ur talkin about structured data, encoded videos and images are, unfortunately, unstructured data. There're structured formats for intermediate copies, like you could manipulate different layers of image in a psd file, that information is however, permanently lost once you convert it to a final tiff copy or a lesser jpg copy