What if one makes an small contribution through independent study? Will that be sufficient to be granted a Phd? I do hear that some universities offer a PhD by

What if one makes an small contribution through independent study? Will that be sufficient to be granted a Phd? I do hear that some universities offer a PhD by publishing, wherein they grant a degree for already published work. Perhaps a bit like the film making model whose name presently eludes me, where instead of trying to get a funding from a studio to make a film, the filmmakers make it out of their own resource arrangements, and later try to sell the finished film to studios (perhaps for a profit).