I think I can explain this is in more simple terms. Whoever created the PDF of the long-form birth certificate created the document out of separate elements: a green security background, signatures, the boxes and the text, etc. The green background was larger than a standard 8 1/2 by 11 piece of paper, so the forger used a “clipping mask” or solid white frame about a 1/4 inch thick, to electronically lay around the edges of the background to make the background the right size. Instead of cropping the image, they applied a mask. It’s kind of like putting the image inside of a thin picture frame, except that the frame is white and can’t be seen. When the mask layer is hidden, the bacground gets bigger. There’s no way that scanning a document would create a clipping mask like this. Therefore, it’s an additional but obvious sign of manipulation. Does that make sense??
Yes. Thanks.