An excellent illustration of what might occur if a drink spills all over a priceless photo or a water pipe bursts. Although there are a lot of do-it-yourself tips available for restoring a photograph that has gotten wet and adhered to glass, the Smithsonian Institute Archive strongly advises against attempting to remove a photograph that has been adhered to glass by yourself.
This includes attempting to remove a photo from glass by heating it with a hairdryer, freezing it, or using a microwave oven. Rather, they advise leaving the restoration of these kinds of photos to skilled restoration specialists.
If a photograph is too damaged by broken pieces, moisture, or debris, or if it cannot be detached from the glass, it can be repaired by creating a high-quality scan and using digital retouching to repair the damages to the image and making a new print to replace the damaged original.