The VP8 is not adding any additional information, but simply decoding what is on the shroud. Further, there are other methods besides the VP8 to generate a 3D image from the shroud, so it’s not just the algorithm in the VP8.
Actually, the concept is simple and you can even observe it with your naked eye. The distance is proportional to the darkness, which is proportional to the density of the dots. This was even observed by early shroud researcher Paul Vignon in 1902.
Some emanation from the body has acted on the linen, and since the hollows on the Shroud are less vigorously reproduced than the raised portions it must be admitted that this something worked with less intensity in proportion as the distance from the body increased … it is indeed hard to determine with what rapidity the unknown action took place between the body and the Shroud; the main point is that we can assert that the action diminished in proportion as the distance of the body from the Shroud increased.
Though his theory as to what caused it was wrong, he was right in observing there is depth information on the shroud.
In 1974, Paul Gastineau had invented a device to photomechanically extract the information and got this result:
In 1974 a Frenchman, Ing. PAUL GASTINEAU, made a negative relief mold using his own system. This technique consisted in having every single point on the Enrie photograph of the face examined using his own equipment and a concentrated light source; the measurements of the quantity of light which was more or less reflected was transmitted to another part of the instrument , which contained a white-hot point that at the same time engraved the image into a soft material, thus visualizing this hidden information and obtaining a three dimensional Sindonic face.
In 2005, Petrus Soons used computer software to extract the depth information and created a hologram of the shroud.
Then in 2005 Dr. PETRUS SOONS, aware of the fact that there was hidden 3D information in the grayscale of the image of the body of Jesus, used this information, and with his team of experts he recreated the body in 3D in the computer, and this information was then used to create Holograms (3D images in LIGHT) of the Shroud including the 3D image of the face and the front and the back of the body. In 2006 these holograms were produced with the original measurements (200 x 100 cm) in the Shroud.
So, the only thing you have to do is measure the darkness of the image to determine the depth. But, this is harder than it sounds because the cloth was not a flat surface which would cause distortions. Also, the shroud is not a photographic plate and has many imperfections in it.