The actual photographs used to create the textures are completely, or almost completely, different from the final textures?
Viewing post in Photorealistic Texture Pack 1 comments
Most of the textures in this pack were 'resynthesized' using the Efros&Leung Texture Synthesis algorithm, which seeds using discrete pixels from the source image and samples a series of neighboring pixels in order to create a completely "new," but visually similar restructuring of the original image. The ones that could not be synthesized this way (like tiles or straight lines) were created using patch-based or edge blending after sampling and extracting areas from a larger photograph