THREE-DIMENSIONAL SIMULATION OF VOLUME PICTORIAL HOLOGRAM BY PHOTOGRAMMETRY METHOD

Subject of Research. The digitizing possibility for pictorial holograms is considered aimed at their storage and processing with the use of digital technologies. A novel method is proposed for application of photogrammetric technology with the view to create digital images from holograms. The prospects of obtaining a digital copy are discussed by applying a series of photographs and processing software package. Method. The ceramic sculpture with 89 mm height was chosen as an object for the experiment. Two pictorial sculpture holograms were recorded from the back and front sides by He-Ne laser at the wavelength λ = 633 nm with the power P = 50 mW for 90 seconds. A photograph of the object was taken as it rotates around its axis with a step of 1.8°. The Canon EOS 1100D camera with a resolution of 12.2 million pixels was selected for photography. A series of 300 photos was performed. For recovery of images registered on volume monochrome holograms, a point source of white scattered light was used inclined at an angle of 45° to the normal of the plate. Ninety photos of each hologram were obtained with an angle area coverage of 120°. The sculpture and holograms were photographed around the object at the angles equal to 0 and 45°. Agisoft PhotoScan (version 1.4.5) software was used as a processing software package for a series of photographs. The volume of the processed files was about 4.5 GB. Main Results. The results of a 3D model restoration from two holograms of the same object are presented. Comparative analysis of the obtained 3D-models of the image is carried out. It is shown that the hologram volume model created by photogrammetric method has a visual difference from the model of the object itself. The 3D model quality improvement depends on increasing the number of recorded phase holograms of the same object from different angles. Practical Relevance. The proposed digitizing method for the holograms through the use of photogrammetry technology can find practical application for solving problems in the field of long-term storage of information about cultural heritage sites