A multiresolution approach for blind watermarking of 3D meshes using spiral scanning method

Abstract

During the last decade, the flow of 3D objects is increasingly used everywhere. This wide range of applications and the necessity to exchange 3D meshes via internet raise major security problems. As a solution, we propose a blind watermarking algorithm for 3D multi-resolution meshes ensuring a good compromise between invisibility, insertion rate and robustness while minimizing the amount of memory used during the execution of our algorithm. To this end, spiral scanning method is applied. It decomposes the mesh into GOTs (a Group Of Triangles). At each time, only one GOT will be loaded into memory to be watermarked. It undergoes a wavelet transform, a modulation then embedding data. Once finished, the memory will be released to upload the next GOT. This process is stopped when the entire mesh is watermarked. Experimental tests showed that the quality of watermarked meshes is kept despite the high insertion rate used and that memory consumption is very reduced (until 24% of memory reduction). As for the robustness, our algorithm overcomes the most popular attacks in particular compression. A comparison with literature showed that our algorithm gives better results than those recently published.