| Abstract |
In order to efficiently archive and transmit large 3D models, lossy
and lossless compression methods are needed. We propose a compression scheme
for coordinate data of point-based 3D models of surfaces. A point-based model
is processed for compression in a pipeline of three subsequent operations,
partitioning, parameterization, and coding. First the point set is partitioned
yielding a suitable number of point clusters. Each cluster corresponds to a
surface patch, that can be parameterized as a height field and resampled on a
regular grid. The domains of the height fields have irregular shapes that are
encoded losslessly. The height fields themselves are encoded using a
shape-adaptive wavelet coder, producing a progressive bitstream for each patch.
A rate-distortion optimization provides for an optimal bit allocation for the
individual patch codes. With this algorithm design
compact codes are produced that are scalable with respect to rate, quality, and
resolution. In our encodings of complex 3D models competitive rate-distortion
performances were achieved with excellent reconstruction quality at under 3
bits per point (bpp). |