Article

Model-Aided Coding: Using 3-D Scene Models in Motion-Compensated Video Coding

Telecommun. Lab., Erlangen-Nurnberg Univ.
Proceedings / ICIP ... International Conference on Image Processing 06/2002; DOI: 10.1109/ICIP.2000.899314
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ABSTRACT We show that traditional waveform-coding and 3-D modelbased coding are not competing alternatives but should be combined to support and complement each other. Both approaches are combined such that the generality of waveform coding and the e#ciency of 3-D model-based coding are available where needed. The combination is achieved by providing the block-based video coder with a second reference frame for prediction which is synthesized by the model-based coder. Since the coding gain of this approach is directly related to the quality of the synthetic frame, we have extended the model-aided coder [1] to exploit knowledge about illumination changes and multiple objects. Remaining model failures and objects that are not known at the decoder are handled by standard block-based motioncompensated prediction. A Lagrangian approach is employed to control the coder. Experimental results show that bit-rate savings of about 35 % are achieved at equal average PSNR when comparing the model-aided codec to TMN-10, the state-of-the-art test model of the H.263 standard.

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