Chul Keun Kim

Distributed video coding encoder/decoder complexity sharing method by phase motion estimation algorithm

Distributed video coding is a coding paradigm that allows complexity to be shared between encoder and decoder, in contrast with conventional video coding. To improve coding efficiency, accurate motion estimation in encoder is required. However, the encoder of distributed video coding performs incomplete motion estimation because of increasing complexity. Therefore, coding efficiency is decreased by inefficient local motion estimation. To solve this problem, we propose that the encoder perform a partial motion estimation using the three step search. It is possible to control complexity of encoder and coding efficiency by performance of terminal. The result of the partial motion estimation is transferred to the decoder, and the decoder performs motion estimation within the narrow range. Therefore, complexity of the decoder is decreased and coding efficiency is increased.

Directional filtering for upsampling according to direction information of the base layer in the JVT/SVC codec

When the reconstructed image of the base layer is up-sampled for decoding the enhancement layer of spatial scalability, direction information derived during decoding the spatially lower layer is used. That is direction information used for Intra prediction which is used for up-sampling again. In most cases, it shows 0.1-0.5dB quality improvement in images up-sampled by using directional filtering compared to those up-sampled conventionally. The same interpolation algorithm should be used in both the encoder and decoder.