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.