Progressive image coding with spatially variable resolution

摘要

We present a wavelet-based progressive image coding system that allows the specification of regions of interest to alter the spatial allocation of future transmitted bits. When used in an interactive mode with feedback, the viewer, after seeing a low resolution version of the image, can instruct the encoder to concentrate more effort on coding regions of interest. When operating in an independent mode, the encoder can select regions of interest based on automatic feature recognition algorithms or offline human selection. The algorithm is flexible enough to adapt to changes of interest during encoding.