Rate and Quality Control With Embedded Coding for Mobile Robot With Visual Patrol

Abstract

The visual information of a surveillance system should provide extended and just-in-time perception in monitored environments. However, delivering visual information of surveillance from nonstationary providers, such as mobile cameras, to designated end-users over bandwidth-limited networks is a challenging task. In this paper, for transmitting visual objects of interest, an embedded spatial coding approach is proposed to progressively encode the presentation quality of visual objects under receivers' bandwidth limitation. First, different levels of importance for the objects of interest are characterized by the standard edge detection algorithm and several designated priorities for these objects are progressively assigned. The spatial coding approach then adopts a wavelet-based image coding algorithm based on the assigned priority of each object of interest. Therefore, each individual receiver can adaptively obtain the best visual information of the most important object under its available bandwidth. The proposed priority assignment and spatial coding mechanism has been extensively tested and analyzed. The experimental results show that, under different bandwidth scenarios and required acceptable signal-quality levels, the end-users can obtain the best visual quality of the important objects of interest. Therefore, the importance of the objects of interest in real-time surveillance video can be properly determined and the required transmission quantity can be effectively allocated.