Abstract: A video conference system based on a surveillance system is disclosed. According to one aspect of the system, there is a surveillance system including a monitoring server and a streaming media server. A gateway is provided to for protocol conversion between a meeting terminal and the monitoring server as well as between a meeting terminal and the streaming media server to facilitate seamless transmission of signal and media streams among all meeting participants (e.g., terminal devices). In addition an audio mixing point and a video forwarding point are created for a meeting to facilitate the data exchange among all meeting participants.

Abstract: Techniques pertaining to scalable video codec are disclosed. According to one aspect of the present invention, a video image is analyzed and a region of interest (ROI) and a region of non-interest (non-ROI) are identified. By comparing the non-ROI image with that of a previous image, a background ignored identifier is created indicating whether the non-ROI can be ignored during encoding and decoding processes. Based on the status of the background ignored identifier, the encoder encodes the images into a basic layer (BL) and an enhanced layer (EL), and transmits the coded bit streams along with the identifier to a decoder. The decoder reconstructs the image based on the identifier and the BL and the EL bit streams.

Abstract: Techniques pertaining to noise reduction are disclosed. According to one aspect of the present invention, noise in an audio signal is effectively reduced and a high quality of a target voice is recovered at the same time. In one embodiment, an array of microphones is used to sample the audio signal embedded with noise. The samples are processed according to a beamforming technique to get a signal with an enhanced target voice. A target voice is located in the audio signal sampled by the microphone array. A credibility of the target voice is determined when the target voice is located. The voice presence probability is weighted by the credibility. The signal with the enhanced target voice is enhanced according to the weighed voice presence probability.

Abstract: Techniques for enhancing bass effects in an audio signal are described. According to one embodiment, an audio input signal is filtered to produce a low frequency component thereof (a low frequency signal of the audio input signal). The low frequency signal expressed in time domain is transformed to a corresponding spectrum expression in frequency domain. A fundamental frequency signal of the low frequency signal in the frequency domain is determined to generate a plurality of harmonics that are then transformed back to the time domain. Both the audio input signal (delayed) and the harmonics are synthesized to produce an audio output signal whose bass is greatly enhanced.