DEVICE AND METHOD FOR RECEIVING VIDEO DATA

摘要

The device and method according to the invention prevent that the consistency of image quality is negatively affected when transmission rate fluctuations occur on a communication channel. The invention relies on the perception that the transition from a full quality video signal to a basic-quality video signal, respectively from a basic-quality video signal to a full-quality video signal, should be a gradual transition instead of a sudden transition. The blending process can be implemented by circuitry which applies a blending factor on the decoded video signals of the base layer and the enhancement layer(s), before these decoded video signals are merged to form a single output video signal. Due to the delay time of the decoding process there will be a natural delay between the moment a transition occurs in the received video data and the moment that a transition occurs in the full-quality video signal. During that time interval the blending factor may be changed gradually, so that the visibility of the transition is reduced. It may be preferable to provide for an extra delay in addition to this natural delay. This enables the device to further smooth away the effect of the quality transition in the received video data.