Apparatus and method for image transmission

摘要

Apparatus and methods for controlling the amount of data used to transmit still images during the transmission of a video sequence from a first to a second location are disclosed. The apparatus of one embodiment comprises encoding means (105) arrange for intraframe encoding still images for transmission and intraframe encoding part or all of selected video sequence frames, calculating means (106) for determining the data size of intraframe encoded video sequence frames and control means (107) for controlling intraframe encoding of still images for transmission in dependence on the determined intraframe encoded size of a previous video sequence frame. The system can be operated in a way so as to remain H.263 compliant. Other embodiments control the data size by adjusting the quantization used for each Macroblock and by reprocessing each Group of Blocks until a desired data size is reached.