Abstract: A method and system for a rate control block that adjusts the Quantization Parameter (QP) for a frame or macroblock based on the number of bits already used in encoding the frame or macroblock is disclosed. In an embodiment of the invention, the QP for a macroblock is adjusted dynamically against the QP for a frame as a function of the buffer occupancy. In another embodiment of the invention, a range of allowable QPs are defined based on the buffer occupancy. Embodiments of the invention are applicable to H.264 high-definition video conferencing.