In current video coding standard H.264/AVC, pixel prediction is applied to reduce spatial and temporal redundancy existed in video signal. Previously, it has been shown that better coding performance is achieved compared to H.264/AVC by combining inter and intra prediction to generate a more accurate prediction. In this paper, an improved combined prediction scheme is presented which allows the video codec to tune weighted coefficient for inter prediction and intra prediction adaptively to local signal characteristics. In order to avoid additional overhead signalling, statistics of already coded neighboring block is analyzed to predict the weighted coefficients of the combined prediction for current macroblock. Compared to H.264/AVC, coding performance is increased by up to 1.9%. And compared to the latest combined prediction method using spatial-invariant weighted coefficients, simulation results show that the proposed scheme achieves additional coding gain of up to 0.66%.