For Full-Text PDF, please login, if you are a member of IEICE,|
or go to Pay Per View on menu list, if you are a nonmember of IEICE.
New Rate Control Method with Minimum Skipped Frames for Very Low Delay in H.263+ Codec
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences
Publication Date: 2002/06/01
Print ISSN: 0916-8508
Type of Manuscript: PAPER
H.263+, rate control, optimum bit allocation, low encoder-decoder delay, lip synchronization,
Full Text: PDF>>
A new H.263+ rate control method that has very low encoder-decoder delay, small buffer and low computational complexity for hardware realization is proposed in this paper. This method focuses on producing low encoder-decoder delay in order to solve the lip synchronization problem. Low encoder-decoder delay is achieved by improving target bit rate achievement and reducing processing delay. The target bit rate achievement is improved by allocating an optimum frame encoding bits, and employing a new adaptive threshold of zero vector motion estimation. The processing delay is reduced by simplifying quantization parameter computation, applying a new non-zero coefficient distortion measure and utilizing previous frame information in current frame encoding. The simulation results indicate very large number skipped frames reduction in comparison with the test model TMN8. There were 80 skipped frames less than that of TMN8 within a 380 frame sequence during encoding of a very high movement video sequence. The 27 kbps target bit rate is achieved with insignificant difference for various types of video sequences. The simulation results also show that our method successfully allocates encoding bits, maintains small data at the encoder buffer and avoids buffer from overflow and underflow.