National Yang Ming Chiao Tung University

Industrial Technology Research Institute

Mitsubishi Electric Research Laboratories, Inc.

Chung-Neng Wang

Tihao Chiang

Shih-Hao Wang

Hsueh-Ming Hang

Ming-Yen Huang

Hsiang-Chun Huang

Tzu-Liang Su

Anthony Vetro

Huifang Sun

Yao-Chung Lin

Ti-Hao Chiang

Shin-Wei Yang

Chi-Min Liu

Jeng-Hung Luo

Gen-Ming Lee

An MPEG-4 system with error concealment is provided for video service under the network with packet loss. The MPEG-4 system includes an encoder and a decoder. The encoder uses an intra-refreshment technique is used to make coded bitstream more robust against noise in order to stop error propagation. The rate-distortion optimization criterion is also introduced to adaptively update in synchronization with intra-coded blocks adaptively based on the true network condition with minimal overhead. The Lagrange multiplier is modified to achieve the best rate-distortion balance. In addition, a decoder loop is used in the encoder and is synchronized with the true decoder to achieve the best performance and avoid mismatch with the decoder used in the MPEG-4 system. The decoder is able to achieve resilient decoding from any kind of noise and enhance the reconstructed image quality with spatial and temporal hybrid concealment method. The result shows that a 3.65-9.71 dB further improvement on peak-signal-to-noise-ratio (PSNR) can be achieved in comparison with the existing methods that adopt spatial copy and zero motion concealment in decoding.

MPEG-4 streaming system with adaptive error concealment

A method transcodes a compressed multi-layer video bitstream that includes a base layer bitstream and an enhancement layer bitstream. The base and enhancement layers are first partially decoded, and then the partially decoded signals are combined with a motion compensated signal yielding a combined signal. The combined signal is quantized into an output signal according to a quantization parameter, and the output signal is variable length encoded as a single layer bitstream. In a preprocessing step, the enhancement layer can be truncated according to rate control constraint, and the same constraints can also be used during the quantization.

Video transcoding of scalable multi-layer videos to single layer video

A robust fine granularity scalability video encoding includes a base layer encoder and an enhancement layer encoder in which motion compensated difference images are generated by comparing an original image to predicted images at base layer and enhancement layer with motion compensation. Based on leaky and partial predictions, a high quality reference image is constructed at the enhancement layer to improve temporal prediction. In the construction of the high quality reference image, one parameter &#x3b2; controls the number of bitplanes of the enhancement layer difference coefficients used and another parameter &#x3b1; controls the amount of predictive leak. A spatial scalability module allows the processed pictures at the base layer and the enhancement layer to have identical or different spatial resolutions.

Architecture and method for fine granularity scalable video coding

The present invention proposes a fast motion estimation using N-queen pixel decimation, whereby after a reference block and a block to be processed are selected in a video sequence, an N&#xd7;N queens pattern is used for pixel decimation to perform block match, thereby obtaining a good enough block difference value. The present invention combines pixel decimation with fast motion estimation for search points reduction to achieve the object of simplifying computational complexity of motion estimation. Therefore, the present invention can sieve out sufficiently representative pixels and will not increase extra computational complexity.

Fast motion estimation using N-queen pixel decimation

A method of motion estimation for video encoding constructs a binary pyramid structure having three binary layers. A state update module registers and updates repeat occurrence of final motion vectors and a static-state checking module determines if the method is in a static mode or a normal mode based on the repeat occurrence. In a normal mode, the first binary layer is searched within a &#xb1;3 pixel refinement window to determine a first level motion vector. In the second binary layer, a search range is computed based on six motion vector candidates. By checking every point within in the search range, a second binary layer search generates a second level motion vector. Finally, a third binary layer search within a &#xb1;2 pixel refinement window generates a final motion vector according to the second level motion vector. In a static mode, a fine tuning module performs search within a &#xb1;1 pixel refinement window and generates a final motion vector.

Method and apparatus for motion estimation with all binary representation

Growing community of inventors

Kaohsiung, Taiwan

Chung-Neng Wang