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—A new rate control scheme for H.264 video encoding with enhanced rate and distortion models is proposed in this work. Compared with existing H.264 rate control schemes, our scheme has offered several new features. First, the inter-dependency between rate-distortion optimization (RDO) and rate control in H.264 is resolved via quantization parameter(More)
The visual quality of compressed images and video is Low bit rate image/video coding is essential for many visual generally affected by three factors: data source, coding bit communication applications. When bit rates become low, most rates, and compression algorithms. For a given compres-compression algorithms yield visually annoying artifacts that sion(More)
A quad-tree decomposition approach is proposed for cartoon image compression in this work. The proposed algorithm achieves excellent coding performance by using a unique quad-tree decomposition and shape coding method along with a GIF like color indexing technique to efficiently encode large areas of the same color, which appear in a cartoon-type image(More)
Dedication To m y parents ii Acknowledgments I w ould like to express my deep appreciation to my advisor, Prof. Antonio Ortega, for his valuable advice, muniicent helps, and friendship during the essential stage of my study. I also would like to express my deep gratitude to Prof. C.-C. Jay Kuo, for his generous support, constant encouragement and friendship(More)
A fast inter-prediction mode decision and motion search algorithm is proposed for the H.264 video coding standard. The multi-resolution motion estimation scheme and an adaptive rate-distortion model are employed with early termination rules to accelerate the search process. With the new algorithm, the amount of computation involved in the motion search can(More)
Progressive coding of 3D textured graphic models using a joint mesh-texture optimization technique is investigated in this work. The mesh and texture data of a model are first fed into their respective compression modules to result in a series of levels of details. Then, for a given viewpoint, a rate-distortion surface is generated using these mesh and(More)
A new blind inverse halftoning algorithm based on a nonlinear filtering technique of low computational complexity and low memory requirement is proposed in this research. It is called blind since we do not require the knowledge of the halftone kernel. The proposed scheme performs nonlinear filtering in conjunction with edge enhancement to improve the(More)
— An image registration technique for compressed video such as motion JPEG or the I-picture of MPEG is investigated in this paper. The proposed technique is based on the DCT (Discrete Cosine Transform) coefficient matching. First, the coarse edge features are extracted by applying several edge detectors to luminance DC coefficients. Each detector generates(More)
A computationally ecient postprocessing technique to reduce compression artifacts in low-bit-rate video coding is proposed in this paper. Blocking and ringing eeects are two majors artifacts observed in block DCT-based codec, such as H.263, when coding at very low bit rates. Reduction of these artifacts can signiicantly improve the overall visual quality of(More)