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91.
Many evolving video services and applications for intelligent security systems require reliable transmission of high quality
video to diverse clients over heterogeneous networks using available system resources. Scalable video coding (SVC) is one
of the emerging video compression technologies with such potential capabilities. Advances in lifting-based motion-compensated
temporal filtering (MCTF) have enabled highly efficient and flexible spatial, temporal, signal-to-noise ratio (SNR), and complexity
scalability to be realized over a wide range of bit rates. In this paper, we present an algorithm to improve the update step
of MCTF, which serves as an important informative step for the coding performance of SVC. A novel update-step algorithm, which
takes advantage of the chrominance information of the video sequence and the correlation of the motion vectors (MVs) of the
neighboring blocks as well as the correlation of the derived update MVs in the low-pass frames, is proposed to improve update
step of MCTF by (1) computing correct update motion information, (2) generating correct amount of energy contained in the
high-pass frames. Experimental results show that the proposed algorithm can significantly improve the quality of the reconstructed
video sequence in visual quality.
相似文献
Xiaokang YangEmail: |
92.
A device design methodology for sub-100-nm SOC applications using bulk and SOI MOSFETs 总被引:1,自引:0,他引:1
CMOS for the mixed-mode applications has gained much interest recently. While the International Technology Roadmap for Semiconductors provides two different scaling guidelines for the analog and digital circuit operation using the bulk MOSFET, there are no well-defined scaling guidelines for improving the analog performance of silicon-on-insulator (SOI) MOSFETs. This paper presents a systematic and quantitative comparison between the analog characteristics of the bulk and SOI technology. The intrinsic gain, f/sub T/ and g/sub m//I/sub ds/ ratio are considered as a metric for this comparison. It is shown that, even for the operating frequencies in the range of gigahertz (where the ac kink effect is suppressed), analog performance of SOI devices is inferior to that of the bulk devices due to the capacitive drain-to-body coupling. Based on our study, we show that hat the gate-workfunction engineering (close to mid-gap workfunction) is essential in fully depleted SOI (FDSOI) devices for improving analog performance. The analog performance of partially depleted SOI (PDSOI) devices can be improved by using body-tied structures. An increased gate control in double-gate MOSFETs can provide very high output resistance for short-channel devices. 相似文献
93.
Yoo SK Wang G Collison F Rubinstein JT Vannier MW Kim HJ Kim NH 《IEEE transactions on bio-medical engineering》2004,51(5):838-846
Three-dimensional (3-D) localization of individual cochlear implant electrodes within the inner ear is of importance for modeling the electrical field of the cochlea, designing the electrode array, and programming the associated speech processor. A 3-D reconstruction method of cochlear implant electrodes is proposed to localize individual electrodes from two X-ray views in combination with the spiral computed tomography technique. By adapting epipolar geometry to the configuration of an X-ray imaging system, we estimate individual electrode locations in the least square sense without using a patient attachment required by an existing stereophotogrammetry technique. Furthermore, our method does not require any knowledge of the intrinsic and extrinsic parameters of the imaging system. The performance of our method is studied in numerical simulation and with patient data and is found to be sufficiently accurate for clinical use. The maximum root mean-square errors measured are 0.0445 and 0.214 mm for numerical simulation and patient data, respectively. 相似文献
94.
With video compression standards such as MPEG‐4, a transmission error happens in a video‐packet basis, rather than in a macroblock basis. In this context, we propose a semantic error prioritization method that determines the size of a video packet based on the importance of its contents. A video packet length is made to be short for an important area such as a facial area in order to reduce the possibility of error accumulation. To facilitate the semantic error prioritization, an efficient hardware algorithm for face tracking is proposed. The increase of hardware complexity is minimal because a motion estimation engine is efficiently re‐used for face tracking. Experimental results demonstrate that the facial area is well protected with the proposed scheme. 相似文献
95.
96.
Hong Chae Woo 《Electronics letters》1998,34(13):1300-1301
The performance of a stochastic gradient adaptive filter can be significantly improved by introducing a forgetting factor. The complexity of the original algorithm can also be reduced by using only the signs of error signals and input signals in the gradient adaptive step size computation 相似文献
97.
The implementation of TS MAC system for KOREASAT DBS (direct broadcast satellite) system is presented. This TS MAC controls and monitors the status of the TS equipment and gathers the alarm for them. The advantage of this system is the center-concentrated, real time processing, remote control, and object oriented module decomposing 相似文献
98.
Swee Chuan Tjin Seng Lee Ng Kian Thiam Soo 《IEEE transactions on bio-medical engineering》1998,45(10):1272-1278
A new fiber-optic catheter for in vivo blood-flow measurements has been developed. The catheter is designed to measure blood flow in both the forward (toward the catheter tip) and reverse (away from the catheter tip) flow directions. It consists of two multimode optical fibers with core diameter of 50 μm and cladding diameter of 125 μm. One fiber transmits the laser beam into blood and the other receives the backscattered light from the erythrocytes within the probe volume. In the flow experiment, it was found that the flow within the boundary layer is indeed laminar and, hence, the relationship between the Doppler shift frequencies and the flow velocities is linear, thereby making the linear calibration possible for predicting the free stream flow velocity. Plots of the maximum shift frequency (frequency at which the Doppler spectrum disappeared into the noise spectrum) against the flow velocities are found to be more linear in both the forward and reverse flow directions than that of the dominant shift frequency (frequency with the highest amplitude). These results were reaffirmed by the numerical flow simulation along the catheter side wall 相似文献
99.
Heung Ro Choo Beom-hoan O Chong Dae Park Hyung Mun Kim Jeong Soo Kim Dae Kon Oh Hong Man Kim Kwang Eui Pyun 《Photonics Technology Letters, IEEE》1998,10(5):645-647
The improvement of the linewidth enhancement factor in complex-coupled laser diode (CC-LD), or loss-coupled, was confirmed by measuring the spontaneous emission spectra below threshold from the sidewall of laser diodes. In addition, the serial resistance of the device was measured. The linewidth enhancement factor is improved by the presence of a light absorbing InGaAs grating for loss coupled distributed-feedback (DFB) laser diode (LD). We report the comparison of the linewidth enhancement factors of Fabry-Perot (FP) LD, conventional DFB-LD, and loss coupled DFB-LDs 相似文献
100.
Fast DCT algorithm with fewer multiplication stages 总被引:1,自引:0,他引:1
Yeonsik Jeong Imgeun Lee Hak Soo Kim Kyu Tae Park 《Electronics letters》1998,34(8):723-724
A novel fast DCT scheme with reduced multiplication stages and fewer additions and multiplications is proposed. The proposed algorithm is structured so that most multiplications tend to be performed at the final stage, which reduces the propagation error that could occur in the fixed-point computation. Minimisation of the multiplication stages can further decrease the error 相似文献