35,496 research outputs found
An Efficient Mode Decision Algorithm Based on Dynamic Grouping and Adaptive Adjustment for H.264/AVC
“This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.”The rate distortion optimization (RDO) enabled mode decision (MD) is one of the most important techniques introduced by H.264/AVC. By adopting the exhaustive calculation of rate distortion, the optimal MD enhances the video encoding quality. However, the computational complexity is significantly increased, which is a key challenge for real-time and low power consumption applications. This paper presents a new fast MD algorithm for highly efficient H.264/AVC encoder. The proposed algorithm employs a dynamic group of candidate inter/intra modes to reduce the computational cost. In order to minimize the performance loss incurred by improper mode selection for the previously encoded frames, an adaptive adjustment scheme based on the undulation of bitrate and PSNR is suggested. Experimental results show that the proposed algorithm reduces the encoding time by 35% on average, and the loss of PSNR is usually limited in 0.1 dB with less than 1% increase of bitrate
An efficient fast mode decision algorithm for H.264/AVC intra/inter predictions
H.264/AVC is the newest video coding standard, which outperforms the former standards in video coding efficiency in terms of improved video quality and decreased bitrate. Variable block size based mode decision (MD) with rate distortion optimization (RDO) is one of the most impressive new techniques employed in H.264/AVC. However, the improvement on performance is achieved at the expense of significantly increased computational complexity, which is a key challenge for real-time applications. An efficient fast mode decision algorithm is then proposed in this paper. By exploiting the correlation between macroblocks and the statistical characteristics of sub-macroblock in MD, the video encoding time can be reduced 52.19% on average. Furthermore, the motion speed based adjustment scheme was introduced to minimize the degradation of performanc
On the algebra A_{\hbar,\eta}(osp(2|2)^{(2)}) and free boson representations
A two-parameter quantum deformation of the affine Lie super algebra
is introduced and studied in some detail. This algebra is the
first example associated with nonsimply-laced and twisted root systems of a
quantum current algebra with the structure of a so-called infinite Hopf family
of (super)algebras. A representation of this algebra at is realized in
the product Fock space of two commuting sets of Heisenberg algebras.Comment: 14 pages, LaTe
q-deformed Supersymmetric t-J Model with a Boundary
The q-deformed supersymmetric t-J model on a semi-infinite lattice is
diagonalized by using the level-one vertex operators of the quantum affine
superalgebra . We give the bosonization of the boundary
states. We give an integral expression of the correlation functions of the
boundary model, and derive the difference equations which they satisfy.Comment: LaTex file 18 page
Propagating wave in active region-loops, located over the solar disk observed by the Interface Region Imaging Spectrograph
We aim to ascertain the physical parameters of a propagating wave over the
solar disk detected by the Interface Region Imaging Spectrograph (IRIS). Using
imaging data from the IRIS and the Solar Dynamic Observatory (SDO), we tracked
bright spots to determine the parameters of a propagating transverse wave in
active region (AR) loops triggered by activation of a filament. Deriving the
Doppler velocity of Si IV line from spectral observations of IRIS, we have
determined the rotating directions of active region loops which are relevant to
the wave. On 2015 December 19, a filament was located on the polarity inversion
line of the NOAA AR 12470. The filament was activated and then caused a C 1.1
two-ribbon flare. Between the flare ribbons, two rotation motions of a set of
bright loops were observed to appear in turn with opposite directions.
Following the end of the second rotation, a propagating wave and an associated
transverse oscillation were detected in these bright loops. In 1400 A channel,
there was bright material flowing along the loops in a wave-like manner, with a
period of ~128 s and a mean amplitude of ~880 km. For the transverse
oscillation, we tracked a given loop and determine the transverse positions of
the tracking loop in a limited longitudinal range. In both of 1400 A and 171 A
channels, approximately four periods are distinguished during the transverse
oscillation. The mean period of the oscillation is estimated as ~143 s and the
displacement amplitude as between ~1370 km and ~690 km. We interpret these
oscillations as a propagating kink wave and obtain its speed of ~1400 km s-1.
Our observations reveal that a flare associated with filament activation could
trigger a kink propagating wave in active region loops over the solar disk.Comment: Accepted for publication in A&
Eigenvalues of Ruijsenaars-Schneider models associated with root system in Bethe ansatz formalism
Ruijsenaars-Schneider models associated with root system with a
discrete coupling constant are studied. The eigenvalues of the Hamiltonian are
givein in terms of the Bethe ansatz formulas. Taking the "non-relativistic"
limit, we obtain the spectrum of the corresponding Calogero-Moser systems in
the third formulas of Felder et al [20].Comment: Latex file, 25 page
Measuring the Fourth Generation b --> s Quadrangle at the LHC
We show that simultaneous precision measurement of the CP-violating phase in
time-dependent Bs --> J/psi phi study and the Bs --> mu+ mu- rate, together
with measuring m_t' by direct search at the LHC, would determine
V_{t's}^*V_{t'b} and therefore the b --> s quadrangle in the four-generation
standard model. The forward-backward asymmetry in B --> K* l+ l- provides
further discrimination.Comment: 6 pages, 7 figures, revised based on LHC results released in this
summer, to appear in PR
Infinite Hopf family of elliptic algebras and bosonization
Elliptic current algebras E_{q,p}(\hat{g}) for arbitrary simply laced finite
dimensional Lie algebra g are defined and their co-algebraic structures are
studied. It is shown that under the Drinfeld like comultiplications, the
algebra E_{q,p}(\hat{g}) is not co-closed for any g. However putting the
algebras E_{q,p}(\hat{g}) with different deformation parameters together, we
can establish a structure of infinite Hopf family of algebras. The level 1
bosonic realization for the algebra E_{q,p}(\hat{g}) is also established.Comment: LaTeX, 11 pages. This is the new and final versio
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