Free-viewpoint depth image based rendering

In 3D TV research, one approach is to employ multiple cameras for creating a 3D multi-view signal with the aim to make interactive free-viewpoint selection possible in 3D TV media. This paper explores a new rendering algorithm that enables to compute a free-viewpoint between two reference views from existing cameras. A unique property is that we perform forward warping for both texture and depth simultaneously. Advantages of our rendering are manyfold. First, resampling artifacts are filled in by inverse warping. Second, disocclusions are processed while omitting warping of edges at high discontinuities. Third, our disocclusion inpainting approach explicitly uses depth information. We obtain an average PSNR gain of 3 dB and 4.5 dB for the ‘Breakdancers’ and ‘Ballet’ sequences, respectively, compared recently published results. Moreover, experiments are performed using compressed video from surrounding cameras. The overall system quality is dominated by rendering quality and not by coding.     

Highly enhanced light extraction from organic light emitting diodes with little image blurring and good color stability

We report a highly enhanced light extraction from a top emission organic light emitting diode with little image blurring and color variation with viewing angle. Direct integration of a high refractive index micro lens array on the top of the transparent indium zinc oxide top electrode of a green phosphorescent OLED showed a significant enhancement of light extraction to get EQE of 44.7% from 27.6%, the power efficiency of 134.7 lm/w from 85.9 lm/W and the current efficiency of 217.2 cd/A from 120.7 cd/A without image blurring. In addition, the device showed excellent color stability on viewing angle with Commission Internationale de l’Eclairage (CIE) coordinate of Δx = 0.01, Δy = 0.01 as the viewing angle varied from 0° to 60°.     

A 24-dB Ku-band low-power linearized 90-nm amplifier with a built-in output buffer

In this paper, we present a 90-nm high gain (24 dB) linearized CMOS amplifier suitable for applications requiring high degree of port isolation in the K_u-band (13.2–15.4 GHz). The two-stage design is composed of a low-noise common-gate stage and a gain-boosting cascode block with an integrated output buffer for measurement. Optimization of input stage and load-port buffer parameters improves the front-end's linear coverage, port return-loss, and overall gain without burdening its power demand and noise contribution. With low gate bias voltages (0.65–1.2 V) and an active current source, <?10 dB port reflection loss and 3.25–3.41 dB NF are achieved over the bandwidth. The input reflection loss of the overall amplifier lies between ?35 and ?10 dB and the circuit demonstrates a peak forward gain of 24 dB at 14.2 GHz. The output buffer improves the amplifier's forward gain by ～9 dB and pushes down the minimum output return loss to ?22.5 dB while raising the front-end NF by only 0.05 dB. The effect of layout parasites is considered in detail in the 90-nm process models for accurate RF analysis. Monte Carlo simulation predicts 9% and 8% variation in gain and noise figures resulting from a 10% mismatch in process. The K_u-band amplifier including the buffer block consumes 7.69 mA from a 1.2-V supply. The proposed circuit techniques achieve superior small signal gain, GHz-per-milliwatt, and range of linearity when compared with simulated results of reported microwave amplifiers.     

An automatic region-based video sequence codec based on fractal compression

In order to improve the performance of fractal video coding, we explore a novel fractal video sequences codec with automatic region-based functionality. To increase the quality of decoding image, intra frame coding, deblocking loop filter and sub-pixel block matching are applied to the codec. An efficient searching algorithm is used to increase the compression ratio and encoding speed. Automatic region-based fractal video sequences coding reduces coding stream greatly. Experimental results indicate that the proposed algorithm is more robust, and provides much less encoding time and bitrate while maintaining the quality of decompression image than the conventional CPM/NCIM method and other related references. We compare the proposed algorithm with three algorithms in Refs. [24], [25], [26], and the results of all these four algorithms are compared with H.264. The bitrate of the proposed algorithm is decreased by 0.11% and the other algorithms are increased by 4.29%, 6.85% and 11.62%, respectively. The average PSNR degradations of the four algorithms are 0.71 dB, 0.48 dB, 0.48 dB and 0.75 dB. So the bitrate of the proposed algorithm is decreased and the other algorithms are increased. At the meantime the compression time is reduced greatly, about 79.19% on average. The results indicate that, on average, the proposed automatic region-based fractal video sequences coding system can save compression time 48.97% and bitrate 52.02% with some image quality degradation in comparison with H.264, since they are all above 32 dB and the human eyes are insensitive to the differences.     

White OLED based on a temperature sensitive Eu3+/Tb3+ β-diketonate complex

A mixed lanthanide β-diketonate complex of molecular formula [Eu_0.45Tb_0.55(btfa)₃(4,4′-bpy)(EtOH)] (btfa^– = 4,4,4–trifluoro–1–phenyl–1,3–butanedionate; 4,4′-bpy = 4,4′-dipyridyl; EtOH = ethanol) was synthesized and its structure was elucidated by single crystal X-ray diffraction. The temperature dependence of the complex emission intensity between 11 and 298 K is illustrated by the Commission Internacionale l’Éclairage (CIE) (x, y) color coordinates change within the orange-red region, from (0.521, 0.443) to (0.658, 0.335). The existence of Tb³⁺-to-Eu³⁺ energy transfer was observed at room temperature and as the complex presents a relatively high emission quantum yield (0.34 ± 0.03) it was doped in a 4,4′-bis(carbazol-9-yl)biphenyl (CBP) organic matrix to be used as emitting layer to fabricate a white organic light-emitting diode (WOLED). Continuous electroluminescence emission was obtained varying the applied bias voltage showing a wide emission band from 400 to 700 nm. The white emission results from a combined action between the Eu³⁺ and Tb³⁺ peaks from the mixed Eu³⁺/Tb³⁺ complex and the other organic layers forming the device. The intensity ratio of the peaks is determined by the layer thickness and by the bias voltage applied to the OLED, allowing us to obtain a color tunable light source.     

Multi-symbol QIM video watermarking

This paper introduces the theoretical framework allowing for the binary quantization index modulation (QIM) embedding techniques to be extended towards multiple-symbol QIM (m-QIM, where m stands for the number of symbols on which the mark is encoded prior to its embedding). The underlying detection method is optimized with respect to the minimization of the average error probability, under the hypothesis of white, additive Gaussian behavior for the attacks. This way, for prescribed transparency and robustness constraints, the data payload is increased by a factor of log₂m.m-QIM is experimentally validated under the frameworks of the MEDIEVALS French national project and of the SPY ITEA2 European project, related to MPEG-4 AVC robust and semi-fragile watermarking applications, respectively. The experiments are three-folded and consider the data payload–robustness–transparency tradeoff. In the former case, the main benefit is the increase of data payload by a factor of log₂m while keeping fixed robustness (variations lower than 3% of the bit error rate after additive noise, transcoding and Stirmark random bending attacks) and transparency (set to average PSNR=45 dB and 65 dB for SD and HD encoded content, respectively). The experiments consider 1 h of video content. In the semi-fragile watermarking case, the m-QIM main advantage is a relative gain factor of 0.11 of PSNR for fixed robustness (against transcoding), fragility (to content alteration) and the data payload. The experiments consider 1 h 20 min of video content.     

Improved performance step impedance lowpass filter

Performances of the conventional Butterworth step impedance lowpass filters (LPF) are significantly improved by placing transmission zero either closer to the cut-off frequency (f_c) or away from it. It is achieved by using transverse resonance width of the capacitive line sections. We report method of designing transverse resonance type LPF (TR-LPF) for 5 to 11-pole filters. At f_c = 2.5 GHz, we obtained selectivity in the range 113.3–56.66 dB/GHz and 20–60 dB rejection BW in the range 9.61–7.29 GHz. The TR-LPF can suppress the stopband signal by 60 dB up to 5f_c. Insertion loss in passband is within 0.72 dB. Improved performance of TR-LPF can be designed for f_c up to 7.5 GHz.     

A novel low power UWB cascode SiGe BiCMOS LNA with current reuse and zero-pole cancellation

A low power cascode SiGe BiCMOS low noise amplifier (LNA) with current reuse and zero-pole cancellation is presented for ultra-wideband (UWB) application. The LNA is composed of cascode input stage and common emitter (CE) output stage with dual loop feedbacks. The novel cascode-CE current reuse topology replaces the traditional two stages topology so as to obtain low power consumption. The emitter degenerative inductor in input stage is adopted to achieve good input impedance matching and noise performance. The two poles are introduced by the emitter inductor, which will degrade the gain performance, are cancelled by the dual loop feedbacks of the resistance-inductor (RL) shunt–shunt feedback and resistance-capacitor (RC) series–series feedback in the output stage. Meanwhile, output impedance matching is also achieved. Based on TSMC 0.35 μm SiGe BiCMOS process, the topology and chip layout of the proposed LNA are designed and post-simulated. The LNA achieves the noise figure of 2.3–4.1 dB, gain of 18.9–20.2 dB, gain flatness of ±0.65 dB, input third order intercept point (IIP₃) of ?7 dBm at 6 GHz, exhibits less than 16 ps of group delay variation, good input and output impedances matching, and unconditionally stable over the whole band. The power consumption is only 18 mW.     

Overview of the MVC + D 3D video coding standard

3D video services are emerging in various application domains including cinema, TV broadcasting, Blu-ray discs, streaming and smartphones. A majority of the 3D video content in market is still based on stereo video, which is typically coded with the multiview video coding (MVC) extension of the Advanced Video Coding (H.264/AVC) standard or as frame-compatible stereoscopic video. However, the 3D video technologies face challenges as well as opportunities to support more demanding application scenarios, such as immersive 3D telepresence with numerous views and 3D perception adaptation for heterogeneous 3D devices and/or user preferences. The Multiview Video plus Depth (MVD) format enables depth-image-based rendering (DIBR) of additional viewpoints in the decoding side and hence helps in such advanced application scenarios. This paper reviews the MVC + D standard, which specifies an MVC-compatible MVD coding format.     

A low-voltage low-power CMOS fully differential linear transconductor with mobility reduction compensation

A highly linear fully differential CMOS transconductor architecture based on flipped voltage follower (FVF) is proposed. The linearity of the proposed architecture is improved by mobility reduction compensation technique. The simulated total harmonic distortion (THD) of the proposed transconductor with 0.4V_pp differential input is improved from ?42 dB to ?55 dB while operating from 1.0 V supply. As an example of the applications of the proposed transconductor, a 4th-order 5 MHz Butterworth Gm-C filter is presented. The filter has been designed and simulated in UMC 130 nm CMOS process. It achieves THD of ?53 dB for 0.4V_pp differential input. It consumes 345 μw from 1.0 V single supply. Theoretical and simulated results are in good agreement.     

Low power high gain CMOS LNA based on inverter cell and self-body bias for UWB receivers

A low-power low-noise amplifier (LNA) utilized a resistive inverter configuration feedback amplifier to achieve the broadband input matching purposes. To achieve low power consumption and high gain, the proposed LNA utilizes a current-reused technique and a splitting-load inductive peaking technique of a resistive-feedback inverter for input matching. Two wideband LNAs are implemented by TSMC 0.18 μm CMOS technology. The first LNA operates at 2–6 GHz. The minimum noise figure is 3.6 dB. The amplifier provides a maximum gain (S₂₁) of 18.5 dB while drawing 10.3 mW from a 1.5-V supply. This chip area is 1.028×0.921 mm². The second LNA operates at 3.1–10.6 GHz. By using self-forward body bias, it can reduce supply voltage as well as save bias current. The minimum noise figure is 4.8 dB. The amplifier provides a maximum gain (S₂₁) of 17.8 dB while drawing 9.67 mW from a 1.2-V supply. This chip area is 1.274×0.771 mm².     

Compact circular-patch-based bandpass filter for ultra-wideband wireless communication systems

Ultra-wideband (UWB) is a radio technology that enables low-power-level, short-range, and wide-bandwidth communication, and it has been widely applied in personal area networks, precision geolocation, medical, surveillance, and vehicular radar systems. Since Federal Communications Commission released the unlicensed use of the UWB range (3.1–10.6 GHz), a significant attention has been paid to the development of UWB devices, particularly UWB bandpass filters. In this paper, we propose a novel UWB bandpass filter based on circular patch resonator that is grounded by via and perturbed by slits and defected ground structures. The resonator’s behaviour is analysed in detail and it is shown that its specific configuration allows a flexible control of the three lowest resonant modes, which are used to form UWB passband. To demonstrate the potential of the resonator, a UWB filter has been designed, fabricated, and measured. The filter is characterized by the insertion loss lower than 1 dB and return loss higher than 17 dB within the passband, as well as by very small group delay variation of only 0.07 ns. Also, the filter exhibits suppression higher than 19 dB up to 30 GHz, and very small overall dimensions of only 0.31λ_g × 0.31λ_g, and thus it outperforms other published UWB filters.     

Fast color correction for multi-view video by modeling spatio-temporal variation

In multi-view video, a number of cameras capture the same scene from different viewpoints. Color variations between the camera views may deteriorate the performance of multi-view video coding or virtual view rendering. In this paper, a fast color correction method for multi-view video is proposed by modeling spatio-temporal variation. In the proposed method, multi-view keyframes are defined to establish the spatio-temporal relationships for accurate and fast implementation. For keyframes, accurate color correction is performed based on spatial color discrepancy model that disparity estimation is used to find correspondence points between views, and linear regression is performed on these sets of points to find the optimal correction coefficients. For non-keyframes, fast color correction is performed based on temporal variations model that time-invariant regions are detected to reflect the change trends of correction coefficients. Experimental results show that compared with other methods, the proposed method can promote the correction speed greatly without noticeable quality degradation, and obtain higher coding performance.     

STI-to-gate distance effects on flicker noise characteristics in 0.13 μm CMOS

The geometry effect on the flicker noise characteristics and the variations in 0.13 μm CMOS transistors were studied. By symmetrically extending the distance between the shallow-trench-isolation (STI) to the gate, both NMOS and PMOS presented obvious improvement on the noise characteristics. As the distance increased from 0.6 μm to 10 μm, the average noise level reduced by more than one order of magnitude (NMOS) and the standard deviations σ_dB improved from 5.95 dB to 1.79 dB for NMOS and from 3.93 dB to 2.17 dB for PMOS, respectively. To further identify the noise mechanism, the devices with asymmetrical STI-to-gate distances were also investigated. It was found that the distance in the source side (SA) has a much higher impact on the observed noise characteristics. The results suggested that the noise characteristics were dominated by the STI stress induced traps for both NMOS and PMOS studied here. In addition, the carrier number fluctuation model with the correlated mobility scattering could be more suitable to describe the noise characteristics in these devices.     

Spiro-fused N-phenylcarbazole-based host materials for blue phosphorescent organic light-emitting diodes

Two host materials, SFCA and SFCC, consist of a diphenylamine or carbazole unit linking to spiro-fused phenyl carbazole (SFC) backbone, were designed and synthesized. By choosing the meta linkage way between diphenylamine/carbazole units and SFC ring, higher triplet energies could be easily achieved for the two new materials, which mean that they could be used as effective host material for popular blue phosphorescent material Iridium(III) bis[(4,6-difluorophenyl)pyridinato-N,C^2′] picolinate (FIrpic, E_T = 2.65). Besides that, the steric SFC structure could guarantee their good thermal stabilities. Their thermal, photophysical and electroluminescent properties were systematically investigated. The blue phosphorescent OLEDs with the two materials as hosts and FIrpic as a dopant exhibited excellent performance with maximum current efficiencies of 33.9 and 40.8 cd/A, respectively.     

Dictionary learning based reconstruction for distributed compressed video sensing

Distributed compressed video sensing (DCVS) is a framework that integrates both compressed sensing and distributed video coding characteristics to achieve a low-complexity video coding. However, how to design an efficient reconstruction by leveraging more realistic signal models that go beyond simple sparsity is still an open challenge. In this paper, we propose a novel “undersampled” correlation noise model to describe compressively sampled video signals, and present a maximum-likelihood dictionary learning based reconstruction algorithm for DCVS, in which both the correlation and sparsity constraints are included in a new probabilistic model. Moreover, the signal recovery in our algorithm is performed during the process of dictionary learning, instead of being employed as an independent task. Experimental results show that our proposal compares favorably with other existing methods, with 0.1–3.5 dB improvements in the average PSNR, and a 2–9 dB gain for non-key frames when key frames are subsampled at an increased rate.     

A broadband and compact asymmetrical backward coupled-line coupler with high coupling level

A new wideband asymmetric microstrip coupled-line coupler with 3 dB coupling value and quadrature phase difference is presented. Compared with the conventional edge-coupled couplers, this structure, consisting of two different transmission lines (interdigital and conventional microstrip transmission lines) as coupled lines, achieves wider operating bandwidth and larger coupling level. The coupled-line length of the proposed structure is approximately λ_g/4. To characterize the structure, an equivalent circuit model has been established. A 3 dB designed and fabricated coupler with 0.2 mm spacing between coupled lines exhibits an amplitude balance of 2 dB from 2.2 GHz to 4.2 GHz. Good agreements between the full-wave simulation and equivalent circuit model results has been achieved and verified the effectiveness of the proposed circuit model. Also, measurement results have been presented.     

Single-grain Si thin-film transistors SPICE model,analog and RF circuit applications

Single-grain thin-film transistors (SG-TFTs) fabricated inside location-controlled using μ-Czochralski process exhibit SOI-FETs like performance despite processing temperatures remaining below 350 °C. Thus, the SG-TFT is a potential technology for large-area highly-integrated electronic system and system-in-package, taking advantage of the system-on-flexible substrate and low manufacturing cost capabalities. The SG-TFT is modeled based on the BSIMSOI SPICE model where the mobility parameter is modified to fit the SG-TFT behavior. Therefore, analog and RF circuits can be designed and benchmarked. A two-stage telescopic cascode operational amplifier fabricated in a prototype 1.5 μm SG-TFT technology demonstrates DC gain of 55 dB and unity-gain bandwidth of 6.3 MHz. A prototype CMOS voltage reference demonstrates a power supply rejection ratio (PSRR) of 50 dB. With unity-gain frequency, f_T, in the GHz range, the SG-TFT can also enable RF circuits for wireless applications. A 12 dB gain RF cascode amplifier with integrated on-chip inductors operating in the 433 MHz ISM band is demonstrated.     

Coding-oriented multi-view video color correction

Color inconsistency between views is an important problem to be solved in multi-view video applications, such as free viewpoint television and other three-dimensional video systems. In this paper, by combining with multi-view video coding, a coding-oriented multi-view video color correction method is proposed. We first separate foreground and background in first Group Of Pictures （GOP） by using SKIP coding mode. Then by transferring means and standard deviations in backgrounds, color correction is performed for each frame in GOP, and multi-view video coding is performed and used to renew the backgrounds. Experimental results ances in color correction and multi-view video show the proposed method can obtain better performcoding.     

A UWB CMOS low-noise amplifier with noise reduction and linearity improvement techniques

In this paper, a highly linear CMOS low noise amplifier (LNA) for ultra-wideband applications is presented. The proposed LNA improves both input second- and third-order intercept points (IIP2 and IIP3) by canceling the common-mode part of all intermodulation components from the output current. The proposed LNA structure creates equal common-mode currents with the opposite sign by cascading two differential pairs with a cross-connected output. These currents eliminate each other at the output and improve the linearity. Also, the proposed LNA improves the noise performance by canceling the thermal noise of the input and auxiliary transistors at the output. Detailed analysis is provided to show the effectiveness of the proposed LNA structure. Post-layout circuit level simulation results using a 90 nm RF CMOS process with Spectre-RF reveal 9.5 dB power gain, -3 dB bandwidth (BW_−3dB) of 8 GHz from 2.4 GHz to 10.4 GHz, and mean IIP3 and IIP2 of +13.1 dBm and +42.8 dBm, respectively. The simulated S₁₁ is less than −11 dB in whole frequency range while the LNA consumes 14.8 mW from a single 1.2 V power supply.