Blurred Edge Width Research Articles

Maneuvering Trajectory Synthetic Aperture Radar Processing Based on the Decomposition of Transfer Functions in the Frequency Domain Using Average Blurred Edge Width Assessment

With the rapid development of synthetic aperture radar (SAR), delivery platforms are gradually becoming diversified and miniaturized. The SAR flight process is susceptible to external influences, resulting in unsatisfactory imaging results, so it is necessary to optimize imaging processing in combination with the SAR imaging quality assessment (IQA) index. Based on the principle of SAR imaging, this paper analyzes the impact of defocusing on imaging results caused by mismatched filters and draws on the assessment algorithm of motion blur, proposing a SAR IQA index based on average blurred edge width (ABEW) in the salient area. In addition, the idea of decomposing the transfer function in the frequency domain and fitting the matched filter with a polynomial is also proposed. The estimation of the flight trajectory is changed to a correction of the matched filter, avoiding the precise estimation of Doppler parameters and complex calculations during the time–frequency conversion process. The effectiveness of ABEW was verified by using SAR images of real scenes, and the results were highly consistent with the actual image quality. The imaging processing was tested using the echo signals generated by the errors introduced during the flight process, and more satisfactory imaging results were obtained by using ABEW with the filter for correction. The imaging process was tested using the echo signal generated by introducing errors during the flight, and the filter was corrected using ABEW as an index, obtaining a comparatively ideal imaging result.

Effect of 3D depth on the resolution and the observed image for auto‐stereoscopic multi‐view 3D display

AbstractIn auto‐stereoscopic multi‐views, blurring occurs due to the incomplete separation of views for non‐zero depths. How this blur affects a 3D image was investigated using the commercial multi‐view 3D. The 3D input signal consisted of the square pattern and the gratings of various width and gray level values of G1 and G2. The various combinations of G1 and G2 were used to investigate the dependence of blur on gray G1 and G2 values. The 3D depth caused blurring, which caused a decrease in contrast modulation. Hence, the 3D resolution determined from contrast modulation was affected by the depth and became worse with increasing depth. Therefore, 3D resolution may be used to define the depth range within which the image degradation due to blurring is acceptable. Blur edge width values at the boundaries of gray G1 and G2 were measured and found to be similar irrespective of G1 and G2 values at the same depth. This was because blur was caused by the incomplete separation of views that are independent of G1 and G2. Hence, the blurriness of the observed 3D image is determined only by the depth. The 3D resolution and blur edge width might be useful to characterize the performance of auto‐stereoscopic multi‐view 3D.

Influence of depth and 3D crosstalk on blur in multi‐view 3D displays

AbstractCurrent 3D crosstalk equation was defined from the characteristics of 3D display using glasses. This equation is not suitable for multi‐view 3D display with larger view number as it gives the inappropriately large value. In 3D display using eyeglass, double images occur at large depth. But, in multi‐view 3D display with larger view number, blur occurs to larger width for the larger depth. Hence, blur phenomenon of multi‐view 3D display was investigated to understand the unique characteristics of multi‐view 3D display. For this purpose, ray tracing S/W was used to simulate 3D display image seen at the designed viewing distance, to calculate the relative luminance distribution, and to quantify the relation between blur and depth. Calculated results showed that incomplete image separation caused the overlap of multiple view images and the blur. Blur edge width (BEW) was proportional to the horizontal disparity and related to the depth. BEWR = (BEW) / (binocular disparity) was newly defined, and its usefulness for 3D characterization was investigated. BEW and BEWR might be useful as new measuring items to characterize multi‐view 3D display regarding 3D crosstalk.

OLED 디스플레이의 전력 저감 및 모션 블러 개선에 관한 연구

In this paper, we proposed a new driving scheme to reduce the motion blur and save the power for OLEDs(organic light emitting diodes). We adopted a DVS (dynamic voltage scaling) method to reduce power consumption and the division of TV field to improve motion blur. In the proposed scheme, BEW (Blur Edge Width) was decreased to the ratio of 1/4 compared to the conventional scheme under the optimal conditions. In this scheme, the gray levels to which the DVS method can be applied were divided into much smaller groups depending on the number of subfields. Therefore, our scheme does not guarantee less power consumption for every image compared to the conventional scheme. However, the new scheme can move the gray levels adopting the DVS to higher gray levels. Thus, we can save power even when having images at high gray levels.

An Automatic Focusing Algorithm Based on Blur Edge Width Detection in the Image

An automatic focusing algorithm through detecting blur edge width via wavelet transform was proposed. To improve computation speed and fit for different scenes, the center area of the image and four golden points were selected as the focusing area. Wavelet module values of the focusing area were obtained through wavelet transform. The threshold to determine blur edge was selected by 50 percent of the wavelet module maximum in all wavelet module values. According to the threshold, the binary image of the blur edge was achieved. Area and girth of the blur edge were calculated respectively, and blur edge width was computed by area and girth. The control center computed steps according to blur edge width to adjust the lens, and the focusing motor operated corresponding steps received from the control center. Therefore, an automatic focusing procedure was implemented. Results show that the automatic focusing algorithm is quick and effective.

Improved measurement of dynamic modulation transfer functions on display using pursuit camera method based on wavelet-denoising method

A new method was developed for studying dynamic modulation transfer functions (DMTFs) of liquid crystal display (LCD) based on the slanted edge method, improved wavelet-denoise (IWD) method, and Fourier transformation. Measurements were made for capturing the images of moving step-edge patterns on the display by a slightly tilted pursuit camera. The scanning-rate and contrast-dependent DMTFs of a LCD were demonstrated, and the corresponding parameters such as blurred edge width (BEW), spatial sharpness, and motion picture response time (MPRT) were calculated from the DMTF curves. A simple linear relationship between these parameters was found. The properties of a cathode ray tube (CRT) display were also measured for comparison with those of the LCD.

61.3: Visual Annoyance and User Acceptance of LCD Motion‐Blur

AbstractIt has been recognized for some time now that LCD displays will introduce blur when showing moving objects or moving images. Common motion‐blur measurement methods permit to picture the blurred profile of an edge moving with a constant velocity. A normalized blurred edge width is then measured for several gray‐to‐gray transitions to give a motion‐blur score of the display under test. However, these objective measurements are partly based on the behavior of the human visual system and it is an open question how well they correlate with subjective experience of observers. In this study, we develop a subjective experiment in order to assess the annoyance and the acceptance of motion‐blur. Results are given and compare with measurements data.

Motion‐blur characterization on liquid‐crystal displays

Abstract— In this paper, several methods to characterize motion blur on liquid‐crystal displays are reviewed. Based on the assumptions of smooth‐pursuit eye tracking and one‐frame temporal luminance integration, a simple algorithm has been proposed to calculate the normalized blurred edge width (N‐BEW) and motion‐picture response time (MPRT) with a one‐frame‐time moving‐window function to LC temporal step response curves. A custom measurement system with a fast‐eye‐sensitivity‐compensated photodiode has been developed to characterize motion blur based on LC response curves (LCRCs). MPRT values obtained by using the algorithm mentioned above and those from the smooth‐pursuit‐camera methods agree. Perception experiments were conducted to validate the correspondence between the simulated results and actual perceived images by the human eyes. In addition, the insufficiency of MPRT to evaluate motion blur on impulse‐type light‐generation LCDs, by analyzing the measurement results of a scanning backlight LCD, is discussed.

P‐40: Color Bias Elimination Technique for Motion Image

AbstractThe issue of the color motion blur had become the most significant study of the LCD image quality. The motion blur edge width and the motion color bias are two major components of the color motion blur. In this paper, a color bias elimination technique was proposed to improve the image quality of motion color images. The added pseudo color was presented to reduce the level of color bias and new color bias index was used to judge the level of color bias of captured images via a pursuit camera system. The color lookup table (CLUT) had built automatically by this technique to improve the image quality of moving color images. Experiment results revealed that the added pseudo color images had the better image quality than the original moving images not only in the color bias index evaluation but also in the subjective test.

ディスプレイ―ＩＤＷ’０７を中心に―視覚特性を考慮したディスプレイの動きぼやけ評価法に関する一考察

We examined the validity of perceived blur edge width (PBEW) by analyzing the correlation between observer rating values and physical properties that were extended blur edge width (EBEW) and PBEW. We also examined the correlation with changing contrast sensitivity function (CSF) models in the calculation of PBEW. In our results, PBEW correlated more with the observer's rating values than EBEW. It was also shown that Spatio-Velocity CSF model is significant for calculating PBEW.

P-25: Acceptable Motion Blur Levels of a LCD TV Based on Human Visual System

Visual perception experiments were conducted to determine the limits of motion blur at moving pictures. The results showed that the Blurred Edge Width(BEW) of moving pictures should be below 3.4pixels (visual angle 4.2′) at 3H distance in a living room environment.

3.3: Edge Blur Width Analysis Using a Contrast Sensitivity Function

Motion blur edge width is obtained by using a contrast sensitivity function of eye. Correlation with an eye perceived blur edge width is improved. The improvement is large in the case of abnormal transition. We set a standard analysis condition of 8 deg/s velocity and 3H viewing distance. Measured blur widths are compared with a subjective test. This study is done to establish IEC standard method.

Guiding principles for high-quality moving picture in LCD TVs

— The moving-picture quality of several LCD modules was evaluated by using the quantitative parameter, normalized blurred edge width (N-BEW), or the N-BEW value normalized by time (N-BET), measured and calculated by the developed time-sequence-image integration system which has taken LCD-response characteristics and human-vision characteristics into consideration. The quality of several LCD TVs is also discussed by using subjective evaluation and the unified quantitative parameter moving-picture response time (MPRT), which is based on N-BEW. According to the experimental and calculated results, it is clear that the value of N-BET can express moving-picture quality, which depends on the liquid-crystal response time and the hold-type character of LCDs. Also, it is confirmed that the value of MPRT can express the moving-picture quality by comparison with subjective evaluation. The target values of MPRT and N-BET for the motion-blur-less picture are deduced by extrapolating the subjective evaluation results. Then, guidelines to improve the moving picture quality are demonstrated.

54.2: LCD Motion Blur Analysis and Modeling Based on Temporal PSF

In this paper, an LCD motion blur model using CRT as a reference is discussed. This model, covering both LCD and HVS characteristics, shows that the temporal point spread function (temporal PSF) of an LCD device determines its motion blur, and the normalized blurred edge width (N-BREW) in MPRT describes the effective width of temporal PSFs, while response time (RT) describes the rising edge of the temporal PSF of fast hold-type LCDs. We also theoretically derive the temporal PSFs of many old and new LCD temporal rendering technologies in this paper. Finally, this model is verified by a subjective experiment.