• ETRI Journal
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• v.28 no.6
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• pp.721-731
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• 2006

A fast intra skip detection algorithm based on the ratedistortion (RD) cost for an inter frame (P-slices) is proposed for H.264/AVC video encoding. In the H.264/AVC coding standard, a robust rate-distortion optimization technique is used to select the best coding mode and reference frame for each macroblock (MB). There are three types of intra predictions according to profiles. These are $16{\times}16$ and $4{\times}4$ intra predictions for luminance and an $8{\times}8$ intra prediction for chroma. For the high profile, an $8{\times}8$ intra prediction has been added for luminance. The $4{\times}4$ prediction mode has 9 prediction directions with 4 directions for $16{\times}16$ and $8{\times}8$ luma, and $8{\times}8$ chrominance. In addition to the inter mode search procedure, an intra mode search causes a significant increase in the complexity and computational load for an inter frame. To reduce the computational load of the intra mode search at the inter frame, the RD costs of the neighborhood MBs for the current MB are used and we propose an adaptive thresholding scheme for the intra skip extraction. We verified the performance of the proposed scheme through comparative analysis of experimental results using joint model reference software. The overall encoding time was reduced up to 32% for the IPPP sequence type and 35% for the IBBPBBP sequence type.

• The Journal of the Acoustical Society of Korea
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• v.24 no.8
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• pp.462-468
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• 2005

In this paper, we present a frame synchronization scheme for high oversampling rate based QPSK receiver system in the underwater acoustic burst transmission. The proposed frame synchronization scheme determines the frame synchronization by comparing a threshold value with the correlation between the received symbol sequence and rotated 16-symbol length CAZAC sequence, which is made by dividing into two 8-symbol length sequences and then concatenating the latter sequence and the former one. If the correlation value is bigger than the threshold value, the frame detector determines that the frame synchronization is achieved at that sample. Also, the approximated performance of designed frame detector is derived and it is well fit the simulated result.

• International Journal of Contents
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• v.8 no.1
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• pp.16-22
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• 2012

In this paper we propose a method for verifying video in a video telephony system implemented in DM6446 DaVinci Processor. Each frame is categorized either error free frame or error frame depending on the predefined criteria. Human face is chosen as a basic means for authenticating the video frame. Skin color based algorithm is implemented for detecting the face in the video frame. The video frame is classified as error free frame if there is single face object with clear view of facial features (eyes, nose, mouth etc.) and the background of the image frame is not different then the predefined background, otherwise it will be classified as error frame. We also implemented the image histogram based NCC (Normalized Cross Correlation) comparison for video verification to speed up the system. The experimental result shows that the system is able to classify frames with 90.83% of accuracy.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.1
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• pp.8-16
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• 2014

We consider the visual barcode recognition problem in a noisy video data setup. Unlike most existing single-frame recognizers that require considerable user effort to acquire clean, motionless and blur-free barcode signals, we eliminate such extra human efforts by proposing a robust video-based barcode recognition algorithm. We deal with a sequence of noisy blurred barcode image frames by posing it as an online filtering problem. In the proposed dynamic recognition model, at each frame we infer the blur level of the frame as well as the digit class label. In contrast to a frame-by-frame based approach with heuristic majority voting scheme, the class labels and frame-wise noise levels are propagated along the frame sequences in our model, and hence we exploit all cues from noisy frames that are potentially useful for predicting the barcode label in a probabilistically reasonable sense. We also suggest a visual barcode tracking approach that efficiently localizes barcode areas in video frames. The effectiveness of the proposed approaches is demonstrated empirically on both synthetic and real data setup.

• Journal of the Ergonomics Society of Korea
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• v.33 no.6
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• pp.499-513
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• 2014

Objective: The objective of this study was to examine frame ratio of text information and font size in the circle smartwatch. Background: Recently, electronic manufacturers try to develop the original metaphor of traditional wrist watch (circle) in terms of smartwatch. They endeavor to break the square display in order to improve emotional customer satisfaction. Method: The experiments examined twenty level of text information design, combinations of four frame ratios (1:1, 4:3, 16:9, 21:9) and five font sizes (6pt, 7pt, 8pt, 9pt, 10pt). Nineteen participants volunteered for the experiment. Dependent variables were WPM (Words per Minute), reading preference, design preference and total preference. Furthermore, small circle display was made by using circle display data (1.3inch), which was exhibited in IFA (International Funkausstellung) 2014. Results: As a result, ANOVA (Analysis of Variance) revealed that WPM, and task time preference affect the specific frame ratio and font size. Results of ANOVA for reading preference, design preference, total preference were grouped by post-analysis LSD (Least Significant Difference). Among users, display ratio (16:9, 21:9), and font size (9pt) were preferred. In conclusion, 16:9 display ratio and 9pt are adaptable for text information in 1.3inch circle display. Conclusion: From the study, it is shown that 16:9 display ratio and 9pt size are more adaptable for text information in 1.3inch circle display than others. It is mainly due to the fact that the order of frame ratio and font size may affect the usability of reading long text information in a small circle display. Therefore, when developers design a circle display, the square frame ratio and font size are required to be considered according to circle size. Application: The 16:9 display ratio and 9pt font size may be utilized as a text information frame in the circle display design guideline for smartwatch.

• Journal of Digital Contents Society
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• v.7 no.3
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• pp.169-174
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• 2006

In recent years, RFID is widely used in industrial applications including factory, material flow, logistics and defense areas. In this paper, The convolutional encoding and viterbi decoding is also implemented to improve the system performance. in an FPGA chip. The used convolution code is constraint length K=3 and rate R=1/2. The length of command frame and response frame is total of 48bits consisting of SOF 8 bits, command 16 bits, CRC 16 bit, and EOF 8 bits. And also the frame error rates are measured under the channel of line-of-sight and non line-of-sight, respectively. The performances are analyzed with FSK modulation only and FSK modulation added with convolutional encoding. These two measured results are compared with that of a RFID system with ASK modulation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.8
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• pp.1631-1641
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• 2012

A TDMA system in satellite communication has been utilized. Especially DVB-S2 was standardized and now operated in satellite broadcasting system. In this paper, we propose a TDMA frame structure appropriate for special purpose which has the good reliablilty in a poor RF environment even if frequency efficiency is decreased. TDMA frame duration is 12 seconds which is long duration in comparison with general TDMA system with several ms. Designing the frame structure, time and frequency shift in single frame duration are considered. Simulation results show that the proposed frame structure and synchronization method has robust synchronization performance when the terminal is even in low SNR as well as 25 kHz frequency offsets.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.11
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• pp.4589-4592
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• 2015

Background: Missense and frame-shift mutations within the dimer forming domain of the caspase 8 gene have been identified in several cancers. However, the genetic status of this region in precancerous lesions, like oral submucous fibrosis (OSMF), and well differentiated oral squamous cell carcinomas (OSCCs) in patients from southern region of India is not known, and hence the present study was designed to address this issue. Materials and Methods: Genomic DNA isolated from biopsy tissues of thirty one oral submucous fibrosis and twenty five OSCC samples were subjected to PCR amplification with intronic primers flanking exon 7 of the caspase 8 gene. The PCR amplicons were subsequently subjected to direct sequencing to elucidate the status of mutation. Results: Sequence analysis identified a frame-shift and a novel missense mutation in two out of twenty five OSCC samples. The frame-shift mutation was due to a two base pair deletion (c.1225_1226delTG), while the missense mutation was due to substitution of wild type cysteine residue with phenylalanine at codon 426 (C426F). The missense mutation, however, was found to be heterozygous as the wild type C426C codon was also present. None of the OSMF samples carried mutations. Conclusions: The identification of mutations in OSCC lesions but not OSMF suggests that dimer forming domain mutations in caspase 8 may be limited to malignant lesions. The absence of mutations in OSMF also suggests that the samples analyzed in the present study may not have acquired transforming potential. To the best of our knowledge this is the first study to have explored and identified frame-shift and novel missense mutations in OSCC tissue samples.

• Journal of Web Engineering
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• v.20 no.8
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• pp.2413-2432
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• 2021

Recently, the demand for high-quality video content has rapidly been increasing, led by the development of network technology and the growth in video streaming platforms. In particular, displays with a high refresh rate, such as 120 Hz, have become popular. However, the visual quality is only enhanced if the video stream is produced at the same high frame rate. For the high quality, conventional videos with a low frame rate should be converted into a high frame rate in real time. This paper introduces a bidirectional intermediate flow estimation method for real-time video frame interpolation. A bidirectional intermediate optical flow is directly estimated to predict an accurate intermediate frame. For real-time processing, multiple frames are interpolated with a single intermediate optical flow and parts of the network are implemented in 16-bit floating-point precision. Perceptual loss is also applied to improve the cognitive performance of the interpolated frames. The experimental results showed a high prediction accuracy of 35.54 dB on the Vimeo90K triplet benchmark dataset. The interpolation speed of 84 fps was achieved for 480p resolution.

• Steel and Composite Structures
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• v.16 no.1
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• pp.1-21
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• 2014

Knee Braced Frame (KBF) is a special form of ductile eccentrically braced frame having a diagonal brace connected to a knee element, as a hysteretic damper, instead of beam-column joint. This paper first presents an experimental investigation on cyclic performance of two knee braced single span one-story frame specimens. The general test arrangement, specimen details, and most relevant results (failure modes and hysteretic curves) are explained. Some indexes to assess the seismic performance of KBFs, including ductility; response reduction factor and energy dissipation capabilities are also subsequently discussed. Experimental results indicate that the maximum equivalent damping ratios achieved by test frames are 21.8 and 23% for the specimens, prior to failure. Finally, a simplified analytical model is derived to predict the bilinear behavior of the KBFs. Acceptable conformity between analytical and experimental results proves the accuracy of the proposed model.