• Journal of The Korean Ophthalmological Society
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• v.58 no.11
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• pp.1313-1316
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• 2017

Purpose: To report fundus photography using a smartphone in an infant with abusive head trauma. Case summary: An 8-month-old male infant presented to the emergency room with decreased consciousness and epileptic seizures that the parents attributed to a fall from a chair. He had no external wounds or fractures to the skull or elsewhere. However, computerized tomography of the brain revealed an acute subdural hematoma in the right cranial convexity and diffuse cerebral edema, leading to a midline shift to the left and effacement of the right lateral ventricle and basal cistern. The attending neurosurgeon promptly administered a decompressive craniectomy. Immediately after the emergency surgery, a fundus examination revealed numerous multi-layered retinal hemorrhages in the posterior pole extending to the periphery in each eye. He also had white retinal ridges with cherry hemorrhages in both eyes. We acquired retinal photographs using the native camera of a smartphone in video mode. The photographer held the smartphone with one hand, facing the patient's eye at 15-20 cm, and held a 20 diopter condensing lens at 5 cm from the eye in the other hand. Our documentation using a smartphone led to a diagnosis of abusive head trauma and to obtain the criminal's confession, because the findings were specific for repetitive acceleration-deceleration forces to an infant's eye with a strong vitreoretinal attachment. Conclusions: This ophthalmic finding had a key role in the diagnosis of abusive head trauma. This case presented the diagnostic use of a smartphone for fundus photography in this important medicolegal case.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.2
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• pp.98-102
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• 2013

There are so many CCTV in our streets, buildings and public places. Nevertheless, security methods for CCTV are rarely. This paper describes a study on developing a media crypto algorithm for anti-hacking into CCTV. H.264 codec is used to compress the video stream in CCTV systems. HIGHT algorithm provided by KISA is adopted as a crypto algorithm in our development. Other crypto methods except HIGHT could be selected by company's security police. Only some bytes in VCL(Video Coding Layer) of H.264 are encrypted to improve the performance of limited platforms, such as CCTV, WebCam, smartphone. Very fast and light crypto algorithm was developed by our researches.

• International journal of advanced smart convergence
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• v.10 no.4
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• pp.273-277
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• 2021

As society gradually enters a virtual, non-face-to-face society, the use of online content is increasing as well. In particular, as smartphones are thoroughly established in our daily life, the platforms of webtoons, mobile broadcasting, and education are shifting from personal computers to smartphones. Recently, the development of the Over-The-Top media service (OTT service) enabled streaming services of various media contents through the internet and activation of IPTV. Therefore, the rapid increase of popularity of short-form content is a natural phenomenon with smartphone platforms with fast, improvised, and endless communication. Lately, TikTok became the favored platform with prosumers, defined as people who are both producers and consumers. In this study, I studied the experiential response of YouTube and TikTok users as representative examples of a short-form content platform developed after the 2000s, the flourishing years of digital content with a length of 30 seconds.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.25 no.4
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• pp.327-336
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• 2021

In this paper, we will introduce the image processing methods for the remote pupillary light reflex measurement using the video taken by a general smartphone camera without a special device such as an infrared camera. We propose an algorithm for estimate the size of the pupil that changes with light using image data analysis without a learning process. In addition, we will introduce the results of visualizing the change in the pupil size by removing noise from the recorded data of the pupil size measured for each frame of the video. We expect that this study will contribute to the construction of an objective indicator for remote pupillary light reflex measurement in the situation where non-face-to-face communication has become common due to COVID-19 and the demand for remote diagnosis is increasing.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.11
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• pp.1546-1549
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• 2020

This paper introduces the development process of mobile home CCTV that enables remote control and object recognition using unused smartphones and Arduino. Clients can control motors connected to Arduino through button, enable bidirectional voice communication between client-server and receive video from the server in real time. The server sends a PUSH notification to the client when its battery is low. When the server recognizes the charger, the client's remote control allows the server to dock to the charger and charge it. It was confirmed that video and voice delivery between client and server works well without any problems, and that object recognition works smoothly.

• KIISE Transactions on Computing Practices
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• v.20 no.11
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• pp.604-609
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• 2014

Decoding processes in portable media players have a high computational cost, resulting in high power consumption by the CPU. If decoding computations are reduced, the power consumed by the CPU is also be reduced, but such a choice generally results in a degradation of the video quality for the users, so it is essential to address this tradeoff. We proposed a new CPU power management scheme that can make use of the scalability property available in the H.164/SVC standard. We first proposed a new video quality model that makes use of a video quality metric(VQM) in order to efficiently take into account the different quantization factors in the SVC. We then propose a new dynamic voltage scaling(DVS) scheme that can selectively combine the previous decoding times and frame sizes in order to accurately predict the next decoding time. We then implemented a scheme on a commercial smartphone and performed a user test in order to examine how users react to the VQM difference. Real measurements show that the proposed scheme uses up to 34% fewer energy than the Linux DVFS governor, and user tests confirm that the degradation in the quality is quite tolerable.

• Physical Therapy Rehabilitation Science
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• v.11 no.4
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• pp.454-463
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• 2022

Objective: The purpose of this study was to compare concurrent validity and test-retest reliability based on Craniovertebral angle of 'Angles video goniometer', a smart phone application for convenient range of motion measurement, and 'Image J', an analysis software with high reliability and validity. This was conducted to find out whether 'Angle video goniometer' can be used clinically. Design: Cross-sectional study Methods: Fifty subjects were imaged laterally, and the angle of the head and spine was measured using Image J and the Angles video goniometer, respectively, in a resting posture and a chin in posture. The level of concurrent validity between the two measurement methods and the level of inter-rater reliability and intra-rater reliability were analyzed. Results: For forty participants, the concurrent validity between Image J and Angles video goniometer showed very high validity with ICC of 0.997(0.995~0.999) and 0.994(0.994~0.998), CVME% 0.71~0.72%, SEM% 0.31~0.34, MDC% 0.86~0.94. The test-retest intra-rater reliability showed very high reliability ICC 0.994(0.991~0.996), CVME% 0.71%, SEM% 0.31~0.43, MDC% 0.86~1.19%. The test-retest inter-rater showed very high reliability ICC 0.995(0.992~0.997), CVME% 0.71%, SEM% 0.43~0.59%, MDC% 1.20~1.62% Conclusions: Angles video goniometer', a smartphone application, is a device with very high reliability and validity for craniovertebral angle measurement in healthy adults, and it is a device that can be easily used in clinical practice.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.250-253
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• 2016

Car black box is saved in the video recording important to determine the cause of the accident caused a traffic accident occurred. Remote monitoring of the current black box may be monitored or transmitted to shock your smartphone as a yourself. It complements if the parties to an accident lost per injury due to an accident or mind when responding to spend the "INVITE" message using the SIP visual communication in messanger applications "Notify" to inform transferring video to a message acquaintances to check Video the accident to identify the location and check the contents and to implement and research that can respond quickly.

• ETRI Journal
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• v.44 no.1
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• pp.62-72
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• 2022

In this study, we propose a multi-GPU-based 8KVR stitching system that operates in real time on both local and cloud machine environments. The proposed system first obtains multiple 4 K video inputs, decodes them, and generates a stitched 8KVR video stream in real time. The generated 8KVR video stream can be downloaded and rendered omnidirectionally in player apps on smartphones, tablets, and head-mounted displays. To speed up processing, we adopt group-of-pictures-based distributed decoding/encoding and buffering with the NV12 format, along with multi-GPU-based parallel processing. Furthermore, we develop several algorithms such as equirectangular projection-based color correction, real-time CG overlay, and object motion-based seam estimation and correction, to improve the stitching quality. From experiments in both local and cloud machine environments, we confirm the feasibility of the proposed 8KVR stitching system with stitching speed of up to 83.7 fps for six-channel and 62.7 fps for eight-channel inputs. In addition, in an 8KVR live streaming test on the 5G MEC/cloud, the proposed system achieves stable performances with 8 K@30 fps in both indoor and outdoor environments, even during motion.

• Journal of Korea Game Society
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• v.17 no.6
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• pp.19-28
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• 2017

There exist a variety of VR(Virtual Reality) contents that have been developed by the use of the latest VR technologies. Unlike the rapid advances in the recent VR devices however, the development of VR based game contents that fully utilize such cutting-edge devices has been lackluster. Using more accessible form of smartphone-based HMDs(Head-Mounted Displays), we compare two popular VR presentation methods(a realistic 3D VR karaoke room and a 360 degree video karaoke room) and analyze their users' immersion and realistic perception. We expect that our study can be utilized as a supporting guideline for future smartphone-based VR content developments.