• KIPS Transactions on Software and Data Engineering
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• v.6 no.1
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• pp.15-22
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• 2017

With the advance of Internet Technology, various social network services are created and used by users. Especially, the use of smart devices makes that multimedia contents can be used and distributed on social network services. However, since the crime rate also is increased by users with illegal purposes, there are needs to protect contents and block illegal usage of contents with multimedia forensics. In this paper, we propose a multimedia forensic technique which is identifying the video source. First, the scheme to acquire the sensor pattern noise (SPN) using morphology filtering is presented, which comes from the imperfection of photon detector. Using this scheme, the SPN of reference videos from the reference device is estimated and the SPN of an unknown video is estimated. Then, the similarity between two SPNs is measured to identify whether the unknown video is acquired using the reference device. For the performance analysis of the proposed technique, 30 devices including DSLR camera, compact camera, camcorder, action cam and smart phone are tested and quantitatively analyzed. Based on the results, the proposed technique can achieve the 96% accuracy in identification.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.642-649
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• 2016

This study examined the meaning of instructional materials by observing the daily work of an infant class in a daycare center to make some suggestions on the accreditation and evaluation of instructional materials for early childhood education and educare. Ethnography was chosen to determine in detail what the instructional materials meant for the selected preschoolers. The activities that belonged to each area of free optional activities and made use of instructional materials were observed, and the eating time, nap time, and outdoor play were all observed. The data were gathered by visiting the selected daycare center. A participant observation and teacher interviews were conducted, and notes were taken on the spot. When their verbal expressions and nonverbal expressions needed to be observed owing to their unique characteristics, a camcorder was used to record their words to have a more profound understanding of them. All the collected data that included this researcher's observation note, the teacher interview data, the standard childcare curriculum manual, the daycare center's yearly, and the daily childcare plans and curriculum evaluation data were classified and categorized by performing an inductive analysis. As a result, the instructional materials had three meanings for the infants. The first was "friends who welcomed them and whom they could play with.' The second was "a cozy nest," and the third was "another teacher." Given the findings of the study, the preparation of standards for instructional materials for infants in childcare facilities is required, and even equipment that is used as instructional materials should be taken into consideration when instructional materials for infants are accredited.