Multi Video Research Articles

Multi video summarization using query based deep optimization algorithm

Multi video summarization using query based deep optimization algorithm

ANALYSIS OF GULLY EROSION IN A CATCHMENT AREA IN OLIVE GROVES USING UAS PHOTOGRAMMETRY TECHNIQUES

Abstract. An approach based on images captured by means of an Unmanned Aerial System (UAS) and Structure from Motion – Multi Video Stereo (SfM-MVS) photogrammetry is presented for the study of the gully erosion in a catchment area of about 16 ha. The study area is located in the province of Jaén (SW Spain) where the main land use is the olive groves. Three UAS flights have been made in April 2019, May 2019 and February 2020 with an average GSD of 2–3 cm. The image processing has been carried out using some field surveyed GNSS ground control points and the RTK positioning of the UAV with errors lower than 0.03 m and 0.04 m in XY and Z, respectively. Then DSMs and orthophotographs were obtained with a resolution of 0.10 m and 0.05 m, respectively, and DSM of differences (DoDs) were calculated, with an uncertainty of about ±0.15 m. Finally, the DoDs were analysed in the GIS, in order to calculate the height differences and volumes between the three flights. The analysis has showed the areas affected by the gully erosion processes that correspond mainly to ground descents due to significant channel erosion and mass movements at the steep sidewalls. Considering the balance between depletion and deposition processes, the average height differences is about −0.03 m and the volume is about −42 m3, that is the depletion predominates. The main changes have been detected in the second period (May 2019–February 2020), while in the first one (April 2019–May 2019) they are practically insignificant and limited to small areas.

Low Power FPGA Implementation of Multi-View Video Coding with Hybrid Compression and Decompression Algorithm

The video is one of the most useful and most appealing medium to represent some information. More usage of digital multi-media via communications media, wireless communications, intranet, internet and cellular mobile leads to the uncontrollable growth of data in media. The video compression technique is used in this research work to improve the processing speed of the entire system. In this work, Low Cost - Multi Video Coding - Hybrid Compression and Decompression (LC-MVC-HCD) method is used to reduce computation complexity. The combinational of Discrete Wavelet Transform (DWT) and Discrete Cosine Transform (DCT) algorithms are denoted as hybrid algorithm. Based on this hybrid algorithm, the compression process is performing which improves the video coding efficiency of MVC. The LC-MVC-HCD methodwas implemented in the Matlab, Xilinx and Cadence tool. In Application Specific Integrated Circuit (ASIC) implementation, the area, power, and delay minimized by using the cadence encounter tool with 180nm and 45nm technology. In Field Programmable Gate Array (FPGA) implementation, the number of Lookup Tables (LUTs), slice, and flip-flop are minimized based on two different kinds of Virtex devices such as Virtex -6 and Virtex-7. In Matlab, Peak Signal to Noise Ratio (PSNR), computational time and bit error rate were analyzed for the LC-MVC-HCD method. The experimental outcome showed that the proposed methodology has improved performance ASIC and FPGA up to 2-3% compared to existing methods like Direct mode decision MVC and LC-MVC-DWT.

Interaction with a Problem Solving Multi Video Lecture: Observing Students from Distance and Traditional Learning Courses

The recording of lectures has become common as a way to produce video-based instructional material. Even though the material is often produced using more than one video source - the instructor and the slide, for instance - the result is usually a single video stream.
 We built a system prototype that allows the recording of several video streams associated with a lecture, including the instructor, projected slides, and information presented by the instructor via a computer (software or other videos, for instance). The several video streams, orchestrated using contextual and control information, are used to produce an interactive multi video object.
 The interactive nature of our novel multi video object offers students several alternatives for watching the lecture. When the multi video is used by students of traditional and distance learning courses, is opportune to investigate if there are differences in how students watch and interact with the multi video.
 We captured a problem solving lecture in the theme of Database Design our system. The resulting interactive multivideo object was offered to two groups of students as extra learning material, in preparation for exams. One of the groups attended a traditional, classroom-based course, and the other group attended a distance learning course. In this paper we first give a brief overview of our system, and then we present observations of how both groups of students interacted with the multi video multimedia learning object. We could observe, for instance, that students from the traditional course used the alternative views allowed by multi video more than students from the distance learning course, while students from the distance learning course spent more time watching and interacted more with the interactive multi video.

Standarisasi Observer OSCE dengan Rubrik dan Multivideo

Background: One of the factors influencing the validity and reliability of the assessment is the standardization of the observers in assessing students’ performance. A recent study by Setiawan (2011) found that there is differences in the standard of assessment used by general practitioners and specialized doctors in assessing students in OSCE.7 These differences are considered to be harmful for the students, therefore needs to be improved. Several training methods are developed to overcome the problem. This study aims to assess whether rubric and multi video can be used as a means of standardization of OSCE observers.Method: This was an experimental action research. The instruments used in this study were checklist, rubric, and video recording of students doing OSCE (n=5), which further be called multi-video. The subjects of the study were the OSCE observers in station Integrated Patient Management (IPM) who were divided into control and treatment group. The subjects assessed students’ performance from the multi-video in two data collection sessions. In the first session, both control and treatment group used checklist for assessing the multi-video. Furthermore in the second session, the control group did as the first data collection session, while the treatment group used checklist and rubric for assessing the multivideo. The result of which compared and tested using independent sample t-test.Results: As many as 33 observers, which consists of 23 general practitioners (GP) and 10 specialized doctors (SP), participated in the first data collection session. In the second data collection session, 28 observers consist of 20 GPs and 8 SPs participated. The result of the first data collection session, which used only checklist as an instrument, showed a significant difference in the standard of assessment used by the GPS and SPs (p<0.05), whereas the second data collection session, which used rubric as an additional instrument for the treatment group, showed no significant difference between GPs and SPs in the standard of assessment (p>0.05).Conclusion: Rubrics and multi video can be used as a means of standardization of OSCE observer in assessing students’ performance.

Intraguild predation by aphidophagous predators on parasitised aphids: the use of multiple video cameras

AbstractA video technique that allows simultaneous behavioural observations of several experimental replicates under field and laboratory conditions is described. The technique was used to analyse predation risk of parasitised aphids in a sugar beet field. The images of 16 black and white video cameras were recorded by a video multiplexer in combination with a time‐lapse video recorder. Each camera was weather protected and equipped with a single infrared diode to allow observations during night times. Single leaves carrying aphid mummies only or mummies and unparasitised aphids were monitored. All colonies were exposed to predation and parasitation by the community of natural enemies in the field. Colonies with mummies and unparasitised aphids were visited significantly more often by predators than those without additional aphids. Predators also stayed significantly longer in patches with unparasitised aphids. Although an equal proportion of aphid mummies were destroyed in both treatments, the video analysis showed differences in predator species spectrum between treatments. In patches with aphids, coccinellid and hemipteran predators preyed on mummies, while in patches with only mummies, chrysopids accounted for most of the damage. The decrease in parasitoid survival could be attributed to the increasing number of predator visits in aphid patches and to a lesser extent to the decreasing number of unparasitised aphids (alternative prey). Parasitoid survival in colonies without alternative prey was correlated with the number of predator visits and the time predators spent on a leaf.Continuous video observations gave additional behavioural information for the interpretation of field data. Other prospective research fields for the use of the multi video camera technique are outlined and general advantages and disadvantages are discussed.