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video anomaly detection matlab code
#1

Regular patterns
Many metrics follow some sort of regular patterns correlated to time. Websites commonly experience high activity during the day and low activity at night. This correlation with time make it easy to spot anomalies but when it doesn t it s a bit more difficult.
1. With time correlation
When the metric is correlated to time, the key point is to find it seasonality. When today s pattern is the same as yesterday, it seasonality is known as one day. It is common to find seasonality of one week because Saturday s patterns don t often follow Friday s patterns. Saturday s patterns often follow Saturday s patterns of the previous week. Because many metrics are correlated to human activity the seasonality is often weekly. But it could also be few second, hours, month or n-periods.
Simply by subtracting today patterns with it usual patterns (seasonality) create a new signal the difference metric . Due to randomness, the result signal should be pure noise with a mean of zero. Under such conditions, we can apply the normal distribution to detect anomalies. To put is simply, too high or too low in the values can be treated as anomalous.
substract seasonality
2.Without time correlation
The heartbeat signal have many recurring patterns. The heartbeat beat on average every 0.8s, but this is an average period not a fixed period of time. Moreover, the period and the value of the signal might change a lot due to physical activity, stress or any other psyche activity. So definitively, it isn t possible to take the patterns 0.8s ago to compare it with now s patterns.
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#2
In data mining, anomaly detection (also outlier detection) is the identification of items, events or observations which do not conform to an expected pattern or other items in a dataset. Typically the anomalous items will translate to some kind of problem such as bank fraud, a structural defect, medical problems or errors in a text. Anomalies are also referred to as outliers, novelties, noise, deviations and exceptions.
In particular in the context of abuse and network intrusion detection, the interesting objects are often not rare objects, but unexpected bursts in activity. This pattern does not adhere to the common statistical definition of an outlier as a rare object, and many outlier detection methods (in particular unsupervised methods) will fail on such data, unless it has been aggregated appropriately. Instead, a cluster analysis algorithm may be able to detect the micro clusters formed by these patterns.
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#3
Hi am Chandrashekar i would like to get details on video anomaly detection matlab code ..My friend said video crowd anomaly detection matlab code will be available here and i last studied in the college/school and now am doing project on crowd analysis i need your help on so please send matlab code to my mail [email protected]

Thank you
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#4
Hi am Ram i would like to get details on video anomaly detection matlab code ..My friend Justin said video anomaly detection matlab code will be available here and now i am living at .. and i last studied in the college/school .. and now am doing ..i need help on ..etc
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