Ross, but does your customer as I understand need "just" data/graphs/stats about people flow/presence? If so, maybe you could give the "appearance" of integration in the VMS if this version of Lenel they have had, for example, the availability of an interface with an internal browser, where to "embed" a web-based dashboard collecting the data from some video-analytics-based modules, eventually running edge into Axis cameras.
In general, at today VMS and Business Intelligence are often still looking like separate worlds, with separate goals.. VMS is often still more focused on security market "just" receiving and managing alerts from analytics or whatever else connected, but not continuous data like for example the counting, nor specific interfaces for specific functions showing graphs/stats/.. On the other side, the business intelligence products are focused on marketing/retail market, with products based on strong databases, with service providers making wonderful reports/graphs/stats/.. but definitely not connected to other security issues.. And in general, to complicate further things, mainly in big organizations, the security managers and the marketing managers are 2 completely different departments, often even "not talking" to eachothers (maybe in US they do, but you can imagine in Italy....;))....).
Yet, the same camera counting people by day, by night it could detect intruders for example.. Or people flow counting for marketing stats may also be used to estimate if an area is overcrowded and it may definitely be applied also to generate an alert for security purpouses as well.. Someone is starting to provide this (Milestone, Aimetis, ..), and imho I think it's logical we are going towards there time by time. I think it's going to be soon the same convergence path that we are seeing in these years about Security <-> IP/Informatics markets: we are going to see more and more solutions of VMS for managing both security and business intelligence issues.. Even if, as Marc correctly wrote, it's technically different to build and above all to manage a database for some hundreds of alerts per day or for some millions of records of counting per day..
But, coming back strictly to your problem (sorry for the digression.....;)..), as written before Axis has many partners providing people counting functions and eventually collecting and showing reports/graphs/stats by web-based applications, that you could then try to "embed" into Lenel interface, if a browser is available. This, if we must keep up these constrains: I mean, Axis cameras + people counting technologies + Lenel VMS appearing as single integrated solution.
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