{ "culture": "en-US", "name": "", "guid": "", "catalogPath": "", "snippet": "Creation of a feature data class with a table schema that has useful attributes to meet the needs of the users. This feature class will; allow agencies to see zoning areas and classifications for parcel buildings, create useful data for use in investigations, as well as knowing what buildings may be at risk during environmental disasters.", "description": "

Initial Data Capture: <\/SPAN><\/P>

Building were originally digitized using ESRI construction tools such as rectangle and polygon. Textron Feature Analyst was then used to digitize buildings using a semi-automated polygon capture tool as well as a fully automated supervised learning method. The method that proved to be most effective was the semi-automated polygon capture tool as the fully automated process produced polygons that required extensive cleanup. This tool increased the speed and accuracy of digitizing by 40%.<\/SPAN><\/P>

Purpose of Data Created: <\/SPAN><\/P>

To supplement our GIS viewers with a searchable feature class of structures within Ventura County that can aid in analysis for multiple agencies and the public at large.<\/SPAN><\/P>

Types of Data Used: <\/SPAN><\/P>

Aerial Imagery (Pictometry 2015, 9inch ortho/oblique, Pictometry 2018, 6inch ortho/oblique) Simi Valley Lidar Data (Q2 Harris Corp Lidar) <\/SPAN><\/P>

Coverage of Data:<\/SPAN><\/P>

Buildings have been collected from the aerial imageries extent. The 2015 imagery coverage the south county from the north in Ojai to the south in thousand oaks, to the east in Simi Valley, and to the West in the county line with Santa Barbara. Lockwood Valley was also captured in the 2015 imagery. To collect buildings for the wilderness areas we needed to use the imagery from 2007 when we last flew aerial imagery for the entire county. 2018 Imagery was used to capture buildings that were built after 2015.<\/SPAN><\/P>

Schema: <\/SPAN><\/P>

  • Fields: APN, Image Date, Image Source, Building Type, Building Description, Address, City, Zip, Data Source, Parcel Data (Year Built, Basement yes/no, Number of Floors) Zoning Data (Main Building, Out Building, Garage), First Floor Elevation, Rough Building Height, X/Y Coordinates, Dimensions. <\/SPAN><\/SPAN><\/P><\/LI><\/UL>

    Confidence Levels/Methods:<\/SPAN><\/P>

    • Address data: <\/SPAN><\/SPAN>90% <\/SPAN><\/SPAN>All Buildings should have an address if they appear to be a building that would normally need an address (Main Residence). To create an address, we do a spatial join on the parcels from the centroid of a building polygon and extract the address data and APN. To collect the missing addresses, we can do a spatial join between the master address and the parcels and then the parcels back to the building polygons. Using a summarize to the APN field we will be able to identify the parcels that have multiple buildings and delete the address information for the buildings that are not a main residence.<\/SPAN><\/SPAN><\/P><\/LI>

    • Building Type Data: <\/SPAN><\/SPAN>99% <\/SPAN><\/SPAN>All buildings should have a building type according to the site use category code provided from the parcel table information. To further classify multiple buildings on parcels in residential areas, the shape area field was used to identify building polygons greater than 600 square feet as an occupied residence and all other buildings less than that size as outbuildings. All parcels, inparticular parcels with multiple buildings, are subject to classification error. Further defining could be possible with extensive quality control <\/SPAN><\/P><\/LI>

    • APN Data: <\/SPAN><\/SPAN>98% <\/SPAN><\/SPAN>All buildings have received APN data from their associated parcel after a spatial join was performed. Building overlapping parcel lines had their centroid derived which allowed for an accurate spatial join.<\/SPAN><\/SPAN><\/P><\/LI><\/UL>

      Troubleshooting Required: <\/SPAN><\/P>

      Buildings would sometimes overlap parcel lines making spatial joining inaccurate. To fix this you create a point from the centroid of the building polygon, join the parcel information to the point, then join the point with the parcel information back to the building polygon.<\/SPAN><\/P>

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