This data set is a statewide raster mosaic of 2010, 4 band natural color and color infrared, 1 meter ground sample distance imagery for Connecticut from the National Agriculture Imagery Program (NAIP). NAIP acquires digital ortho imagery during the agricultural growing seasons in the continental U.S.. A primary goal of the NAIP program is to enable availability of ortho imagery within one year of acquisition. NAIP provides four main products: 1 meter ground sample distance (GSD) ortho imagery rectified to a horizontal accuracy of within +/- 5 meters of reference digital ortho quarter quads (DOQQ's) from the National Digital Ortho Program (NDOP); 2 meter GSD ortho imagery rectified to within +/- 10 meters of reference DOQQs; 1 meter GSD ortho imagery rectified to within +/- 6 meters to true ground; and, 2 meter GSD ortho imagery rectified to within +/- 10 meters to true ground. The tiling format of NAIP imagery is based on a 3.75' x 3.75' quarter quadrangle with a 300 meter buffer on all four sides. NAIP quarter quads are formatted to the UTM coordinate system using NAD83. NAIP imagery may contain as much as 10% cloud cover per tile.
NAIP imagery is available for distribution within 60 days of the end of a flying season and is intended to provide current information of agricultural conditions in support of USDA farm programs. For USDA Farm Service Agency, the 1 meter GSD product provides an ortho image base for Common Land Unit boundaries and other data sets. The 1 meter NAIP imagery is generally acquired in projects covering full states in cooperation with state government and other federal agencies who use the imagery for a variety of purposes including land use planning and natural resource assessment. With an annual cycle, NAIP is also used for disaster response often providing the most current pre-event imagery. While suitable for a variety of uses the 2 meter GSD NAIP imagery is primarily intended to assess crop condition and compliance to USDA farm program conditions. The 2 meter imagery is generally acquired only for agricultural areas within state projects.
This statewide raster mosaic was prepared by the State of Connecticut, Department of Environmental Protection (CT DEP) using 2010, 4 color band, 1 meter ground sample distance imagery (input rasters) from the USDA-FSA-APFO Aerial Photography Field Office. These original input rasters are in GeoTIFF format and because there are two UTM Zones in Connecticut, the input rasters are in either the NAD 1983 UTM Zone 18N Meters or NAD 1983 UTM Zone 19N Meters. The individual rasters were projected to NAD 1983 StatePlane Connecticut FIPS 0600 Feet and merged together in the resulting statewide mosaic. Using ESRI ArcGIS 9.2 software, statistics for the pixel color values in the image have been calculated and stored with the imagery data. This has been done to improve drawing performance and to easily manage how color bands are displayed. Depending on the GIS software used to view the image, the creation of these statistics may result in a default display of the raster mosaic in extreme colors values rather than in a natural color scheme. However, this can be changed with most software. For example, when viewing the imagery with ESRI ArcMap software, change the Symbology Stretch setting from a value of Standard Deviation to None to achieve a more natural range of colors for both color and color infrared displays. Apply these band settings to obtain full color imagery. Red = Band 1 Green = Band 2 Blue = Band 3 Apply these band settings to obtain color infrared imagery. Red = Band 4 Green = Band 1 Blue = Band 2
Imagery may be replaced to address defects found in a small number of products through quality assurance processes. Imagery containing defects that require the acquisition of new imagery, such as excessive cloud cover, specular reflectance, etc., will not be replaced within a NAIP project year.
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NAIP 3.75 minute tile file names are based on the USGS quadrangle naming convention.
FSA Digital Orthophoto Specs.
Digital Georectifed Image (2010 NAIP 1 meter DOQQ). Each image is in GeoTIFF format. Depending in the location, NAIP quarter quads are either in NAD 1983 UTM Zone 18N or NAD 1983 UTM Zone 19N coordinate system. UTM Zones 18N and 19N encompass portions of Connecticut. NAIP DOQQ (3.75 minute tile) file names are based on the USGS quadrangle naming convention.
Statewide raster mosaic of all NAIP DOQQ input rasters. The raster mosaic is in the Connecticut State Plane Coordinate System, North American Datum of 1983 (NAD83).
The imagery was collected using ADS40-SH51 and ADS40-SH52 digital sensors. Collection was performed using a combination of twin-engine aircraft flying at an average flying height of 17,500 above mean terrain with 23% sidelap, giving the collected data nominal ground sampling distance of 0.55 meters. Based-upon the CCD Array configuration present in the ADS40 digital sensor, imagery for each flight line is 12,000-pixels in width. Red, Green, Blue, Near-Infrared and Panchromatic image bands were collected. Collected data was downloaded to portable hard drives and shipped to the processing facility daily. Raw flight data was extracted from external data drives using GPro software. Airborne GPS / IMU data was post-processed using IPAS, PosPac and/or TerraPos software and reviewed to ensure sufficient accuracy for project requirements. Using GPro and Pictovera software, planar rectified images were generated from the collected data for use in image quality review. The planar rectified images were generated at five meter resolution using a two standard deviation histogram stretch. Factors considered during this review included but were not limited to the presence of smoke and/or cloud cover, contrails, light conditions, sun glint and any sensor or hardware-related issues that potentially could result in faulty data. When necessary, image strips identified as not meeting image quality specifications were re-flown to obtain suitable imagery. Aerotriangulation blocks were defined primarily by order of acquisition and consisted of four to seventeen strips. Image tie points providing the observations for the least squares bundle adjustment were selected from the images using an autocorrelation algorithm. Photogrammetric control points consisted of photo identifiable control points, collected using GPS field survey techniques. The control points were loaded in to a softcopy workstation and measured in the acquired image strips. A least squares bundle adjustment of image pass points, control points and the ABGPS was performed to develop an aerotriangulation solution for each block using Pictovera software. Upon final bundle adjustment, the triangulated strips were ortho-rectified to the USGS NED DEM for the project area. The images were re-sampled from the raw resolution of 0.55 meters to the required resolution of 1.0 meters. Positional accuracy was reviewed in the rectified imagery by visually verifying the horizontal positioning of the known photo-identifiable survey locations using ArcGIS software. The red, green, blue, and NIR bands were combined to generate a final ortho-rectified image strip. The ADS40 sensor collects twelve bit image data which requires radiometric adjustment for output in standard eight bit image channels. The ortho-rectified image strips were produced with the full 12 bit data range, allowing radiometric adjustment to 8 bit range to be performed on a strip by strip basis during the final mosaicking steps. The imagery was mosaicked using manual seamline generation in Orthovista Seam Editor (OVSE). The 12 bit data range was adjusted for display in standard eight bit image channels by defining a piecewise histogram stretch using OrthoVista software. A constant stretch was defined for each image collection period, and then strip by strip adjustments were made as needed to account for changes in sun angle and azimuth during the collection period. Strip adjustments were also made to match the strips histograms as closely as possible to APFO specified histogram metrics and color balance requirements. Automated balancing algorithms were applied to account for bi-directional reflectance as a final step before the conversion to 8 bit data range. APFO specified DOQQs were extracted from the final mosaic in GeoTIFF format. 4-Band DOQQs were produced and 3-Band RGB CCMs were created. DOQQs corresponding to an individual CCM were reviewed for overall color balance within the CCM. Local corrections were made where necessary to ensure uniformity within the CCM. In the case of DOQQs occurring in more than one CCM, a separate version of the image was generated and balanced for each CCM it occurred in.
Using ESRI ArcGIS 9.2 software, an empty raster dataset was created and subequently populated with input rasters to create a statewide raster mosaic. The State of Connecticut, Department of Environmental Protection obtained these input rasters from the USDA-FSA-APFO Aerial Photography Field Office, 2222 West 2300 South, Salt Lake City, 84119-2020. STEP 1 - Create Raster Dataset - The Coordinate System for the raster dataset is NAD_1983_StatePlane_Connecticut_FIPS_0600_Feet. The image compression type is JPEG with a compression quality of 90. The Pyramid Reference Point X and Y coordinate are 687800 and 1015180, respectively. Bands: 4. Pyramids: 12 Bilinear. The Pixel Type is 8_BIT_UNSIGNED, which supports index values from 0 to 255. Raster statistics were built for all 4 bands. Below is a record of the ESRI Geoprocessing CreateRasterDataset command and arguments that created the empty raster dataset. CreateRasterDataset "Database Connections\10.18.8.60.depgis@dep_92dc.sde" ORTHO_2010_4BAND_NAIP # 8_BIT_UNSIGNED PROJCS['NAD_1983_StatePlane_Connecticut_FIPS_0600_Feet', GEOGCS['GCS_North_American_1983', DATUM['D_North_American_1983', SPHEROID['GRS_1980',6378137.0,298.257222101]], PRIMEM['Greenwich',0.0], UNIT['Degree',0.0174532925199433]], PROJECTION['Lambert_Conformal_Conic'], PARAMETER['False_Easting',999999.999996], PARAMETER['False_Northing',499999.999998], PARAMETER['Central_Meridian',-72.75], PARAMETER['Standard_Parallel_1',41.2], PARAMETER['Standard_Parallel_2',41.86666666666667], PARAMETER['Latitude_Of_Origin',40.83333333333334], UNIT['Foot_US',0.3048006096012192]] 4 DEPRASTER "PYRAMIDS 12 BILINEAR" "128 128" "JPEG 90" "687800 1015180" "Database Connections\10.18.8.60.depgis@dep_92dc.sde\depgis.DEP.ORTHO_2010_4BAND_NAIP" STEP 2 - Mosaic 412 quarter quadrangle input rasters that cover Connecticut. The Ignore Background Value was set to one (1). The NoData value was left blank. The Mosaicking Tolerance value was set to zero (0). Consequently, pixel values in the raster mosaic resulted from a resampling of pixels values from individual input rasters due to the difference in alignment of input and mosaic (target) pixels. Note, in the resulting mosaic, the input rasters in NAD 1983 UTM Zone 18N Meters and NAD 1983 UTM Zone 19N Meters were projected to NAD 1983 StatePlane Connecticut FIPS 0600 Feet. Below is an example usage of the ESRI Geoprocessing Mosaic command and arguments used to mosaic 4 (quarter quadrangle) input rasters in TIFF format. Mosaic X:\Base_Map_Imagery\Ortho_2010_Color_NAIP_1m\tiff_format_utm19\42071\m_4207157_se_19_1_20100814.tif; X:\Base_Map_Imagery\Ortho_2010_Color_NAIP_1m\tiff_format_utm19\42071\m_4207157_sw_19_1_20100814.tif; X:\Base_Map_Imagery\Ortho_2010_Color_NAIP_1m\tiff_format_utm19\42071\m_4207158_se_19_1_20100814.tif; X:\Base_Map_Imagery\Ortho_2010_Color_NAIP_1m\tiff_format_utm19\42071\m_4207158_sw_19_1_20100814.tif "Database Connections\10.18.8.60.depgis@dep_92dc.sde\DEPGIS.DEP.ORTHO_2010_4BAND_NAIP" LAST FIRST 1 # NONE 0 "Database Connections\10.18.8.60.depgis@dep_92dc.sde\DEPGIS.DEP.ORTHO_2010_4BAND_NAIP" STEP 3 - Calculate Statistics. Using ESRI ArcGIS 9.2 software, statistics for the pixel color values in the image have been calculated and stored with the imagery data. This has been done to improve drawing performance and to easily manage how color bands are displayed. Depending on the GIS software used to view the image, the creation of these statistics may result in a default display of the raster mosaic in extreme colors values rather than in a natural color scheme, for example. However, this can be changed with most software. For example, when viewing the imagery with ESRI ArcMap software, change the Symbology Stretch setting from a value of Standard Deviation to None to achieve a more natural range of colors for both color and color infrared displays.
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Copied data from ArcSDE 9.2 raster dataset to FileGeodatabase 9.3 raster dataset format for data distribution purposes. The image properties for the FileGeodatabase 9.3 raster dataset are the same as those for the version in ArcSDE. The image compression type is JPEG with a compression quality of 90. Pyramids: 12 Bilinear. The Pixel Type is 8_BIT_UNSIGNED, which supports index values from 0 to 255. Bands: 4. Raster statistics were built for all 4 bands. Below is a record of the ESRI Geoprocessing CopyRaster command and arguments used in copying the data. CopyRaster "Database Connections\10.18.8.60.depgis@depview_92dc.sde\DEPGIS.DEP.ORTHO_2010_4BAND_NAIP" C:\Raster_format\Connecticut_Ortho_2008_NAIP.gdb\ORTHO_2010_4BAND_NAIP DEFAULTS # # NONE NONE 8_BIT_UNSIGNED
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32-bit pixels, 4 band color(RGBIR) values 0 - 255
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Although these data have been used by the State of Connecticut, no warranty, expressed or implied, is made by the State of Connecticut as to the accuracy of these data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata.
The data distributor does not provide custom GIS analysis or mapping services. Data is available in a standard format and may be converted to other formats, projections, coordinate systems, or selected for specific geographic regions by the party receiving the data.
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