Joshua B. Logan
Amy E. East
Andrew C. Ritchie
20200527
Orthomosaic imagery for Whiskeytown Lake and surrounding area, 2019-06-03
GeoTIFF
data release
DOI:10.5066/P9HEDYNT
Pacific Coastal and Marine Science Center, Santa Cruz, California
U.S. Geological Survey
https://doi.org/10.5066/P9HEDYNT
https://www.sciencebase.gov/catalog/item/5e696548e4b01d50925e7200
Joshua B. Logan
Peter Dartnell
Amy E. East
Andrew C. Ritchie
2020
Bathymetry, topography and orthomosaic imagery for Whiskeytown Lake, northern California
data release
DOI:10.5066/P9HEDYNT
Pacific Coastal and Marine Science Center, Santa Cruz, CA
U.S. Geological Survey
https://doi.org/10.5066/P9HEDYNT
https://www.sciencebase.gov/catalog/item/5dfbba2fe4b0b5e61c073327
This portion of the data release presents an RGB orthomosaic image of Whiskeytown Lake and the surrounding area derived from Structure from Motion (SfM) processing of aerial imagery acquired on 2019-06-03. The orthomosaic is available in a high-resolution 6-centimeter (cm) version, as well as a medium-resolution 25 cm version. The high-resolution version is divided into two tiles (east and west) to reduce file download sizes. All imagery is provided in a three-band cloud-optimized GeoTIFF format, with 8-bit unsigned integer values compressed using high-quality JPEG compression. The raw imagery used to create the orthomosaic was acquired from a manned aircraft on 2019-06-03. The acquisition flight was conducted by The 111th Group Aerial Photography, using a Nikon D850 camera. The acquisition covered two areas-of-interest (AOI) at different scales. The AOI for this dataset (referred to as AOI-A) covered the area immediately surrounding Whiskeytown Lake, which is the same area imaged in the 2018-12-02 acquisition (also available as a part of this data release). The imagery was acquired from an approximate altitude of 610 meters (2,000 feet) above ground level, to produce a nominal ground-sample distance (pixel size) of 5 centimeters (2 inches). An onboard dual-frequency GPS receiver was used to record the precise time and position of each image. Coordinates for ground control points consisting of photo-identifiable objects were measured independently using survey-grade post-processed kinematic (PPK) GPS.
This RGB orthomosaic image was created to help evaluate the post-fire conditions on the exposed margins of Whiskeytown Lake as well as the exposed, unvegetated portions of the surrounding watersheds. It is intended for use by scientists, managers, and the general public. The orthomosaic can be used with geographic information systems (GIS) software for research purposes.
Additional information about the field activities from which these data were derived is available online at:
http://cmgds.marine.usgs.gov/fan_info.php?fan=2018-686-FA
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Data used in creating this data product were collected under the Department of the Interior, National Park Service Scientific Research and Collecting Permit WHIS-2018-SCI-0023 and WHIS-2019-SCI-0011.
20190603
20190603
ground condition at time data were collected
None planned
-122.633557
-122.515043
40.663021
40.588788
USGS Metadata Identifier
USGS:5e7d44c1e4b01d5092751e1f
ISO 19115 Topic Category
elevation
Data Categories for Marine Planning
Bathymetry and Elevation
USGS Thesaurus
topography
topographic maps
remote sensing
geomorphology
aerial photography
image mosaics
fires
Marine Realms Information Bank (MRIB) keywords
photography
remote sensing
fragile ecosystems
None
U.S. Geological Survey
USGS
Coastal and Marine Hazards and Resources Program
CMHRP
Pacific Coastal and Marine Science Center
PCMSC
reservoir
wildfires
Carr fire
Geographic Names Information System (GNIS)
State of California
Whiskeytown-Shasta-Trinity National Recreation Area
Whiskeytown Lake
None
USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. This information is not intended for navigation purposes.
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060
831-427-4747
pcmsc_data@usgs.gov
https://www.sciencebase.gov/catalog/file/get/5e7d44c1e4b01d5092751e1f?name=Whiskeytown_2019-06-03_orthomosaic_browse.png
RGB orthomosaic image from 2019-06-03.
PNG
Data collection was funded by the U.S. Geological Survey. Data acquisition was conducted by The 111th Group Aerial Photography. Data processing was done by the U.S. Geological Survey.
Microsoft Windows 10, Agisoft PhotoScan version 1.4.4 through Agisoft Metashape 1.5.3, QGIS 3.04 through 3.12, and GDAL 3.0.4 through 3.1.0.
No formal attribute accuracy tests were conducted.
No formal logical accuracy tests were conducted.
Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details.
Horizontal positional accuracy was evaluated by comparing the positions of 17 independent photo-identifiable ground control check points measured with survey-grade post-processed kinematic (PPK) GPS with their estimated positions derived from the structure from motion (SfM) processing workflow. The root-mean-square error (RMSE) of the residual values of the measured positions versus the SfM-estimated positions was 0.165 meters. It should be noted that this estimate is for unvegetated, bare ground areas only. Additional sources of error such as noise or blurriness within the source imagery, poor terrain reconstruction in areas of uniform color and texture such as roads and parking lots, poor terrain reconstruction on small islands surrounded by water, and vegetation artifacts may cause additional errors in portions of the orthomosaic which are likely outside the stated uncertainty bounds.
Vertical positional accuracy was not evaluated for this data product.
Aerial imagery was collected by the 111th Group, Inc. on 2019-06-03 using a Nikon D-850 mounted in a nadir orientation. For this dataset, the images were acquired between 22:09 and 23:34 Universal Coordinated Time (UTC) (15:09 to 16:34 Pacific Daylight Time (PDT)). The imagery was acquired from an approximate altitude of 610 meters (2,000 feet) above ground level, to produce a nominal ground sample distance (pixel size) of 5 centimeters (2 inches). A total of 1,881 images were acquired in the survey area, with an approximate 70 percent along-line image overlap (forelap) and 50 percent side-to-side overlap (sidelap). An onboard dual-frequency GPS receiver was used to record the precise shutter time and approximate position of each image.
20190603
Patrick Belanger
The 111th Group Inc
mailing and physical
13025 Murphy Ave. Suite 100
San Martin
CA
95046
408-683-9111
pat@the111th.com
Ground control was established after the image acquisition by measuring the positions of approximately 43 photo-identifiable marks or objects using survey-grade post-processed-kinematic (PPK) GPS equipment. All measurements were referenced to a static base station operating on a temporary benchmark within the survey area. The position of the base station was established using the National Geodetic Survey Online Positioning User Service (OPUS).
20190516
Joshua Logan
U.S. Geological Survey, Pacific Coastal and Marine Science Center
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060
831-460-7519
jlogan@usgs.gov
Structure from Motion (SfM) processing techniques were used to create the Digital Surface Model and Orthomosaic in the Agisoft Photoscan/Metashape software package using the following work flow:
1. Imagery was geotagged using a combination of post-processed-kinematic (PPK)GPS positions and DGPS positions from the onboard single-frequency GPS unit.
2. Initial image alignment was performed with the following parameters - Accuracy: 'High'; Pair selection: 'reference', 'generic'; Key point limit: 0 (unlimited); Tie point limit: 0 (unlimited).
3. Optimization and lens calibration parameters f, cx, cy, k1, k2, k3, p1, and p2 were included.
4. Ground control points (GCPs) previously measured with PPK GPS were manually identified and placed in the imagery.
5. Sparse point cloud error reduction was performed using an iterative gradual selection and camera optimization process with the following parameters: Reconstruction Uncertainty: 10; Projection Accuracy: 3; Reconstruction Error: 0.3.
6. A dense point cloud was created using the 'high' accuracy setting, with 'aggressive' depth filtering.
7. Ground and low-noise points were identified using the 'Classify Ground Points' tool with the following parameters: Max. Angle: 15 degrees; Max. Distance: 0.5 meters; Cell Size: 5 meters. Due to the prevalence of vegetation and tree cover in most areas, it is not expected that this step removed all of the vegetation points. The dense point cloud was exported to LAZ format.
8. An initial Digital Surface Model (DSM) with a native resolution of 0.116 meters per pixel was created using the ground classified points from the dense point cloud. An exterior boundary was digitized and used as a clipping mask to exclude obvious edge artifacts and large areas of interpolation. The DSM was exported to a GeoTIFF format with a 0.250-meter pixel resolution.
9. An RGB orthomosaic with a native resolution of 0.058 meters per pixel was created using the DSM as the orthorectification surface. The orthomosaic was exported to a GeoTIFF format at two resolutions: 0.060-meter pixels, and 0.250-meter pixels.
10. The RGB orthomosaic was converted to a cloud optimized GeoTIFF format for compatibility with cloud storage services using the GDAL software package. The orthomosaic was scaled to byte values and compressed using JPEG compression, with a quality of 90. The higher-resolution orthomosaic was divided into an east and west tile to reduce the file size, while the lower-resolution version was kept as one file.
2019
Joshua Logan
U.S. Geological Survey, Pacific Coastal and Marine Science Center
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060
831-460-7519
jlogan@usgs.gov
Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed.
20201019
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Raster
Pixel
32768
39936
Universal Transverse Mercator
10
0.9996
-123.00000
0.00000
500000.0
0.00
coordinate pair
0.250
0.250
Meters
North American Datum of 1983, 2011 realization (NAD83(2011)).
GRS 1980
6378137.00
298.257222101
GeoTIFF
GeoTIFF containing RGB color bands.
Producer defined
Band_1
Red band
Producer defined
0
255
Band_2
Green band
Producer defined
0
255
Band_3
Blue band
Producer defined
0
255
U.S. Geological Survey - ScienceBase
mailing and physical
Denver Federal Center, Building 810, Mail Stop 302
Denver
CO
80225
1-888-275-8747
sciencebase@usgs.gov
The RGB orthomosaic images are available as Cloud Optimized GeoTIFF files in two resolutions. High-resolution 6 cm (Whiskeytown_2019-06-03_orthomosaic_6cm_east.tif and Whiskeytown_2019-06-03_orthomosaic_6cm_west.tif), and medium-resolution 25 cm (Whiskeytown_2019-06-03_orthomosaic_25cm.tif).
Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
GeoTIFF
GDAL 3.1.0dev
Cloud Optimized GeoTIFF contains a medium-resolution (25 cm) three-band RGB orthomosaic with 8-bit unsigned integer values stored with high quality JPEG compression (Whiskeytown_2019-06-03_orthomosaic_25cm.tif).
none
167
https://www.sciencebase.gov/catalog/file/get/5e7d44c1e4b01d5092751e1f?name=Whiskeytown_2019-06-03_orthomosaic_25cm.tif
https://www.sciencebase.gov/catalog/item/5e7d44c1e4b01d5092751e1f
https://doi.org/10.5066/P9HEDYNT
Data can be downloaded using the Network_Resource_Name links. The first link is a direct link to download the 25 cm orthomosaic. The second link points to a landing page with the all orthomosaics, metadata, and browse image. The third link points to the landing page for the entire data release, including links to pages of the various data files.
GeoTIFF
GDAL 3.1.0dev
Cloud Optimized GeoTIFF contains a high-resolution (6 cm) three-band RGB orthomosaic with 8-bit unsigned integer values stored with high quality JPEG compression, (east tile: Whiskeytown_2019-06-03_orthomosaic_6cm_east.tif).
none
1000
https://www.sciencebase.gov/catalog/file/get/5e7d44c1e4b01d5092751e1f?Whiskeytown_2019-06-03_orthomosaic_6cm_east.tif
https://www.sciencebase.gov/catalog/item/5e7d44c1e4b01d5092751e1f
https://doi.org/10.5066/P9HEDYNT
Data can be downloaded using the Network_Resource_Name links. The first link is a direct link to download the eastern portion of the 6 cm orthomosaic. The second link points to a landing page with the all orthomosaics, metadata, and browse image. The third link points to the landing page for the entire data release, including links to pages of the various data files.
GeoTIFF
GDAL 3.1.0dev
Cloud Optimized GeoTIFF contains a high-resolution (6 cm) three-band RGB orthomosaic with 8-bit unsigned integer values stored with high quality JPEG compression, (west tile: Whiskeytown_2019-06-03_orthomosaic_6cm_west.tif).
none
1210
https://www.sciencebase.gov/catalog/file/get/5e7d44c1e4b01d5092751e1f?Whiskeytown_2019-06-03_orthomosaic_6cm_west.tif
https://www.sciencebase.gov/catalog/item/5e7d44c1e4b01d5092751e1f
https://doi.org/10.5066/P9HEDYNT
Data can be downloaded using the Network_Resource_Name links. The first link is a direct link to download the western portion of the 6 cm orthomosaic. The second link points to a landing page with the all orthomosaics, metadata, and browse image. The third link points to the landing page for the entire data release, including links to pages of the various data files.
None.
These data can be viewed with GIS software or other software capable of displaying geospatial raster data.
20201019
U.S. Geological Survey, Pacific Coastal and Marine Science Center
PCMSC Science Data Coordinator
mailing and physical
2885 Mission Street
Santa Cruz
CA
95060
831-427-4747
pcmsc_data@usgs.gov
Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998