Transcript Mapping the Path to Digital Camera Calibration

The Proposed USGS Plan
for
Digital Data Quality Assurance
Jon Christopherson
SAIC, Contractor to the USGS EROS
ASPRS Camera Calibration Session
March 9th, 2005
U.S. Department of the Interior
U.S. Geological Survey
National Center for EROS
Remote Sensing Technologies Group
1
Historical Role
USGS providing Camera Calibration service
since 1973
Not a “Certificate” or certification
Simply a report of camera characterization
Contained pass/fail criteria
Camera meets basic performance levels
Deliverable in those days was often just the film
Film required camera parameters to derive products
Barest minimum of product quality assurance!
And only if the product was film
U.S. Department of the Interior
U.S. Geological Survey
2
Changing Roles
Film is often not the delivered product today
Instead products derived from that film
Orthos, mosaics, GIS layers, etc.
USGS Camera Calibration Report still required
Necessary, but not sufficient to assure quality
Many more processes involved with producing
products today.
Can be multiple firms in the chain from photon to
final product
What has USGS Camera Cal report provided?
What more is needed?
U.S. Department of the Interior
U.S. Geological Survey
3
The USGS Proposed Plan
USGS proposed plan is:
Focused on Sensors
Focused on Processes
Focused on the End Products
End Goal is to Assure End Product Quality
U.S. Department of the Interior
U.S. Geological Survey
4
Focus on Sensors
Focus on Sensors - “Sensor Systems”
Without sensors there are no processes or products
Increasing capabilities and complexities will bring
challenges
The USGS is considering “Type Certification” of
digital systems
Certification would include not only sensors and
associated systems, but also the entire “chain”
USGS would like to work with manufacturers &
developers to certify product creation chain(s)
e.g. Leica ADS-40 with ADS40-specific calibration
technique(s), ADS40 processing software, etc.
U.S. Department of the Interior
U.S. Geological Survey
5
Sensors (cont.)
Type certification could include:
Understanding sensor/system designs
Operating parameters, limitations
Operating constraints – what is necessary to deliver
intended quality
Designers/Manufacturers know this best
USGS works with them to learn system capabilities
USGS to understand Mfr’s verification process
Observes/Participates in testing, validating
methods, verifying accuracy
U.S. Department of the Interior
U.S. Geological Survey
6
Sensors (cont.)
Goal is to understand:
The capabilities of system
The requirements for successful operation
Requirements for calibrations, methods, frequency,
etc.
What level of data quality can this system
reliably provide?
U.S. Department of the Interior
U.S. Geological Survey
7
Focus on Processes
Focus on Processes
All products are the result of processes
The quality of aerial mapping imagery is at least
as dependent on the processes as on sensors
Process control at least as important to
customers as sensors
Processes make/break the quality chain
U.S. Department of the Interior
U.S. Geological Survey
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Processes (cont.)
Processes include:
Flight planning, data collection & recording
Configuration maintenance of systems/software
Maintenance of sensor/systems
Calibration procedures, history
Data handling, particularly steps where data is processed
Processing software versions, etc.
Any other external inputs
All of this information must be documented
Much of this is ideally in the metadata associated
with the final product
U.S. Department of the Interior
U.S. Geological Survey
9
Processes (cont.)
Manufacturers are key to helping develop
standard processes
Flyers, industry, ASPRS/ISPRS are key also
Quality demands that processes are controlled
– and documented
Something like an ISO-9000 certification?
Or an ASPRS-certified Professional Practices?
U.S. Department of the Interior
U.S. Geological Survey
10
Focus on the End Products
The ultimate goal is to assure the quality of the
final product
Community has developed a reliance on USGS
Camera Calibration report
Implies that a good camera was used
More is needed
Community needs to know that good cameras,
systems and processes were used throughout!
U.S. Department of the Interior
U.S. Geological Survey
11
What This All Means
Hardware/Software Certification burden is transferred
from many individual flyers to (relatively) few
manufacturers
Allows more in-depth understanding of each system, working
directly with technologists
Helps keep burden of hardware/software performance on
those who developed it
Burden on flyers/producers now shifted to
processes
Insists that defined processes be carried out and
documented
Aids in troubleshooting, maintaining high standards
Flyers are/should be doing this anyway
U.S. Department of the Interior
U.S. Geological Survey
12
What This All Means (cont.)
USGS to work with ASPRS to promote education of new
standards for use by consumers
Many more factors affect data quality, data usefulness
Education required to best obtain & use new capabilities
Old “Camera Cal Report required ” boilerplate doesn’t cover it
all!
USGS Certification and documented processes
means more - a Greater Assurance of Data
Quality
We all benefit from that!
U.S. Department of the Interior
U.S. Geological Survey
13
We Are Not Alone
EuroSDR is exploring similar concepts and
processes for Europe
Professional organizations (ASPRS/ISPRS) are
in general agreement so far
Could it be possible to come up with universal
standards & practices?
U.S. Department of the Interior
U.S. Geological Survey
14
Work To Be Done:
USGS to continue building cooperation:
With Manufacturers
With partners (IADIWG, EuroSDR, ASPRS, ISPRS)
With Data Providers (flyers & processors)
With consumers/users
USGS to continue exploring/developing new
calibration & quality assurance tools & methods
Make tools available to public as appropriate
USGS to continue developing infrastructure
Continue assessing new systems, capabilities
USGS Needs Your Input and Ideas!
U.S. Department of the Interior
U.S. Geological Survey
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End
U.S. Department of the Interior
U.S. Geological Survey
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“Classes” of Digital Data
Industry needs “Classes” of Digital Products
Applies to those generating, processing, selling, buying
and working with these data
Can apply to aerial, satellite, even lead to standards for nonimaging products, e.g. LIDAR.
Will develop different quality “classes” of digital
mapping data
Based on resolution & accuracy
Initial Classes for geometric and spatial quality
Followed soon (?) by radiometric quality
USGS offers to lead standards development, with
ASPRS/ISPRS
U.S. Department of the Interior
U.S. Geological Survey
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Examples of Data Classes
The following are notional examples to illustrate what
data classes could be:
Class 0: No geometric/geodetic accuracy implied,
“Pretty pictures”
Class A: Ground Sample Distance (GSD) > 1.0 meter,
geometric accuracies <0.5pixel size
Class B: Ground Sample Distance (GSD) < 1.0 meter,
geometric accuracies <0.4m
Class C: GSD < 0.5m, geometric/geodetic <0.2m
Class D: GSD < than 0.15m, geometric/geodetic <0.1m
Class E: (Reserved for future capabilities)
U.S. Department of the Interior
U.S. Geological Survey
18
Work Needed to be Done
USGS to establish contacts points for manufacturers, begin
interaction
Funding – the longer we wait, the more it costs
USGS partially funded in FY05
Establish IADIWG funding mechanisms required for FY05
USGS and IADIWG need to define funding mechanisms for FY06
and FY07
Define infrastructure needed
In-situ ranges
Hardware and Software requirements
Laboratories – radiometry especially
Establish guidelines, policy, standards, and boiler plate
specifications
IADIWG involved in standards development & approval
IADIWG to begin specifying data “classes” in their work, requesting
USGS standards, educating users & industry
U.S. Department of the Interior
U.S. Geological Survey
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