Title: Creating data delivery services from catalogue searches
1Creating data delivery services from catalogue
searches
- Dr Matt Pritchard
- NERC Earth Observation Data Centre (NEODC)
- http//www.neodc.rl.ac.uk
- CCLRC Rutherford Appleton Laboratory, UK
2Introduction
- QMASS
- NERC Earth Observation Data Centre (NEODC)
- NEODC LANDSAT service
- NEODC ATSR service
3Talk outline
- Overview of services
- Development details
- Search and present in SSE services
- Spatial searching
- Future plans
- Comments
4Overview of services
5LANDSAT Service
6LANDSAT Service
7LANDSAT Service
8LANDSAT Service
9LANDSAT Service
10Overview of services
11ATSR Service
12ATSR Service
13ATSR Service
14ATSR Service
15ATSR Service
16ATSR Service
17ATSR Service
18Talk outline
- Overview of services
- Development details
- Search and present in SSE services
- Spatial searching
- Future plans
- Comments
19Search and Present in SSE services
NEODC Metadata catalogue
SearchInputMsg
SearchOutputMsg
20Search and Present in SSE services
- Search
- processSearchInputMsg sent from Portal
- Encodes coordinates, collectionId,
- Create db connection
21Search and Present in SSE services
- Search
- Convert parameters to SQL string
- summary presentation format
- Stylesheet Search2SQL.xsl
processSearchInputMsg
22Search and Present in SSE services
23Search and Present in SSE services
- Search
- Search script invoked to handle result
- Summary presentation -gt summaryScript.xml
- summary / brief / browse / full
- Creates processSearchOutputMsg
24Search and Present in SSE services
- Search
- GML footprints for display on Portal AOI tool
- processSearchOutputMsg
- Catalogue2GML.xsl
- GML file
25Search and Present in SSE services
- Present
- Single item, more detail
- Full presentation format -gt fullPresentScript.xml
26Talk outline
- Overview of services
- Development details
- Search and present in SSE services
- Spatial searching
- Future plans
- Comments
27Spatial searching
- Spatial databases
- Geometric datatypes
- geometry
CREATE TABLE mytable ( ... myfield
geometry, ... ) INSERT INTO mytable (myfield)
VALUES( 'SRID4326POLYGON(( 38.49
-3.37, 40.68 -3.37, 40.68 -5.28, 38.49
-5.28, 38.49 -3.37 )) )
28Spatial searching (PostGIS)
- Geometric comparison operators
- (overlaps)
- _at_ (contains)
select myfield from mytable where myfield
GeometryFromText('BOX3D(30 0, 40
-10)'box3d,4326) SRID4326POLYGON((38.4958795
-3.376287,40.6831798 -3.374955,40.6874065
-5.2848047,38.4946129 -5.2868938,38.4958795
-3.376287)) (1 row)
select myfield from mytable where dsgpolyo
GeometryFromText('POLYGON((0 0, 40 0, 40 -10, 0
-10, 0 0))',4326) SRID4326POLYGON((38.4958795
-3.376287,40.6831798 -3.374955,40.6874065
-5.2848047,38.4946129 -5.2868938,38.4958795
-3.376287)) (1 row)
29Spatial searching (PostGIS)
- Geometric functions
- xmin(geometry)
- transform(geometry, srid)
select xmin(myfield), ymin(myfield),
xmax(myfield), ymax(myfield) from mytable where
myfield GeometryFromText('BOX3D(30 0, 40
-10)'box3d,4326) xmin ymin
xmax ymax 38.4946129 -5.2868938
40.6874065 -3.374955 (1 row)
select xmin(transform(myfield,27700)) from
mytable where myfield GeometryFromText('BOX3D(3
0 0, 40 -10)'box3d,4326)
xmin 5307661.95830263 (1 row)
30Spatial searching (PostGIS)
Polygon C westbc 175 eastbc -175 northbc
75 southbc 70 (westbc gt eastbc) Blue
AOI westbc -10 eastbc 10 northbc 75 southbc
70
31Spatial searching (PostGIS)
- Longitude180 problem
- False positive for polygon that does not exist
PostGIS http//postgis.refractions.net PostgreSQL
http//www.postgresql.org
32Spatial searching
- PgSphere
- PostgreSQL extension
- Spherical geometry
- spoly
CREATE TABLE myTable ( ... myField spoly,
... ) INSERT INTO mytable (spoly) VALUES( '
(160d,75d), (170d,75d), (170d,70d), (160d
,70d), (160d,75d) ')
33Spatial searching (PgSphere)
- Geometric comparison operators
- (overlaps)
- _at_ (contains)
select id, myfield from mytable where myfield
sbox '((165d,65d),(173d,73d))' id myfield A
"A""(2.792 , 1.308),(2.967 , 1.308),(2.967 ,
1.221),(2.792 , 1.221)" (1 row)
select id FROM mytable WHERE myfield _at_ sbox
'((160d,65d),(-170d,76d))' id A C (2 rows)
34Spatial searching (PgSphere)
- Spherical geometry
- Correct result
- PgSphere
- http//www.pgastro.org/cgi-bin/wiki.pl?pgSphere
select id FROM mytable WHERE sbox
'((-10d,70d),(10d,75d))' p id (0 rows)
35Talk outline
- Overview of services
- Development details
- Search and present in SSE services
- Spatial searching
- Future plans
- Comments
36Future plans
- Future plans
- ATSR -gt AATSR
- Airborne geocorrection
- NEXTMap DEM
- User rights
- NEODC account login
- Other methods (x509 certificates?)
37Talk outline
- Overview of services
- Development details
- Search and present in SSE services
- Spatial searching
- Future plans
- Comments
38Comments
- TOOLBOX
- XML scripting language
- Context in which each tag will/will not work
- Script schema?
- Jelly XML?
- Portal
- Upgrades
- Notice of downtime / essential upgrades
- Existing / future services
- Backwards compatibility
- Security
- User rights management