ngEO Browse Server

ngEO Architecture

BROW Architecture

Flow of Browse Images

Ingestion of Browse Images

Preprocessing

• Input Geographic Metadata for Geo-referencing
  • Footprint polygon - footprint
  • Regular grid of tiepoints - regularGrid
  • Pre-georeferenced images
  • rectifiedBrowse
  • modelInGeotiff
• Optimizations
  • Footprint generation
  • Re-projection
  • Addition of alpha-channel
  • Internal tilling
  • Overviews
  • Compression

Retrieval of Browse Images

BROW Components

BROW Component Core

BROW Core Data Model

Technology Baseline

• CentOS 6 64bit repositories (base, extras, updates) based on RHEL 6
• Apache HTTP server 2.2: httpd, mod_wsgi
• PostgreSQL 8.4: postgresql-server, postgresql
• Python 2.6: python, python-lxml, python-psycopg2, pytz
• EPEL & ELGIS repositories
• Django 1.4: Django14
• PROJ.4 4.8: proj
• GDAL 1.9: gdal, gdal-python
• PostGIS 1.5: postgis
• EOX repository
• libxml2 2.7: libxml2, libxml2-python - GML patch
• MapServer 6.2: mapserver, mapserver-python - 6.0 otherwise
• MapCache 1.2; 1.3dev: mapcache
• EOxServer 0.3.1; 0.3dev: EOxServer
• ngeo.b.core 1.0.2; 2.0dev: ngEO_Browse_Server

Development & Testing

• Git hosted on GitHub
• Vagrant & VirtualBox (see HOWTO)
• Jenkins CI
• Python/Django unit test framework
• Performance tests using JMeter
• Integration testing on OpenStack platform provided by Task 5

BROW Deployment Basic

BROW Deployment Multiple

BROW Deployment Alternative

BROW Installation

Changes

• Tile merging limit per tile instead of per browse layer (demo)
• Merge images during ingestion (S1)
• Asynchronous seeding
• Faster synchronous part for FEED
• Synchronization between BROW components/Consistency checks
• Improved performance in case of merging
• Delay in availability on WEBC

Security

• Authentication using Shibboleth
  • BROW Deployment Recommendation
  • Separate instances for Open and Protected browse layers
  • Pro: Far easier configuration of Shibboleth e.g. redirects
  • Con : Small operations overhead
• Authorization
  • Alternative 1: ngEO-CP
  • Harmonization in ngEO
  • Depending on design and implementation
  • Alternative 2: BROW Custom
  • Middleware in MapCache calling simple tool using memcached to obtain decision

Communication with CTRL

• Done
  • Register/Unregister
  • Status
  • Log
• To be done
  • Global and specific configuration
  • Additional parameters e.g. max number for tile merging, default time interval in WMTS
  • Pause/Resume/Stop/Restart
  • Notifications
  • Reporting

Status

• V1
  • Finished 6 months ago
  • Waiting for final closure
• V2
  • Finished sprint 1 and parts of 2
  • Continued once V1 is closed
• Sidestep Task 5
  • ngEO-MM Reference Platform
  • Current status
  • Datasets: Landsat TM & ERS
  • Issues reported to Jira e.g. NGEO-926, NGEO-927, NGEO-928, NGEO-940