DRAPP08 – March MeetingDRAPP08 – March Meeting

Welcome and Introductions (Matt)

Agenda:

• Communications Plan Overview (Gabe)• File formats and examples (Matt)• RTD’s Interactive System Map –use of a WMS (Dan

Jackson):• Business-related items (Paul)• Next Meeting: April 23rd at 1:30 pm• Adjourn

DRAPP08 – March MeetingDRAPP08 – March Meeting

• News!– Final panel placement is being done by

the DAT and Acquisition vendors (as we speak)

– BHI/Surdex are routing their aircraft (2) to Denver as we speak …

– Non-member funding totals are close to the $100K (initial) goal• Let others know please!!!

DRAPP08 – March MeetingDRAPP08 – March Meeting

• Communications Plan Overview (Gabe)

DRAPP08 – March MeetingDRAPP08 – March Meeting

• File formats and examples (Matt)– SP vs. UTM for tiles

•For the UTM versions, translate 1 foot to 0.3 meters and ½ foot to 0.15 meters

•Have to stop the tile boundaries on an even pixel, so they will be just a little different in size.

• BHI Web Map and DRAPP Website are good sources for updates/downloads– http://www.drcog.org/drapp

DRAPP08 – March MeetingDRAPP08 – March Meeting

• File formats and examples continued …– Overlap is 20 feet on all tiles on each side

– Total = 40 feet of overlap between tiles• The UTM versions will be something nearly identical. Less overlap

means smaller files and fewer problems (warped bridges, skyscraper lean, etc.) that span two tiles, which have to be fixed twice in Photoshop.

– Overlap and DB issues• BHI used to do 50ft, NCTCOG in 2003 put imagery into ArcSDE, BHI

does not use ArcSDE but uses the NCTCOG project as a baseline.• USGS DOQQ’s are typically up to 300m overlap so they are a

special case of a lot of overlap.

– BHI color balancing software finds that 20ft is sufficient to get a good continuous color balance across tiles.

• At least 1 pixel of overlap is required to keep some GIS software from showing or printing white lines between tiles due to re-sampling imperfections.

DRAPP08 – March MeetingDRAPP08 – March Meeting

• File formats and examples continued …– File sizes for all formats include:RGB+I 6" GeoTIFF

RGB+I 1' GeoTIFF

RGB+I 6" TIFF w/JPEG

RGB+I 1' TIFF w/JPEG

RGB+I 6" MrSID

RGB+I 1' MrSID

RGB+I 6" JPEG2000

RGB+I 1' JPEG2000

DRAPP08 – March MeetingDRAPP08 – March Meeting

• 4-bands ‘packaged’ for ArcGIS– What does this look like?

DRAPP08 – March MeetingDRAPP08 – March Meeting

• The 4 band option saves 1/3rd space over having two 3 band images, we are doing what Denver did in ’06 as a post-process step with the vendor– CAD software may struggle with this, volunteers to test?

• RGB is red, green, blue - CIR is infrared– R and G from the RGB are not the same red and green

from the CIR– Due to folks’ software constraints vendor needs to do a

color balance of the RGB and the CIR images separately to make them look pleasing to the eye

– During that process the two sets of red and green bands get altered differently, and their histograms are divergent

DRAPP08 – March MeetingDRAPP08 – March Meeting

• RTD WMS example– Dan Jackson!

DRAPP08 – March MeetingDRAPP08 – March Meeting

• Other Biz???– Paul Gibbs, DRCOG

• Next DRAPP meeting: April 23rd