GeoExpress Case Study – City of Rockville, MD

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City Uses GeoExpress Floating Licenses to Enable Team Access to Image Processing

Background

Rockville, MD, is a city of about 57,000 that owns a significant portion of its utilities. The city maintains thousands of engineering drawings generated in the development of those utilities and in capital improvement projects so that other city employees can use them online. GeoExpress enables them to process, store and access these records with greater flexibility and efficiency.

Challenges

Just northwest of Washington, D.C., the City of Rockville, Maryland, maintains its own water, sewer and storm drain utilities. It also reviews plans for new development and for capital improvement in accordance with the city’s design standards. In all, the City of Rockville preserves a catalog of more than 8,500 original records dating as far back as the 1940s for viewing online and printing.

To preserve and extend the usefulness of these documents — typically paper or mylar drawings measuring 24”x36” — Rockville scans them to TIFF images using a large-format scanner. Originally all documents, whether color or grayscale, were scanned at 1 bit per pixel for more efficient use of storage space, quicker transfer over networks and easier online access.

But while 1-bit scanning reduced file sizes, it made preserving color or even grayscale drawings impossible and sacrificed considerable image detail. Plus, the resulting image files did not display very well in the city’s many installed ArcView 3.2 viewers.

Retaining Both Image Quality and Access Efficiency
Rockville’s GIS office was looking for a way to reduce the file size of scanned engineering drawings without sacrificing color or detail, in a file that would transfer quickly and render properly in their legacy viewers.

“People are going to be looking at these documents on computer screens and also downloading them for printing,” says Marc Weinshenker, Rockville’s GIS manager. “We wanted to make sure we retained the image quality attributes they would need in both situations.”

Distributing the Image Processing Workflow
“A few years ago we installed GeoExpress,” says Weinshenker, “and at that point I became the sole employee doing image compression and processing. The results were great, but I wanted everyone to be able to share in the image processing workload.”

Solution

GeoExpress networked data cartridge made it possible, with the purchase of an additional license, for other employees to use the software on a computer designated for that purpose. However, having to move away from their workspace to use a different computer proved inconvenient for employees. The city’s budgets couldn’t accommodate a license for everyone who would possibly use the software. What Rockville needed was the floating license capability and License Manager introduced in 2006 in GeoExpress 6.0.

The floating license enables Rockville to install GeoExpress on the local machine (client) of any team member who may need to perform image processing or compression, no matter how infrequently. The License Manager then distributes a temporary license to a particular client at the time of use, allowing multiple simultaneous users up to the number of purchased licenses.

The MrSID® wavelet-based technology underlying GeoExpress offers efficient compression without loss of image quality. The City of Rockville can now preserve color information at its full 24 bits per pixel for an average file size of only 6MB in MrSID format, whereas the same file would measure 100MB uncompressed. Similarly, grayscale images preserved at the full 8 bits per pixel go from an average of 33MB uncompressed to just 2MB as MrSID files.

Benefits

Greater Flexibility and Efficiency in Image Processing
“GeoExpress originally met our needs in terms of image quality, optimizing the use of our storage space, and compatibility with the tools we’re using,” says Weinshenker. “But the new benefit for us with version 6.0 is being able to run GeoExpress on a number of different clients using the new License Manager — that represents a big improvement in flexibility and productivity for us.”

Greater Value in Smaller Files
The City of Rockville now serves color and grayscale versions of its documents with all image detail preserved and at greatly reduced download times.

Easier Viewing Online
MrSID images display better than 1-bit TIFFs in Rockville’s legacy GIS viewers, and the smaller file sizes make transfer time and download much quicker for the city’s GIS users.

GeoExpress made the City of Rockville’s image processing workflow more flexible and enabled them to use storage resources more efficiently and deliver a better viewing experience for online users.