About GP4 Files.doc

About GP4 Files

What is a GP4 file?

Many of the files in the Region 9 Digital Library contain a GP4 file extension. Files with a GP4 extension are scanned raster images of manual drawings.

For centuries architectural drawings were done on various flat lightweight media, such as linen, paper, vellum or mylar. These drawings were drawn by hand and are referred to as manual drawings. Before the advent of scanning technology and raster images these drawings were only available as hardcopies. It's more common today to use computer aided drafting software like AutoCAD to produce AE drawings. These files are already in an electronic format and don't need to be scanned. The CIFM Team does still scan AE project drawings that are not done using CAD; for example a marked up set of as-builts or shop drawings.

A file must be in electronic format for it to be incorporated in the Region 9 Digital Library.

So what is a scanned raster image? GP4 files are RASTER (composed of a series of dots with no specific beginning or end) files. A CAD file is a VECTOR (composed of lines, arcs and circles with a specific beginning and ending point) type file.

Using current technology a manual drawing can be scanned to produce a digital image. The digital information from the scan is placed in an electronic file. The digital file format used by PBS is GP4.

· A viewer or software program that can read a GP4 file is required in order to view and or plot the file. PBS utilizes VoloView to accomplish this.

GP4 files can also be viewed using AutoCAD 2000 - 2007. Open AutoCAD, Go to INSERT and open the drop down menu. Select RASTER IMAGE, then click the ATTACH button. Locate the GP4 file you wish to view. Click on the AutoCAD HELP for more information.

If you do not have a software program that can read a GP4 file, you will not be able to view or access the file.

If you want to know more about GP4 files please refer to the Internet.

Frequently Asking Questions about GP4 files.

1) Is a GP4 file a CAD file? No. A CAD file is a VECTOR (composed of lines, arcs and circles with a specific beginning and ending point) type file and GP4 files are RASTER (composed of a series of dots with no specific beginning or end) files. Please consult the Internet for more information regarding the differences between VECTOR and RASTER files. Please note that it is possible to insert, import and paste certain types of RASTER files into CAD files, refer to your CAD manual for details.

2) Why doesn’t the GSA have CAD files of buildings built around the turn of the century? AutoCAD did not come into wide use until the mid-eighties. All architectural drawings done before that time were drawn manually, not electronically using CAD software. If the building has undergone a recent renovation there may be a good set of CAD files.

3) Why is it that buildings due for major renovations always have the worst set of incomplete drawings and no CAD files whatsoever? This is a comment that the CIFM Team receives often. There could be several reasons all of which are beyond the Teams control, such as: the building was designed before CAD was the standard for creating construction drawings; many of the original drawings have been lost, misplaced or damaged due to constant handling; the drawings are somewhere in someone's desk or drawer and have never been forwarded to the CIFM Team for incorporation in the Region 9 Digital Library.

4) I noticed many of the GP4 files have file names that do not conform to the most recent National Cad/CIFM Standards. Why is that? Files that are indexed and archived in the REGION 9 DIGITAL LIBRARY have their own unique file naming system. This clearly identifies the file as having been indexed and in the Library. For more information about file naming refer to the most recent National Cad/CIFM Standards.

5) What is the advantage of using GP4 files?

a) Electronic files can be e-mailed.

b) Electronic files can be manipulated and converted to CAD files (with the appropriate software, refer to the Internet).

c) Hundreds, if not thousands, of GP4 files can be placed on one CD.

d) GP4 files can be used as backgrounds in CAD drawings.

e) Ultimately both the GSA and the AE firms save money by not plotting, and or copying, hundreds of unnecessary drawings.

f) GP4 files are electronic files that can be incorporated into the Region 9 Digital Library.

g) Finding drawings using the Digital Library is much faster than thumbing manually through piles of hard copy.

h) PBS has an electronic copy of the manual drawing as a permanent record.

i) There is less chance the hardcopy originals will be lost, misplaced or damaged because the GP4 files are used instead.