APPENDIX 5

Software for Plotting HydroSweep Multi-Beam Bathymetry Data

The Hydrosweep data are in a format given below. They may be plotted using software described in this appendix.

MBIO Data Format ID: Format name: Informal Description: Attributes:	5 MBF_HSATLRAW Raw Hydrosweep Hydrosweep DS, 59 beam, bathymetry and backscatter, ascii, Atlas Electronik.

So, first thing you have to do is to uncompress them. The command in UNIX is as follows:

% uncompress 9414hs.d* ( for a global uncompress of all the HS data)

Note: A compressed file is approximately 1/3 the original size. So you might want to make sure that you have enough disk space first.

A new release of the MB-System software is now available via anonymous ftp.

MB-System is a software package for Unix computing environments consisting of programs which manipulate, process, list, or display multibeam bathymetry and sidescan data. MB-System is being developed at the Lamont-Doherty Earth Observatory of Columbia University with support from the National Science Foundation, SeaBeam Instruments, and Antarctic Support Associates.

The new version, 4.1, replaces the previous release of version 3.4 in December, 1993. This release includes many improvements to the package. Among the most significant changes are:

- MB-System now handles sidescan as well as per-beam bathymetry and the associated beam amplitudes (the current generation of multibeam sonars all produce bathymetry, average beam amplitudes, and high resolution sidescan in a single data stream).

- MB-System now handles data formats with both acrosstrack and alongtrack distances for each bathymetry beam and sidescan pixel (vital for data from such sonars as the SeaBeam 2112 and the Elac Bottomchart).

- MB-System now handles shallow water data properly.

- MB-System now includes support for many new data formats, including:

SeaBeam SIO swathbathy format
SeaBeam 2000 SIO swathbathy bathymetry format
SeaBeam 2000 SIO swathbathy sidescan format
SeaBeam URI format in Vax byte order
Hydrosweep URI format in Vax byte order
HMR-1 processed data format
Simrad EM12 processed data from the RRS Darwin
Simrad EM1000 raw data
Elac Bottomchart UNB format
Reson Seabat 9001 UNB format


- The graphical tools (mbedit and mbvelocitytool) are now coded using the Motif widget set, giving the code greater portability. Xview based versions are still available for users hopelessly stuck on Sun workstations running under the old operating system.

- The macros (mbm_plot and mbm_grdplot) work better and generate more pleasing first cut plots.

- The gridding program (mbgrid) now allows both weighted mean and median filter gridding. The optional interpolation in regions with no data is now performed using the same minimum curvature algorithm developed by Walter Smith and Paul Wessel for the GMT program surface.

- The swath contouring program (mbcontour) now has two contouring algorithms. The first is the original "ping-to-ping" contouring approach which is fast but works poorly when nearby pings overlap. The new algorithm constructs a triangular network out of the bathymetry points and contours that with no assumptions about order in the data; this method is slower but produces better maps in many cases.

- Improved memory handling has greatly increased the reliability of programs such as mbswath and mbgrid.

- The program mbswath can generate swath color fill plots with shading derived from beam amplitude values.

- MB-System proper now consists entirely of code written in C (the realtime pen plotting code still depends on some Fortran77 routines).

- Many, many less prominent refinements and bug fixes.

ftp> cd pub/swath_data
ftp> binary
ftp> get README
ftp> get MB-System.4.1.tar.Z
ftp> get annual.Z
ftp> quit

To uncompress:
% uncompress *.Z

To extract the directory structure, move the MB-System tar file to a disk with at least 50 MBytes of free space and do the following:
% tar xvf MB-System.4.1.tar

Information and installation instructions are found in the file mbsystem/README.

There are some additional files available by anonymous ftp that may be of interest:

mbedit.xview.4.1.tar.Z
mbvelocitytool.xview.4.1.tar.Z
MB-SystemExamples4.0.tar.Z

The first two contain source code and fully linked executables for Xview (Sun SPARC) versions of two interactive graphical tools, mbedit and mbvelocitytool. The third contains some sample data files and example shellscripts demonstrating the use of some of the MB-System programs.

In the next few months, we expect our development effort will focus on the following issues:

- Adding a few additional data formats already requested

(SIO swathbathy Hydrosweep, raw HMR-1, raw Simrad EM12).

- Expanding the MB-System examples into a full, proper tutorial.

- Building a mouse driven GUI environment for most-used MB-System utilities.

- Developing or adapting sidescan mosaicing capability.

- Developing a navigation/heading/pitch/heave/roll data editor.

When corresponding, please email to both of us, as one of us is generally out of town or otherwise unavailable at any given time. We will do our best to be responsive to bug reports and suggestions for improvements.

Cheers,

Dave Caress and Dale Chayes

David W. Caress
SeaBeam Instruments
141 Washington Street
East Walpole, MA 02037
(also at Lamont-Doherty Earth Observatory)
caress@seabeam.com or caress@ldeo.columbia.edu
voice: 1-800-SEABEAM or (508) 660-6000
fax:(508) 660-6061

Dale N. Chayes
Lamont-Doherty Earth Observatory of Columbia University
Route 9W, Palisades, N.Y. 10964
dale@ldeo.columbia.edu
voice: (914) 365-8434
fax:(914) 359-6940