mbswplspreprocess
Section:  MB-System 5.0  (1)
Updated:  26 March 2014 
Index


 
NAME

mbswplspreprocess - prepairs a SWATHplus sonar file (MBIO 
format 222) for processed with MB System.                             
 
VERSION

Version 5.0

 
SYNOPSIS

mbswplspreprocess [-ABGNRSHV] [-Fformat] 
[-Jproj4command] [-Ooutfile] -Ifile

 
DESCRIPTION

mbswplspreprocess prepairs a SWATHplus SXP (MBIO format 222) 
file for processing with MB System. 


MB System can read and plot SXP files 
without modification. However, many of the editing and calibration programs 
work best if each transducer channel is stored in a separate file (use 
the -S option). In particular, multiple transducer channels pinging 
simultaneously will trip up time filtering, since each channel in the 
ping series has the same time stamp.                                  


If during data acquisition using the SEA SWATH Real-Time Acquisition System 
(SEA Swath Processor), the "Store All Data" option was selected in combination 
with the "Downsample" Bathy filter, the SXP ping records will contain 
both the original data (all samples rejected) and the filtered data (all 
samples accepted) simultaneously. This will confuse most programs in MB 
System. Use the -B and -R options as needed to strip out 
the undesired set prior to processing.                                


SXP ping records contain both a raw amplitude and a processed amplitude 
value for each sample. MB System reads and writes ONLY the processed amplitude 
values, leaving the raw values untouched. Use the -A option to 
copy (or restore) the raw amplitude values into the processed amplitude 
slots so that they can be accessed by MB System.              

 
MB-SYSTEM AUTHORSHIP

David W. Caress




  Monterey Bay Aquarium Research Institute



Dale N. Chayes




  Center for Coastal and Ocean Mapping




  University of New Hampshire



Christian do Santos Ferreira




  MARUM - Center for Marine Environmental Sciences




  University of Bremen

 
AUTHORSHIP OF THIS PROGRAM

David P. Finlayson




  Formerly at Pacific Coastal and Marine Science Center, USGS



 
OPTIONS


-A





This option causes the program to copy the raw amplitude values stored 
with each sample into the corresponding processed amplitude slot where 
it can then be used by MB System.
-B





This option causes the program to reverse the sample flag setting. That 
is, rejected samples become accepted samples and vis-a-vis. This option 
is always applied before option -R.                 
-F


format



Sets the data format used if the input is read from stdin or from a file. 
If format < 0, then the input file specified with the -I 
option will actually contain a list of input swath sonar data files. This 
program only reads Bathyswath (SWATHplus) format data files (MBIO 
format 222).                                                                                                          
-G


Print to stdout an ASCII representation of each data record read from the file.
-H


This "help" flag cause the program to print out a description
of its operation and then exit immediately.
-I


infile



Sets the input file path. If format > 0 (set with the
-f option or mbdefaults) then the swath sonar data contained in infile
is read and processed. If format < 0, then infile
is assumed to be an ascii file containing a list of the input swath sonar
data files to be processed and their formats.  The program will read
the data in each one of these files.
In the infile file, each
data file should be followed by a data format identifier, e.g.:

        datafile1 222 1


        datafile2 222 1




This program only reads SWATHplus format data files (MBIO format 
222). .                                                               
-J


projection



The SWATHplus software packages operate with navigation in a user-defined
projected coordinate system.  Resultantly, SXP format files contain
positions in a projected coordinate system rather than longitude and
latitude in geographic coordinates.  Generally, the SXP files do not contain
any description of the projection used to obtain the eastings and northings
in those files.  This option allows a user to specifiy the projection used
to translate the eastings and northings back into longitude and latitude. 
If this option is not specified, MB-System will assume the data are
associated with UTM zone 1 north.  The projection identifier must conform to
the same usage as with projections specified for mbgrid.  For
instance, to fully specify a particular northern UTM zone, set projection =
UTMXXN where XX gives the UTM zone (defined from 01 to 60).  As an example,
a northern UTM zone 12 projection can be specified using -JUTM12N.  Southern
UTM zones are specified as UTMXXS.  The European Petroleum Survey Group
(EPSG) has defined a large number of PCS's used worldwide and assigned
number id's to each; one can also specify the northern UTM zone 12
projection using its EPSG designation, or -Jepsg32612.  The complete list of
projected coordinate systems supported by MB-System is given in the mbgrid
manual page.
-N


Do not write output file. Useful for inspecting files, especially combined 
with -G.
-O


outfile



This option causes mbswplspreprocess to output all data to a single file
specified as outfile. By default, the program creates output files for
each input file. If combined with -S, this will serve as the basename
for a set of output files, one for each transducer.
-R


This option removes all rejected samples from pings before writing output.
-S


This option saves each transducer channel into a separate output file. This is
the best way to handle simultaneous pinging in MB System and the only way to
handle 3 or more transducer channel systems. The transducer channel will
be appended to the output filename as follows:



outfile_txer<channel>.mb222

 
EXAMPLES

Suppose that one has collected a SWATHplus datafile incorporating interferometric 
sonar data from a 2-transducer system pinging simultaneously. The file name 
is:


20140418_150155.sxp





To split each transducer into its own file for better filtering support 
from MB System, to reset the amplitude values to their original pre-processed 
values, and to strip out any previously flagged data run:


mbswplspreprocess -SAR -I20140418_150155.sxp





To export the data records stored in an SXP file to a text file:


mbswplspreprocess -GN -I20140418_150155.sxp > output.txt





 
NOTES

The SXP file format does not contain sufficient information to completely re-process 
the data in MB System itself. For example, you should not attempt to re-calculate 
bathymetry based on new sound velocity information. Ridged translations and
rotations are OK (static shifts in x, y, or z, rotations about the transducer reference point) 
provided that each transducer channel resides in its own file (see the -S option). It is 
always safe to edit and filter the soundings in mbedit and mbeditviz.                         


SXP files use a projected coordinate system for all transducer and sea 
floor sample coordinates. The user must supply a .PRJ file defining the 
coordinate system (usually UTM) for each input file before proceeding 
with further processing in MB System. The coordinate system is not stored 
in the SXP file data itself.                                          
 
SEE ALSO

mbsystem(1), mbformat(1), mbinfo(1)

 
BUGS

Oh yeah.



 
Index

NAME

VERSION

SYNOPSIS

DESCRIPTION

MB-SYSTEM AUTHORSHIP

AUTHORSHIP OF THIS PROGRAM

OPTIONS

EXAMPLES

NOTES

SEE ALSO

BUGS