The Imagenex 881A Sector (imaging) and Profiling devices area multi-frequency digital scanning sonars.
http://www.imagenex.com/Products/881A/881A_Imaging/881a_imaging.html
http://www.imagenex.com/Products/881A/881A_Profiling/881a_profiling.html
We offer the following data formats on our Download Data page:
Daily 81A files
Separated Scan 81A files
Daily Space Delimited Text files
Separated Scan Space Delimited Text files
The space delimited text files are raw HEX format. They are for users who are familiar with these devices and have experience in data processing and analysis. In Separated Scan Space Delimited Text files, each scan is parsed out of the raw data and stored in its own file. For example, if a user requests Imagenex 881A Sector 3899 data on May 17 2008 and selects the Separated Scan Space delimited Text file format, the user will receive 24 files named like:
IMG881A3899_20080517_scan00.txt
IMG881A3899_20080517_scan01.txt
IMG881A3899_20080517_scan02.txt
IMG881A3899_20080517_scan03.txt
IMG881A3899_20080517_scan04.txt
IMG881A3899_20080517_scan05.txt
IMG881A3899_20080517_scan06.txt
IMG881A3899_20080517_scan07.txt
IMG881A3899_20080517_scan08.txt
IMG881A3899_20080517_scan09.txt
IMG881A3899_20080517_scan10.txt
IMG881A3899_20080517_scan11.txt
IMG881A3899_20080517_scan12.txt
IMG881A3899_20080517_scan13.txt
IMG881A3899_20080517_scan14.txt
IMG881A3899_20080517_scan15.txt
IMG881A3899_20080517_scan16.txt
IMG881A3899_20080517_scan17.txt
IMG881A3899_20080517_scan18.txt
IMG881A3899_20080517_scan19.txt
IMG881A3899_20080517_scan20.txt
IMG881A3899_20080517_scan21.txt
IMG881A3899_20080517_scan22.txt
IMG881A3899_20080517_scan23.txt
Here is an example of the HEX data in file IMG881A3899_20080517_scan06.txt:
20080517T060000.141Z 49 4d 58 10 41 01 01 05 00 00 7c 01 17 15 11 0b 06 07 0a 0c 0c 0b 08 03 02 04 05 05 04 04 04 05 04 03 02 04 07 0a 0b 0b 0a 09 06 03 03 02 02 02 02 01 00 01 01 02 02 02 02 02 02 01 00 02 03 04 05 05 05 05 05 04 04 03 04 04 05 06 07 08 08 08 08 07 07 07 07 07 07 07 06 06 06 07 08 0a 0c 0d 0d 0d 0d 0b 09 06 03 03 06 09 0b 0d 0e 0f 0f 0f 0f 0e 0e 0e 0f 0f 0f 0f 0d 0b 09 0a 0b 0d 0e 0e 0d 0c 0a 09 08 07 06 05 05 04 04 05 06 08 09 0a 0b 0a 09 07 05 04 08 0c 0f 12 13 13 12 0f 0b 06 01 03 05 05 04 03 06 09 0c 0e 0f 0f 0d 0b 08 04 03 07 0b 0d 0e 0d 0b 09 06 06 08 0a 0a 0a 09 08 06 05 05 04 03 02 04 07 09 0a 0a 09 07 03 03 08 0b 0d 0d 0c 0a 07 04 03 06 08 0a 0b 0c 0c 0b 0a 07 04 02 02 03 03 01 02 06 0a 0e 11 13 15 15 15 13 11 0e 0b 08 06 04 03 02 02 03 03 03 04 04 05 06 07 07 07 07 06 7f 26
20080517T060001.150Z 49 4d 58 10 41 7e 00 05 00 00 7c 01 03 03 03 04 05 06 07 07 08 08 09 09 08 08 07 06 05 03 02 03 05 07 09 0a 0a 0b 0b 0a 0a 0a 0a 09 09 08 07 04 04 03 05 06 08 09 09 0a 09 09 08 07 05 05 05 05 06 05 05 04 03 03 02 03 03 04 05 06 07 08 08 08 08 07 06 04 02 03 05 05 05 04 03 06 0b 0f 13 16 16 16 15 12 0e 0a 06 03 01 02 03 06 09 0c 0f 10 12 12 11 10 0e 0b 08 04 04 09 0e 13 17 19 19 17 13 0e 09 08 0c 0f 12 14 15 15 15 13 11 0f 0c 09 06 06 08 0a 0c 0c 0c 0b 0a 09 09 0a 0b 0c 0d 0e 0e 0e 0d 0c 0b 0a 0a 0b 0b 0c 0d 0e 10 11 11 12 12 12 12 11 10 0e 0c 0a 07 04 03 05 08 0b 0d 0e 0e 0e 0e 0c 0b 09 07 06 05 05 06 06 06 06 05 04 04 05 06 06 05 04 01 04 09 0c 0f 11 12 13 12 11 0f 0d 0a 08 05 03 01 03 04 05 05 05 05 04 03 02 02 03 04 04 05 04 04 04 04 04 05 06 08 09 0a 0a 0a 0a 08 07 06 05 7f 26
Daily Space Delimited Text files are in the same HEX format, but all the scans are in one file. If a user requests Imagenex 881A Sector 3899 data on May 17 2008 and selects the Daily Space delimited Text file format, only one file (IMG881A3899_20080517_daily.txt) will be returned.
81A files are the manufacturer’s native data format and readable by the software program win881A.exe (downloadable from the Imagenex website http://www.imagenex.com/Downloads/downloads.html). Daily 81A files contain all the data collected in one day and the scans are parsed out in Separated Scan 81A files – just like the text files with .81A extension. Here is a snapshot of Imagenex Sector 3899 data displayed using the win881A software:
