USGS MIPS Deltav Documentation

USGS MIPS Deltav Documentation

This program is used to correct sonar images for variations in ship speed and spatial resolution differences in the along track versus across track directions(i.e., aspect ratio distortions). For example, the sonar imaging system may collect data in the across track direction(width) at 5 meters resolution however, the speed of the ship and the pulse repetition rate is such that the along track direction(height) resolution is 15 meters. This program will make the required adjustments so that the resolution is 5 meters in both directions.

Files

This program requires as input one unsigned 8-bit or signed 16-bit sonar image file and generates an output image of the same bit type. The following information is transferred from the input file to the output file(if appropriate):

Image labels
Sonar labels
Navigation file
History file

Note the input image must be a sonar image and have an associated navigation header file.

Parameters

PIXRES: This identifies the desired pixel resolution in the along track direction(the resolution is in meters per pixel and has no default value). Note, the program corrects only for the along track geometry/resolution; the program SLR2GR is used to correct/select the across track resolution --- both of these programs used together are required to get the square pixels.

Uses

This program is essential for correcting both aspect ratio distortions and variances in the ship's speed. Without these correction digital sonar mosaics will not have a constant ground resolution. Also, without the corrections the angle of linear features that are not exactly horizontal will be affected.

Examples

From left to right, slant range to ground range corrected sonar image without ship velocity corrections and the same sonar image with both corrections.

[Example Image]