Setting the Aspect Ratio of SBP images during batch image export

It is useful to control the horizontal and vertical resolution of sub-bottom profile images exported from SonarWiz. For example, if you want to ensure that a profile image will be no more than 1000 pixels across and have a 10:1 vertical exaggeration, you need to set the horizontal and vertical resolution appropriately.

In general, you need to proceed in four steps:

1. Find the length of your longest profile in map units (meters or feet)

2. Set the horizontal scale so that your exported images will be the appropriate width.

3. Set the vertical scale to control the desired vertical exaggeration of the images.

4. Export the group of images

Step 1: Find the length of the longest profile:

The Project Summary report lists the length of all of the profiles in the project. This will allow us to quickly find the length of the longest profile in the project:

1. Right Click the Sub-bottom Files branch in the Project Explorer and select Project Summary Report.

2. Look for the Line Length column in the report and identify the longest line in the project
   
   

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   In this example, the longest line is 1449.6 m

Step 2: Determine the Horizontal Scale of the output image

To set the horizontal scale of the output image so that it just fits into a report or CAD system. You will need to know the maximum number of pixels across you need the image. For example, this help file works best with images that are 800 pixels across. Use the following formula to compute the horizontal units/pixel needed:

horizontal units/pixel = (width of profile) / (maximum width of output image in pixels)

for our example:

1.812 m/pixel = 1449.6 m / 800 pixels

To set the horizontal scale:

1. Click the green Options button on the upper-left side of the SonarWiz title bar to open the Preferences and Settings dialog.

2. Select SBP Options

3. In the Horizontal Profile Image Resolution (post-processing) group, select Speed Corrected and set the units/pixel value. In our example, I set the horizontal resolution to 1.812 as calculated above.
   
   

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Step 3: Determine the Vertical Scale of the output image

To set the vertical scale of the output image, first determine how much vertical exaggeration you want the image to have. Then use the following formula to compute the vertical units/pixel value:

vertical units / pixel = (horizontal units per pixel) / (vertical exaggeration)

In our example, we will use 10:1 Vertical Exaggeration (VE) so:

0.1812 = 1.812 / 10

To set the vertical scale:

1. Click the green Options button on the upper-left side of the SonarWiz title bar to open the Preferences and Settings dialog.

2. Select SBP Options

3. In the Vertical Profile Image Resolution (export only) group, select User Specified and set the Units/pixel value. This sets the vertical scale of the image.
   
   
   

Step 4: Batch Export the images

Now that the horizontal and vertical resolution are set, you can proceed to export all of the profiles using the same scale and vertical exaggeration.

To Batch Export the Images:

1. Right Click the Sub-bottom Files branch in the Project Explorer and select the Batch Image Export command.

2. Set any image Options you want to enable/disable

3. Select the files to export

4. Click OK

Here is the result of my example

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