IR process

Agriculture General Ag Questions/Troubleshooting
1

Is it possible to use the BSI formula in pix4Dfields??

BSI = ((Red+SWIR) - (NIR+Blue)) / ((Red+SWIR) + (NIR+Blue))** The Bare Soil Index (BSI) combines blue, red, near infrared (NIR), and short wave infrared (SWIR) bands to capture soil variations.

2

Yes, you can use the BSI formula in PIX4Dfields. To generate a custom index like BSI, follow these steps:

  1. Open the INDEX GENERATOR by clicking the icon at the top right of the window.
  2. Choose the source layer.
  3. Click “Create custom index” below the list of available indices.
  4. Name the index.
  5. Enter the formula: (Red + SWIR - NIR + Blue) / (Red + SWIR + NIR + Blue). You can do this by clicking the Operations and Available bands buttons or by using your keyboard. When the formula is valid, the Preview button will turn green.
  6. Click the Preview button to preview your index.
  7. When you are satisfied with the preview, click Apply.
  8. The generated custom index will now appear in the list of layers and in the map interface.

For more detailed instructions, you can refer to the comprehensive guide on generating vegetation indices in PIX4Dfields How to generate a vegetation index - PIX4Dfields

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The question will be if you have sensor which has the SWIR band. I only know that the sentinel satellite data has this, as in my screenshot.

3

Dear Julius,
thank you so much for the answer, glad to know that I can use BSI formula.
I did everything according to your instructions, but it won’t let me preview. Please check where the error is on the attached screen shot.
Thanks in advance.

Slika zaslona 2024-09-19 u 03.27.09.png
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čet, 19. ruj 2024. u 02:55 Julius Petri via Pix4D Community <notifications@pix4d.discoursemail.com> napisao je:

4

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You are trying to calculate the index with bands your sensor does not physically have. You have an RGB sensor it doesnt have neither NIR or SWIR. You can only use the satellite data and calculate it based on this data.

You the under “Available Bands” what bands you have, in this case its red, green and blue.

:artificial_satellite: To download satellite data in PIX4Dfields for your field, follow these steps:

  1. Import Images into a New or Existing Project :
  • For a new project, click New Project on the dashboard.
  • For an existing project, click Import on the layers menu.
  1. Select Download under the Satellite Data Section :
  • After the Import files menu appears, select Download under the Satellite data section.
  1. Select or Create a Boundary :
  • You can either select an existing boundary, create a new one by clicking Create new , or import a shape by clicking Import shape .
  1. Choose the Desired Images :
  • The prior month’s available images will appear in the graphic. The X-axis contains the date of each image, and the Y-axis contains the Cloud coverage bars and the average NDVI.
  • Click on the bars to display the image on the map.
  • Use the 14 days buttons on the sides to search images within those periods. Clicking the calendar icon allows you to select another month/year.
  1. Download and Create Layers :
  • To download an image, select it by clicking on the square above each bar. The selected days will appear on the right-hand side of the menu under Selected days .
  • Click Create layers to make them available in the layers menu of PIX4Dfields.

For more detailed guidance, you can refer to the full article Satellite data in PIX4Dfields