Step 4. Processing - PIX4Dmapper

Follow

Index  Previous  |  Next 

This article will list the recommended steps to go through when processing a project.

The recommended steps include:

  1. Initial Processing
  2. Analyzing the Quality Report
  3. Point Cloud and Mesh 
  4. DSM, Orthomosaic and Index

1. Initial Processing

To start processing the project:

1. On the Menu bar, click View > Processing.

Menu bar View Processing in PIX4Dmapper  

2. The Processing bar opens at the bottom of the main window.

Processing bar 1. Initial Processing in PIX4Dmapper

3. Ensure that 1. Initial Processing is selected, and that 2. Point cloud and Mesh and 3. DSM, Orthomosaic and Index are unselected:

Processing bar 1. Initial Processing Start in PIX4Dmapper

4. Click Start.

 

2. Analyzing the Quality Report

 
Important:
  • For a detailed description of how to analyze the Quality Report: Quality Report Help.
  • For a detailed description of any parameter described in the Quality Report: Quality report specifications.
  • An example of a Quality Report is available as an attachment.

Once step 1. Initial Processing is completed, the Quality Report is automatically displayed. To not be displayed automatically, unselect the Display Automatically after Processing box at the bottom of the Quality Report. 

When more than one step is processed sequentially, the PDF Quality Report is generated in the results folder only when the processing is completed. However, it is automatically displayed in Pix4Dmapper once a step is completed.

It is recommended to verify the following information in the Quality Report:

1. Quality Check

Verify that:

  • All the checks are green.
  • All or almost all the images are calibrated in one block
  • The relative difference between initial and optimized internal camera parameters is below 5%.
  • (optional) If using GCPs, the GCP error is below 2×GSD.

Quality check table in PIX4Dmapper

 

2. Preview

For projects with nadir images and for which the orthomosaic preview has been generated, verify that the orthomosaic:

  • Does not contain holes.
  • Does not have distortions.
  • (optional) If GCPs or image geolocation has been used, it has the correct orientation.

 Orthomosaic Preview in PIX4Dmapper quality report

 

3. Initial Image Positions

(optional) If the images have geolocation, verify that the Initial Image Positions figure corresponds to the flight plan.

Quarry Orthomosaic Preview in PIX4Dmapper quality report

Quarry Orthomosaic Preview in PIX4Dmapper quality report

4. Computed Image/GCPs/Manual Tie Points Positions

Verify that :

  • (optional) If using images with geolocation, the computed image geolocation is good.
  • (optional) If using only images with geolocation, the uncertainty ellipses are similar in size.
  • (optional) If using GCPs, the GCPs' error is low (the difference between input and computed GCPs is small).
  • (optional) If using GCPs and images with geolocation, the uncertainty ellipses are very small, close to the GCPs and may increase for images further away.

Computed Image GCP MTP Positions in PIX4Dmapper

Computed Image GCP MTP Positions in PIX4Dmapper

 

5. Absolute Camera Position and Orientation Uncertainties

Verify that:

  • For projects only with image geolocation, the absolute camera position uncertainty is similar to the GPS accuracy, and that the sigma is smaller than the mean.
  • For projects with GCPs, the absolute camera position uncertainties are similar to the accuracy of the GCPs.

 absolute camera position and orientation uncertainties table in PIX4Dmapper quality report

6. 3D Points from 2D Keypoints Matches

Verify that:

  • Enough matches have been computed between the images.
  • The graph consists of one block. If multiple blocks exist, each block will have a different color.
  • The uncertainty ellipses are approximately of the same size throughout the project. 

2D Keypoints Matches graph in PIX4Dmapper quality report

7. Geolocation Details

(optional) If using GCPs, verify that:

  • All GCPs are considered (not displayed with red color on the Geolocation and Ground Control Points table).
  • All marked GCPs have been verified.

 Ground control point GCP table in PIX4Dmapper quality report

8. Processing Options

Verify that:

  • (optional) If using GCPs, the Ground Control Point (GCP) Coordinate System is correct.
  • (optional) If using images with geolocation, the Image Coordinate System is correct.

 System information in PIX4Dmapper quality report

 Coordinate system information in PIX4Dmapper quality report

 Processing option information in PIX4Dmapper quality report

 

3. Point Cloud and Mesh

To process step 2. Point Cloud and Mesh:

1. On the Menu bar, click View > Processing.
2. The Processing bar opens on the bottom of the main window.
3. Ensure that 2. Point Cloud and Mesh is selected, and that 1. Initial Processing and 3. DSM, Orthomosaic and Index are unselected.

Processing bar 2. Point Cloud and Mesh in PIX4Dmapper

4. Click Start.

 

4. DSM, Orthomosaic and Index

To process step 3. DSM, Orthomosaic and Index:

1. On the Menu bar, click View > Processing
2. The Processing bar appears at the bottom of the main window.  
3. Ensure that 3. DSM, Orthomosaic and Index is selected, and that 1. Initial Processing, and 2. Point Cloud and Mesh are unselected.

Processing bar 3. DSM, Orthomosaic and Index in PIX4Dmapper

4. Click Start.

 

Index  Previous  |  Next 
Was this article helpful?
21 out of 32 found this helpful

Article feedback (for troubleshooting, post here instead)

2 comments

  • Sing Sithnalong

    Hi technical support,

    Do you know how to put tile point to the red one (uncalibrated camera )?

    Thanks

     

     

  • Teo (Pix4D)

    Hi Sing,

    Firstly, you need to ensure that all images get calibrated. There may be a lot of reasons why your images couldn’t calibrate: insufficient image overlap, the complex geometry of the area that you are trying to reconstruct or the Pix4D processing options that you were using. Looking at this study area, it seems that dense vegetation dominates. This article provides some methods to improve the calibration of the dataset: How to improve the outputs of dense vegetation areas?

    Cheers,
    Teodora
Article is closed for comments.