Camera rig alignment

[Adrian Onsen]

I have set up a camera rig that has 5 cameras.
2 cameras pointing left, 2 cameras pointing right and one camera pointing up.

The position and rotation of all cameras relative to one another is know.

I will be moving this camera rig to take sets of images for a photogrammetric reconstruction.

Is there a way fix a set of cameras in Meshroom, and have the software align the camera rig locations rather then the individual cameras?

[Adrian Onsen]

Camera rig setup diagram

[Fabien Castan]

Hi,

Does this answer your question?

https://meshroom-manual.readthedocs.io/en/latest/faq/multi-camera-rig/multi-camera-rig.html

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De : alice...@googlegroups.com <alice...@googlegroups.com> de la part de Adrian Onsen <aon...@gmail.com>
Envoyé : mercredi 7 octobre 2020 17:29
À : AliceVision <alice...@googlegroups.com>
Objet : Re: Camera rig alignment

 

⚠️ Do not click or open unknown attachments ⚠️ **

Camera rig setup diagram.

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[Adrian Onsen]

Thank you.

I will test out this workflow.

So there is no way to tell meshroom the actual relative positions of all the cameras in the rig?

[Fabien Castan]

Hi,

It is not possible from the UI. But you could manually create a .sfm file (json format).

The easiest way would be to make a reconstruction in a well textured environment (like a calibration step) to retrieve the relative positions.

And use that to initialize your other reconstructions.

Let us know how it goes!

Best,

Fabien

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De : alice...@googlegroups.com <alice...@googlegroups.com> de la part de Adrian Onsen <aon...@gmail.com>

Envoyé : vendredi 9 octobre 2020 16:40

To view this discussion on the web visit https://groups.google.com/d/msgid/alicevision/fefcbed7-d31c-4415-821d-bd7a4019a1d9n%40googlegroups.com.

[Adrian Onsen]

I mounted 2 cameras on a stick, and shot 12 images with each camera, as a test.

I followed the instructions here for the folder and file naming:
https://meshroom-manual.readthedocs.io/en/latest/faq/multi-camera-rig/multi-camera-rig.html 

After adding the folders to Meshroom, the Rig and Rig Sub-Pose values (of the Viewpoints parameter in CamareaInit node) are still -1.
Should those values have changed to something else? Do I have to change them manually?

How do I know if Meshroom is treating the cameras as a RIG rather then individual cameras?

[Fabien Castan]

>  After adding the folders to Meshroom, the Rig and Rig Sub-Pose values (of the Viewpoints parameter in CamareaInit node) are still -1. 

They should be initialized. Try setting verbose=trace on CameraInit and share the log.

Your rig indexes should start at 0.

[Adrian Onsen]

I am using a couple of action cameras for this test. To bring the images into Meshroom, I multiselect the two folders (0, and 1) and drag and drop them into the "Images" pane.

Is that the correct image loading procedure?

The log Output:

Program called with the following parameters:

 * allowSingleView = 1

 * defaultCameraModel = "" (default)

 * defaultFieldOfView = 45

 * defaultFocalLengthPix = -1 (default)

 * defaultIntrinsic = "" (default)

 * groupCameraFallback =  Unknown Type "enum EGroupCameraFallback"

 * imageFolder = "" (default)

 * input = "C:/Users/outsider/AppData/Local/Temp/MeshroomCache/CameraInit/39f3da04a405c4653d71f7eb2efd271f1d14d4e4//viewpoints.sfm"

 * output = "C:/Users/outsider/AppData/Local/Temp/MeshroomCache/CameraInit/39f3da04a405c4653d71f7eb2efd271f1d14d4e4/cameraInit.sfm"

 * sensorDatabase = "C:\Users\outsider\Desktop\Meshroom-2019.2.0\aliceVision\share\aliceVision\cameraSensors.db"

 * verboseLevel = "info"

[12:38:57.995709][info] CameraInit report:

- # views listed: 22

   - # views with an initialized intrinsic listed: 22

   - # views without metadata (with a default intrinsic): 0

- # intrinsics listed: 2