Topics

1

General / [SOLVED] Project points of doll model into original frame

« on: April 10, 2015, 11:20:41 AM »

I downloaded the data of the doll tutorial, with .obj file and input images included.
I've exported from the photoscan project file the cameras photoscan file .xml.  Using the parameters included in it, I've tried to reproject the points of the mesh into the first image, thus I've copied the intrinsic and extrinsic parameters for that camera and apply the projection function provided in the manual (and the one provided in Caltech vision calibration toolbox) but the the points projection is completely wrong!
 
I think that either there is a bug in Photoscan or the cameras and obj files refers to different world coordinates.
Could someone help me please.

2

General / Field explanation of photoscan .xml camera file

« on: April 07, 2015, 12:53:46 PM »

What do the fields embedded in the tag <regoin> </region> refer to?
Are the coordinates of the 3d .obj defined in the region space? Should I therefore translate the 3d coordinates according to it?

Who can help me?
Thank you in advance.

3

Bug Reports / [SOLVED] Errors exporting the data

« on: April 03, 2015, 03:40:18 PM »

I am using Photoscan 1.1.4 64bit for windows.
I need to import the 3d model computed by photoscan into matlab. The model has been computed using pre-calibrated fix parameters.
I exported the model as an .obj file and the extrinsic parameters either in the format phi kappa omega .txt OR photoscan .xml. The extrinsic parameters in this two models differ by a rotation matrix, for instance, the rotation matrix exported in the .xml file is the R matrix of the .txt file rotated by 180° around the x axis.

Moreover, I get a "correct" reprojection of the points only when I use the phi kappa omega .txt file to obtain the parameters, and I multiply the x coordinate of the translation vector by -1 and invert the x-axis on the frame i.e. u = width - u. Or, in other words, when  I multiply the x coordinate of the translation vector and the x focal length by -1.

To reproject the 3D-points I followed the schema reported in the manual and I even tried to apply the function developed into the calibration toolbox from Caltech. The reprojection using these two methods are identical, but they are correct only when I apply that sort of patch.

EDIT: I checked with another model exported from the same set of photos and configuration, this time neither that patch works... This model is smaller and it is not centered in the z axis as the previous one.


Thank you in advance.