Forums - Is fcvGetPerspectiveTransformf32() approx result?

4 posts / 0 new
Last post
Is fcvGetPerspectiveTransformf32() approx result?
DaniilPattersson
Join Date: 17 Jul 12
Location: Russia
Posts: 23
Posted: Fri, 2012-07-27 00:16

Hi guys!

Is fcvGetPerspectiveTransformf32() use an approximation to get transform matrix?

 

  • Up0
  • Down0
jeff4s Moderator
Join Date: 14 Mar 12
Posts: 54
Posted: Fri, 2012-07-27 16:18

The matrix is obtained by solving a set of linear equations.

  • Up0
  • Down0
DaniilPattersson
Join Date: 17 Jul 12
Location: Russia
Posts: 23
Posted: Tue, 2012-07-31 03:49

I'm just have differrent from formula here results, so asked is it was a direct method or some approximation.

My src1:

268.72913; 274.75238; 297.70938; 285.03549; 294.884; 310.2301; 311.99765; 283.78845

src2:

310.26279; 263.5845; 314.30334; 275.39108; 314.85098; 240.5213; 296.16827; 253.77359

and output transform matrix:

5.4307547; -6.0508952; -0.41752285; 4.1475563; -4.6508889; 0.90742648; 0.015885137; -0.021309802; 1

  • Up0
  • Down0
jeff4s Moderator
Join Date: 14 Mar 12
Posts: 54
Posted: Sat, 2012-08-04 00:17

The solution for the system of linear equations uses the classical singular value decomposition. It should be more stable than the method in your link.

Have you tried other methods and compared with results from FastCV? In any case if you can confirm that FastCV gives unexpected results please report back.

Cheers,

-Jeff

  • Up0
  • Down0
or Register

Opinions expressed in the content posted here are the personal opinions of the original authors, and do not necessarily reflect those of Qualcomm Incorporated or its subsidiaries (“Qualcomm”). The content is provided for informational purposes only and is not meant to be an endorsement or representation by Qualcomm or any other party. This site may also provide links or references to non-Qualcomm sites and resources. Qualcomm makes no representations, warranties, or other commitments whatsoever about any non-Qualcomm sites or third-party resources that may be referenced, accessible from, or linked to this site.