Opencv affine transformation + projection transformation + homography matrix

Source: Internet
Author: User

I originally wanted to solve the displacement of small-scale moving objects with a single stress, but later I found that even a very small displacement would bring about a huge error or even a wrong solution. It seems that this method is not feasible, we still need to match and know the depth before we can start with the three-dimensional affine transformation ~
    • Estimaterigidtransform (): Calculate multiple two-dimensional point pairs or the optimal affine transformation matrix between images (two rows and column X3). h can be partial degrees of freedom, such as consistent shear.
    • Getaffinetransform (): Calculate the matrix H (two rows of column X3) between three two-dimensional points. The degree of freedom is 6.
    • Warpaffine (): Performs affine transformation on the input image
    • Findhomography: calculates the optimal single ing transformation matrix H (three rows of column X3) between multiple two-dimensional points, using the least mean square error or ransac method.
    • Getperspectivetransform (): calculates the transmission transformation matrix H between four two-dimensional points (three rows and column X3)
    • Warpperspective (): transmits and transforms the input image.
    • Perspectivetransform (): Perform transmission transformation on two-dimensional or three-dimensional vectors, that is, perform projection transformation on the input two-dimensional coordinate points or three-dimensional coordinate points.
    • Estimateaffine3d: Calculate the optimal three-dimensional affine transformation matrix H between multiple 3D points (3 rows and 4 columns)
    • Transform (): converts the n-dimensional vectors of the input, which can be used for Affine Transformation and Image Color transformation.
    • Findfundamentalmat: calculates the base matrix H between multiple points.
Quick Solution:
    • Question 1: How do I calculate the matrix of the three two-dimensional point-to-point affine transformations?
A: Use getaffinetransform ().
    • Question 2: How to calculate the affine transformation matrix between multiple two-dimensional points (using the minimum error criterion )?
A: Use estimaterigidtransform () or findhomography.
    • Question 3: how to calculate the transmission transformation between four two-dimensional points?
A: Use getperspectivetransform ().
    • Question 4: How do I calculate the affine transformation between multiple 3D points?
A: Use estimateaffine3d.
    • Question 5: How do I perform affine transformation on the input image?
A: Use warpaffine ().
    • Question 6: How do I perform transmission transformation on the input image?
A: Use perspectivetransform ().
    • Question 7: How do I perform an affine transformation on two-dimensional point pairs of input?
A: use transform ().
    • Question 8: how to perform projection transformation on the input 3D point pair?
A: Use perspectivetransform ().

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.