video overlay to an still image

Dear Community,

I am looking for info how to coregister a live video feed to a still image.

Problem: assume the same posture seen by a camera to a reference image.

Example: I have a .jpg of an ideal posture, e.g. person standing with a tennis racket and ready to serve. Call this reference image.

I would like this image as a background image on a live video camera.

A different person in front of the video camera has to mimic as close as possibly the position of the reference image.

Ideally the application should give immidiate numerical feedback in form of an percentage or a transformation matrix dispaying the differences.

Any help with fusing these two different modalities would be appreciated.

Perhaps there are other open source applications, which come with

this functionality already integrated. If so please provide information.

Thank you,

fm

Answer 1

[Rahul]

Hi @frank millo,

In order to overlay your image on a live video feed, as video can be considered as a collection of images which are essentially matrices in MATLAB, hence adding the image to be overlayed as pixels to the collections along with appropriate alpha adjustment. A working example can be found in the below MATLAB Answer where an image was overlayed over another image:

https://www.mathworks.com/matlabcentral/answers/414351-overlay-image-on-top-of-image

Also, functions like 'preview' can be used to achieve the same with live cam feed. The below MATLAB Answer explains how the same can be done:

https://www.mathworks.com/matlabcentral/answers/88617-overlay-an-image-in-preview-video

Please refer to the following MathWorks documentations for more information:

'preview': https://www.mathworks.com/help/releases/R2024a/matlab/supportpkg/webcam.preview.html

'imoverlay': https://www.mathworks.com/help/releases/R2024a/images/ref/imoverlay.html

Thanks.