How to connect SJCAM SJ4000 as a webcam to MATLAB

Hi, I have just bought a SJCAM action camera, model SJ4000.

It is able to function as a normal webcam on the PC. Hence, I tried connecting it to MATLAB as a webcam so that I can acquire images through MATLAB for an image processing project, however, the following error showed up:

P.S.: I have installed the MATLAB Support Package for USB Webcams and have updated the SJ4000 camera to its latest firmware.

>> webcamlist

ans =

    cell

      'J1455 '

>> cam = webcam('J1455 ')
Warning: The following error was caught while executing
'matlab.webcam.internal.WebcamController' class destructor:
Struct contents reference from a non-struct array object.

Error in matlab.webcam.internal.WebcamController/delete

Error in matlab.webcam.internal.WebcamController

Error in webcam (line 159)
                    matlab.webcam.internal.WebcamController(devName, devID); 
> In matlab.webcam.internal.WebcamController
  In webcam (line 159) 
Error. The format exposed by the webcam is not supported.

I have tried connecting other webcams (BisonCam, NB Pro and Logitech C170 webcam) to MATLAB and has managed to get them working, but not for this SJ4000 camera.

I would like to know what's the solution to this error, your help is much much appreciated!

[Grzegorz Wieczorek]

I managed it that way:

>> webcamlist

ans =

    2×1 cell array

      'Chicony USB 2.0 Camera'
      'J1455 '

>> obj = videoinput('winvideo', 2);
>> obj.SelectedSourceName = 'input1';
>> obj = videoinput('winvideo', 2, 'MJPG_1920x1080');
>> preview(obj)

And it worked for me.

[Pragnesh Gamit]

how to take snapshot of the preview ?

Answer 1

[Eugene Lipunov]

imaqhwinfo

% choose the source by index vidid, get vid

vid = videoinput ('winvideo', vidid);

% optional: src = getselectedsource (vid);

preview (vid);

% loop to get snapshots (do not close preview)

img = getsnapshot (vid);