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taking input from two cameras at a same time in Matlab

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how can i use and take input from two cameras at the same time?

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Accepted Answer

David Tarkowski
David Tarkowski on 11 May 2011
In general working with two cameras is the same as working with a single camera. You create a videoinput object for each device that you wish to capture from and the call start on each device:
vid1 = videoinput('winvideo', 1);
vid2 = videoinput('winvideo', 2);
start([vid1 vid2]);
These devices will be started at roughly the same time, but will not by synchronized due to delays imposed by the operating system and drivers in actually starting them. To synchronize multiple devices precisely, you generally need to use devices that support hardware triggering.

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Tiago
Tiago on 15 Feb 2013
my bad, but even something as simple as:
vid1 = videoinput('linuxvideo',1);
vid2 = videoinput('linuxvideo',2);
preview(vid1)
preview(vid2)
will give the same error.
Any advice on previewing two cameras?
Image Analyst
Image Analyst on 15 Feb 2013
You need to give it a handle to an image object:
axes(handles.axes1);
handleToImageInAxes1 = image(zeros(800,600));
% Turn on the live video.
preview(vidobj, handleToImageInAxes1);
axes(handles.axes2);
handleToImageInAxes2 = image(zeros(800,600));
% Turn on the live video.
preview(vidobj, handleToImageInAxes2);
Tiago
Tiago on 15 Feb 2013
I did like this:
vid1 = videoinput('linuxvideo',1);
vid2 = videoinput('linuxvideo',2);
handles.axes1 = subplot(1,2,1);
axes(handles.axes1);
handleToImageInAxes1 = image(zeros(800,600));
preview(vid1, handleToImageInAxes1);
handles.axes2 = subplot(1,2,2);
axes(handles.axes2);
handleToImageInAxes2 = image(zeros(800,600));
preview(vid2, handleToImageInAxes2);
and still the same error at the second preview. Any idea?

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More Answers (3)

Hassan Mehmood Khan
Hassan Mehmood Khan on 17 Sep 2017
i did this to get snapshot from two cams at same time:
% webcamlist identification
clc;
clearvars;
webcamlist
cam=webcam;
cam2=webcam(2);
cam.AvailableResolutions;
cam2.AvailableResolutions;
cam.Resolution='640x480';
cam2.Resolution='640x480';
% preview(cam);
% preview(cam2);
img=snapshot(cam);
img2=snapshot(cam2);
img3=snapshot(cam);
img4=snapshot(cam2);
figure;
subplot(3,3,1);
imshow(img3);
subplot(3,3,2);
imshow(img4);
output
ans =
'Webcam C170'
'Logitech HD Webcam C270'


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