Image capture using webcam

I am using matlab for capturing image using a webcam(company-Labtec) whenever i get a snapshot the image appears Red.How should i overcome this problem?

Also how can I increase the shuter exposore time of the webcam?

OS-Windows XP

[manali jangam]

when the snapshot of images is recorded...its not showing its file format..how should we get that..????

[Mohan Kant]

the same problem with me please solve that problem

[Chaitanya Panse]

The problem with my GUI is that whenever i connect an external webcam and run in GUI the axis becomes very small that it is hardly seen. How do i overcome this problem? Please help.

Answer 1

[David Tarkowski]

I'm going to guess that the problem is the color space that your camera returns data in is not RGB. This is common for a lot of webcams. The commands commonly used to display images such as image or imshow expect RGB data. If you pass in YCbCr (or YUV) data, the result is an image that looks vaguely correct but has a pink and green hue to it.

There are a number of ways to work around this, but in your case, I suspect that the easiest will be to change the ReturnedColorSpace property of the videoinput object:

vid = videoinput('winvideo', 1);
set(vid, 'ReturnedColorSpace', 'RGB');
img = getsnapshot(vid);
imshow(img)

[Prateek]

Thanks Boss.your solution did work.

[prateek chaturvedi]

i even tried it out didnot work

[antriksh saxena]

thank you this solution work

[Image Analyst]

Alternatively, without using the Image Acquisition Toolbox, you might get by with the webcam tool : http://www.mathworks.com/support/2014a/matlab/8.3/demos/webcam-support.html

[mark]

thankyou :) it is working

[Mohan Kant]

Thank you its working

[kunal m]

its is not working error occur it show A timeout occurred during GETSNAPSHOT can u please help me in fixing that error

[Image Analyst]

Try this:

>> ver
>> which getsnapshot

What does it say? You probably don't have the Image Acquisition Toolbox installed.

[Ritika]

How to save the snapshots during recording...can u Please help me for this

Answer 2

[Mark Jones]

Alternatively, it may be that your camera needs to warm up. To allow for this, try using manual triggering and GETSNAPSHOT.

Answer 3

[Ian]

I got this to work, but is there a way to then read that image? Like to call it back so matlab can analyze it?

[Image Analyst]

What did you do? Did you call getsnapshot()? Did you call imwrite() or imread()? How can we discover what you did to say that it both worked but you don't have the image yet? Show your code.

[Ian]

camlist=webcamlist; cam = webcam(1); preview(cam); img=snapshot(cam); orignalimage=imread(img);

and then this error comes up:

Error using imread>parse_inputs (line 457) The filename or url argument must be a string.

Error in imread (line 316) [filename, fmt_s, extraArgs] = parse_inputs(varargin{:});

[Ian]

I get the image, but now I want to use that image to get other data, but I can't seem to read the image

[Anchit Dhar]

The SNAPSHOT command returns the RGB image. The "img" variable is your image. A call to IMREAD is not required.

[Ian]

Ahhh thank you very much! I have gotten the code to work now.

[Antonio Meza]

Thank you!! it works. Finally, i can finish my project. Greetengs from Mexico

Answer 4

[finalyear project]

Tried to take an image using webcam by following code

vid = videoinput('winvideo', 3);

set(vid, 'ReturnedColorSpace', 'RGB');

img = getsnapshot(vid);

imshow(img)

but still got black image.Can anybody please suggest something?

[Syed Aameer]

attach this code above to to your code axes(handles.axes1);

hImage=image(zeros(80,120,3),'Parent',handles.axes1); preview(vid,hImage);

Answer 5

[mohamed hushan]

vid = videoinput('winvideo', 1);
 set(vid, 'ReturnedColorSpace', 'RGB');
img = getsnapshot(vid); imshow(img)

after that how to save the snap images into folder?

Answer 6

[Shrey Garg]

webcam not working in matlab

it opensup logitech webcam nut it doesnot works and displays message that application already opened