I want to detect features of image 16 into rest 15 images..?

 clc ; % clearing the command window
n = 15;
intervel = 1;
photosave = 'y';
disp('Please wait...');
outputFolder = fullfile(cd);
if ~exist(outputFolder, 'dir')
mkdir(outputFolder);
end
a = imaqhwinfo;
[camera_name, camera_id, format] = getCameraInfo(a);
obj = videoinput(camera_name, camera_id, format);
set(obj, 'FramesPerTrigger', Inf);
set(obj, 'ReturnedColorspace', 'rgb')
vid.FrameGrabInterval = 5;
start(obj)
%obj = videoinput('winvideo',1);
preview(obj);
for i=1:n
img=getsnapshot(obj);
image(img);
if(photosave == 'y')
outputBaseFileName = sprintf('%d.jpg',i);
outputFullFileName = fullfile(outputFolder, outputBaseFileName);
imwrite(img,outputFullFileName,'jpg');
end
pause(intervel);

 d = dir('*.jpg');
n = length(d);
for imageNumber = 1:(n+0)
myFunction(imageNumber)
end
end

 closepreview;
stop(obj)
disp('The program successfully taken the photos');
disp('Done.');

 function [] = myFunction(imageNumber)
I2 = imread(sprintf('%d.jpg',imageNumber));
I2 = I2(:,:,3);
I1 = imread('16.jpg');
I1 = I1(:,:,3);

 points1 = detectHarrisFeatures(I1);
points2 = detectHarrisFeatures(I2);
[features1, valid_points1] = extractFeatures(I1, points1);
[features2, valid_points2] = extractFeatures(I2, points2);
[features1, valid_points1] = extractFeatures(I1, points1);
[features2, valid_points2] = extractFeatures(I2, points2);
indexPairs = matchFeatures(features1,features2)
matched_points1 = valid_points1(indexPairs(:,1),:);
matched_points2 = valid_points2(indexPairs(:,2),:);
figure; showMatchedFeatures(I1, I2, matched_points1, matched_points2);

I have written a code to detect features of image 16 into remaining 15 images.! But i am getting a following error.

 Undefined function or variable "indexPairs".

 Error in myFunction (line 13)
 matched_points1 = valid_points1(indexPairs(:,1),:);

 Error in TrialProg (line 32)
 myFunction(imageNumber)

I am using Matlab R2013a

How to solve an error..?

Answer 1

[Image Analyst]

Well, what values did you think indexPairs would have? You never assigned any values to it before you tried to use it, so it won't have any.

[Nimisha]

I have corrected the code.. Still it shows new error..

 Unable to allocate memory for an incoming image frame. Use IMAQMEM to modify
 the frame memory limit.

 Error in imaqdevice/getsnapshot (line 70)
    [snapshot, metadata] = getsnapshot(imaqgate('privateGetField', obj,
    'uddobject'));

 Error in TrialProg (line 20)
 img=getsnapshot(obj);

[Image Analyst]

That's not how I use getsnapshot(). I do things like this:

vidobj = videoinput('lumeneraimaqW32', 1, highestResFormat);
% Snap picture from camera.
snappedImage = getsnapshot(vidobj);  % This works.

You might want to call tech support.

[Nimisha]

 getCameraInfo
I have this ready function

[Image Analyst]

I never heard of it.

Answer 2

[Dima Lisin]

Hi Nimisha,

indexPairs should be the output of the matchFeatures function.

[Nimisha]

Right, I corected code. Still some error

[Dima Lisin]

Is it the error about the memory for the incoming frame? Are you running on 32-bit windows? How big is your video frame?

There are several things you can do:

• Use a 64-bit machine
• Make sure that the frame data type is set to uint8
• Set the camera to use lower resolution