saving captured images to a folder (error in imwrite function)

Dear friends,

When I run the following code to save the captured image files to a folder it works. But If I set the n value (FramesPerTrigger) to more than 1 then I get an error message.

vid = videoinput('winvideo', 1, 'RGB24_1920x1080');
src = getselectedsource(vid);
vid.LoggingMode = 'memory';
m=5;
vid.TriggerRepeat = 5;
triggerconfig(vid, 'manual');
vid.TimerFcn = 'trigger(vid)';
vid.TimerPeriod = 1; 
n=1;
vid.FramesPerTrigger = n; 
start(vid)
mkdir('C:\Documents and Settings\suleyman\My Documents\MATLAB\trial\deneme') 
for i=1:m*n
imagename = ['C:\Documents and Settings\bae50742\My Documents\MATLAB\kinking\deneme\deneme5_Sample1_image' num2str(i) '.jpg'];
imwrite(getdata(vid), imagename);
end
stop(vid)

Here is the error message;

Error using writejpg (line 38)
4-D data not supported for JPEG files

Error in imwrite (line 477)
        feval(fmt_s.write, data, map, filename, paramPairs{:});

How can I fix this problem? thank you in advance for your help.

Answer 1

[Youssef Khmou]

hi,

The data you are trying to save are 4D , its a sequence of images as :

Width x height x channels x Frames

I suggest this way : After the acquisition process :

 data=getdata(vid);

 % Try to look at the size of the data : >>size(data)

 N=size(data,4); % N is the number of frames 

 for x=1:N
 filename=strcat('Image',int2str(x),'.jpg'); %  OR JPEG AS  YOU LIKE
 imwrite(data(:,:,:,x),filename);
 end

[Suleyman Deveci]

Hi Youssef, thank you for your reply.

It didn't work because N is always equal to "FramesPerTrigger" value but I normally have "TriggerRepeat x FramesPerTrigger" times number of image file to save.

Regards.

Suleyman

Answer 2

[kash]

Try this code

close all
imaqhwinfo
dev_info=imaqhwinfo('winvideo',1)
%info=imaqhwinfo('winvideo')

   celldisp(dev_info.SupportedFormats)
  vid=videoinput('winvideo',1,'RGB24_1920x1080');

%Open Figure
hFigure=figure(1);
%set parameters for video
%Acquire only one frame each time
triggerconfig(vid,'Manual');
set(vid,'framespertrigger',1);
%Go on forever untill stopped
set(vid,'triggerrepeat',Inf);
%Get a grayscale image
set(vid,'ReturnedColorSpace','RGB');
start(vid);
preview(vid);
data = getsnapshot(vid);

[Save,savename] = uiputfile('*.jpg','save this file')
fname=fullfile(savename,Save);
imwrite(data,fname);  % where F is your image
 stop(vid),delete(vid),clear('vid')