Thread Subject:

imwrite by loop

Hi all,
I want take images from webcam and save them. problem if I want take more images

this is my code

vid = videoinput('winvideo', 1);
preview(vid);
for i=1:5
data= getsnapshot(vid);
pause(1);
imshow(data);
imwrite(data,'data1.jpg');
end

In this code I want save only five images How do this ?
How make loop for this ?

Thank you.

"Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8f5d5$5ra$1@fred.mathworks.com>...
> Hi all,
> I want take images from webcam and save them. problem if I want take more images
>
> this is my code
>
> vid = videoinput('winvideo', 1);
> preview(vid);
> for i=1:5
> data= getsnapshot(vid);
> pause(1);
> imshow(data);
> imwrite(data,'data1.jpg');
> end
>
> In this code I want save only five images How do this ?
> How make loop for this ?
>
> Thank you.

Read this thread.

Grzegorz

"Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8f5d5$5ra$1@fred.mathworks.com>...
> Hi all,
> I want take images from webcam and save them. problem if I want take more images
>
> this is my code
>
> vid = videoinput('winvideo', 1);
> preview(vid);
> for i=1:5
> data= getsnapshot(vid);
> pause(1);
> imshow(data);
> imwrite(data,'data1.jpg');
> end
>
> In this code I want save only five images How do this ?
> How make loop for this ?
>
> Thank you.

imwrite(data,['data',num2str(i),'.jpg']);

"Grzegorz Knor" <gknor@o2.pl> wrote in message <i8f62a$ie3$1@fred.mathworks.com>...
> Read this thread.
>
> Grzegorz

Sorry, I forgot a link:
http://matlabwiki.mathworks.com/MATLAB_FAQ#How_can_I_process_a_sequence_of_files.3F

Grzegorz

"Cris Luengo" <cris.luengo@google.for.my.name.to.contact.me> wrote in message <i8f65g$ohm$1@fred.mathworks.com>...
> "Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8f5d5$5ra$1@fred.mathworks.com>...

> imwrite(data,['data',num2str(i),'.jpg']);

WoW, Thank you so much for helping it is work perfectlly.
Now How can I put these images in certain folder and How make loop until webcam stop. I want take images if webcam run how do this?

Thank you again.

"Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8fals$n31$1@fred.mathworks.com>...
> "Cris Luengo" <cris.luengo@google.for.my.name.to.contact.me> wrote in message <i8f65g$ohm$1@fred.mathworks.com>...
> > "Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8f5d5$5ra$1@fred.mathworks.com>...
>
> > imwrite(data,['data',num2str(i),'.jpg']);
>
> WoW, Thank you so much for helping it is work perfectlly.
> Now How can I put these images in certain folder and How make loop until webcam stop. I want take images if webcam run how do this?
>
> Thank you again.

I don't know how you can tell from MATLAB that the webcam is turned off. I don't have that 'getsnapshot' function. If it were to return an empty array when it's off, for example, you could do:

ii = 1;
while 1
   data= getsnapshot(vid);
   if isempty(data)
      break;
   end
   ...
   imwrite(data,['data',num2str(ii),'.jpg']);
   ii = ii+1;
end

"Cris Luengo" <cris.luengo@google.for.my.name.to.contact.me> wrote in message <i8ferk$6ho$1@fred.mathworks.com>...
> "Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8fals$n31$1@fred.mathworks.com>...
> > "Cris Luengo" <cris.luengo@google.for.my.name.to.contact.me> wrote in message <i8f65g$ohm$1@fred.mathworks.com>...
> > > "Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8f5d5$5ra$1@fred.mathworks.com>...
> >
> > > imwrite(data,['data',num2str(i),'.jpg']);
> >
> > WoW, Thank you so much for helping it is work perfectlly.
> > Now How can I put these images in certain folder and How make loop until webcam stop. I want take images if webcam run how do this?
> >
> > Thank you again.
>
> I don't know how you can tell from MATLAB that the webcam is turned off. I don't have that 'getsnapshot' function. If it were to return an empty array when it's off, for example, you could do:
>
> ii = 1;
> while 1
> data= getsnapshot(vid);
> if isempty(data)
> break;
> end
> ...
> imwrite(data,['data',num2str(ii),'.jpg']);
> ii = ii+1;
> end

Thank you so much
Do you know how can I save these images in certain folder?

> > imwrite(data,['data',num2str(ii),'.jpg']);

> Thank you so much
> Do you know how can I save these images in certain folder?

Add the folder path to your file name e.g:
%
pathname = '/Volumes/ext1/my_folder/';
imwrite(data,[pathname, 'data',num2str(ii),'.jpg']);
%
That was a sample path for a Mac change it to whatever yours is.

"Sean " <sean.dewolski@nospamplease.umit.maine.edu> wrote in message <i8fvn0$npt$1@fred.mathworks.com>...
>
> > > imwrite(data,['data',num2str(ii),'.jpg']);
>
> > Thank you so much
> > Do you know how can I save these images in certain folder?
>
> Add the folder path to your file name e.g:
> %
> pathname = '/Volumes/ext1/my_folder/';
> imwrite(data,[pathname, 'data',num2str(ii),'.jpg']);
> %
> That was a sample path for a Mac change it to whatever yours is.

Thank you so much
It is work perfectlly.
This is my code now

vid = videoinput('winvideo', 1);
preview(vid);
for i=1:5
data= getsnapshot(vid);
imshow(data);
pathname = 'C:\Users\Bandar\Desktop\1111';
imwrite(data,[pathname, 'data',num2str(i),'.jpg']);
end

where 1111 name of folder but images not save in it, it is saving in Desktop Why?
And also name of each image chagned to 1111data1 like this, Why?

Thanks guys for your helping

I wouldn't do it that way. This is the way I'd do it (untested),
because this way lets you not have to worry about trailing slashes
(which was your problem).

% Define the folder outside of the loop.
pathName = 'C:\Users\Bandar\Desktop\1111';
% Create it if it doesn't exist.
if ~exist(pathName, 'dir')
  mkdir(pathName);
  % This will create to the full depth of the path.
  % Upper folder levels don't have to exist yet.
end

% Change your loop variable from i to frameNumber . i is not a good
choice.
for frameNumber = 1 : 5
  data = getsnapshot(vid);
  imshow(data);
  baseFileName = sprintf('data%d.jpg', frameNumber);
  fullFileName = fullfile(pathName, baseFileName);
  imwrite(data, fullFileName);
end % of the for loop

ImageAnalyst <imageanalyst@mailinator.com> wrote in message <e4bee7cc-fba2-4fe9-9e3e-629bf6d0b8bc@p26g2000yqb.googlegroups.com>...
> I wouldn't do it that way. This is the way I'd do it (untested),
> because this way lets you not have to worry about trailing slashes
> (which was your problem).
>
> % Define the folder outside of the loop.
> pathName = 'C:\Users\Bandar\Desktop\1111';
> % Create it if it doesn't exist.
> if ~exist(pathName, 'dir')
> mkdir(pathName);
> % This will create to the full depth of the path.
> % Upper folder levels don't have to exist yet.
> end
>
> % Change your loop variable from i to frameNumber . i is not a good
> choice.
> for frameNumber = 1 : 5
> data = getsnapshot(vid);
> imshow(data);
> baseFileName = sprintf('data%d.jpg', frameNumber);
> fullFileName = fullfile(pathName, baseFileName);
> imwrite(data, fullFileName);
> end % of the for loop

Thank you so much. really you are clever.

"Cris Luengo" <cris.luengo@google.for.my.name.to.contact.me> wrote in message <i8ferk$6ho$1@fred.mathworks.com>...
> "Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8fals$n31$1@fred.mathworks.com>...
> > "Cris Luengo" <cris.luengo@google.for.my.name.to.contact.me> wrote in message <i8f65g$ohm$1@fred.mathworks.com>...
> > > "Eng_Bandar " <nnnnhss@hotmail.com> wrote in message <i8f5d5$5ra$1@fred.mathworks.com>...
> >
> > > imwrite(data,['data',num2str(i),'.jpg']);
> >
> > WoW, Thank you so much for helping it is work perfectlly.
> > Now How can I put these images in certain folder and How make loop until webcam stop. I want take images if webcam run how do this?
> >
> > Thank you again.
>
> I don't know how you can tell from MATLAB that the webcam is turned off. I don't have that 'getsnapshot' function. If it were to return an empty array when it's off, for example, you could do:
>
> ii = 1;
> while 1
> data= getsnapshot(vid);
> if isempty(data)
> break;
> end
> ...
> imwrite(data,['data',num2str(ii),'.jpg']);
> ii = ii+1;
> end

Thank you man it is very good. It work perfectlly.

Now guys every thing is ok with folllowing code
_______________
vid = videoinput('winvideo', 1);
preview(vid);
% Define the folder outside of the loop.
pathName = 'C:\Users\Bandar\Desktop\1111';
% Create it if it doesn't exist.
if ~exist(pathName, 'dir')
  mkdir(pathName);
  % This will create to the full depth of the path.
  % Upper folder levels don't have to exist yet.
end

% Change your loop variable from i to frameNumber . i is not a good
%choice.
frameNumber=1;
while 1
    data= getsnapshot(vid);
    if isempty(data)
      break;
    else
        imshow(data);
        baseFileName = sprintf('data%d.jpg', frameNumber);
        fullFileName = fullfile(pathName, baseFileName);
        imwrite(data, fullFileName);
        frameNumber=frameNumber+1;
    end
end
_______________

I run it and every thing OK but if I use stop(vid) still work ( not camera but capture not stop ) I want it stop if I stop camera How do this ?
this is last step

Thank you for all

I so sorry for this big mistake I put
data= getsnapshot(vid);
in first line in endless loop of course it is not stop ( hahaha )
sorry I will try to solve it and also I need your help you are very nice

Thank you again

Well, how do you want to exit/stop the loop? When the user hits a key? When you get to a certain number of iterations? When you check a checkbox, or push a button? Some other way?

"Image Analyst" <imageanalyst@mailinator.com> wrote in message <i8ltag$t5e$1@fred.mathworks.com>...
> Well, how do you want to exit/stop the loop? When the user hits a key? When you get to a certain number of iterations? When you check a checkbox, or push a button? Some other way?

Thank you
I want it by push button (In GUI)

On Oct 8, 4:42 am, "Eng_Bandar " <nnnn...@hotmail.com> wrote:
> "Image Analyst" <imageanal...@mailinator.com> wrote in message <i8ltag$t5...@fred.mathworks.com>...
> > Well, how do you want to exit/stop the loop?  When the user hits a key?  When you get to a certain number of iterations?  When you check a checkbox, or push a button?  Some other way?
>
> Thank you
> I want it by push button (In GUI)

------------------------------------------------
One way to do it is to set a global variable when you push the button,
and have the loop check for it.
Button callback says
global continueSnapping ;
continueSnapping = false;

and your loop says
global continueSnapping ;
continueSnapping = true;
while continueSnapping
% snap images
end