How to add image 'x' to even frames and one image 'y' to odd frames

Hello,

I have a video that we will call 'x' and some images that we will call 'output_cross_alfa' and 'output_cross_Nalfa'.

My goal is to make the sum of 'x' with 'output_cross_alfa' in the even frames, and in the odd frames the sum of 'x' is done with 'output_cross_Nalfa'. The final video should be:

frame1 = frame1 + output_cross_Nalfa;

frame2 = frame2 + output_cross_alfa;

frame3 = frame3 + output_cross_Nalfa;

frame4 = frame4 + output_cross_alfa;

......

To do this I used this code:

for ii = 1: 2: length (imageNames)
    for kk = 2: 2: length (imageNames)
        img1 = im2single (imread (fullfile (workingDir, 'images', imageNames {ii})));
        image_2 = im2single (img1 + output_cross_alfa);
        img2 = im2single (imread (fullfile (workingDir, 'images', imageNames {kk})));
        image_1 = im2single (img2 + output_cross_Nalfa);
        output = uint8 (image_par + image_par);
        writeVideo (outputVideo, output);
    end
end

But I only get screenshots in black and gray when representing it.

To represent it I use this:

shuttleAvi = VideoReader (fullfile (workingDir, 'shuttle_out.avi'));
ii = 1;
while hasFrame (shuttleAvi)
    mov (ii) = (im2frame (readFrame (shuttleAvi)));
    ii = ii + 1;
end
figure, imshow (mov (1) .cdata, 'Border', 'tight');
movie (mov, 1, shuttleAvi.FrameRate); 

And I have no idea what the failure may be.

Answer 1

[Prabhan Purwar]

Hi,

According to your description there doesn't seem any need for nested loops. Try making use of the following code:

outputVideo= VideoWriter('newfile.avi');
open(outputVideo);
for ii = 1: 2: length (imageNames)
   kk=ii+1;
        img1 = im2single (imread (fullfile (workingDir, 'images', imageNames {ii})));
        image_2 = im2single (img1 + output_cross_alfa);
        img2 = im2single (imread (fullfile (workingDir, 'images', imageNames {kk})));
        image_1 = im2single (img2 + output_cross_Nalfa);
        output = image_1;
        writeVideo (outputVideo, output);
        output = image_2;
        writeVideo (outputVideo, output);
end
close(outputVideo);

Hope it helps.

[Alber]

Thank you so much. Finally I solved my problem using one conditional like : if (rem(i,2)== 0)