How to write a video from png files and/or matlab figures
8 visualizzazioni (ultimi 30 giorni)
Mostra commenti meno recenti
Anna Clouvel-Gervaiseau
il 23 Set 2020
Commentato: Bjorn Gustavsson
il 23 Set 2020
Hello,
I've been trying to write a simple code that takes a sequence of images and makes a video from them. However, the video file always ends up empty or unreadable, and I have no idea why the code isn't working. This is the code :
video23 = VideoWriter('video23.avi');
%video23.FrameRate = 1;
open(video23);
baseN = 'VectorOverlay';
d = '_';
e = 'Individual.png';
f = '-';
for i = 1:87
file_name = [baseN,d,num2str(i),f,num2str(i+1),d,e];
%VectorOverlay_1-2_Individual.png from PIV analysis
im = imread(file_name);
figure(1)
image(im)
writeVideo(video23, im);
end
close(video23)
implay(video23);
Can someone help me? I also have the images saved as Matlab figures, but matlab won't recognize the file format when I try and get it to read the files.
2 Commenti
Risposta accettata
Bjorn Gustavsson
il 23 Set 2020
Try modifying your call to writeVideo to this:
currFrame = getframe(gcf);
writeVideo(vidObj,currFrame);
HTH
2 Commenti
Bjorn Gustavsson
il 23 Set 2020
That is strange. (unless you happened to resize your figure-window, since in this version the getframe call captures the entire figure and then you try to write that frame to the avi-file. That must not change size from frame to frame...)
You can try to simply check the sizes of all frames:
for i1 = 1:87
file_name = [baseN,d,num2str(i1),f,num2str(i1+1),d,e];
%VectorOverlay_1-2_Individual.png from PIV analysis
im = imread(file_name);
figure(1)
image(im)
currFrame = getframe(gcf);
% writeVideo(vidObj,currFrame);
szCF = size(currFrame);
frame_sz(i1,1:numel(szCF)) = szCF;
end
Then you can check that the frame-size doesn't change through the loop.
HTH
Più risposte (0)
Vedere anche
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!