Error using VideoWriter/writeVideo (line 344) Frame must be 434 by 343

I getting error: Error using VideoWriter/writeVideo (line 344) Frame must be 434 by 343

Error in movie_trial5 (line 22) writeVideo(v,getframe(gca))

Here is my code:

nframes=50;
Frames=moviein(nframes);
x1=linspace(0,L,1000);
x2=linspace(L,2*L,1000);
figure
v = VideoWriter('E:\newfile.avi');
open(v)
for t=1:nframes
  y1=sin(x1)*cos(20*t);
  y2=sin(2*L-x2)*cos(20*t);
  plot (x1,y1,x2,y2,'Linewidth',3)
  writeVideo(v,getframe(gca))
end
close(gca)
close(v)

[Geoff Hayes]

Perhaps the frame size is changing on an iteration of your for loop which leads to the error. Try doing

 for t=1:nframes
   y1=sin(x1)*cos(20*t);
   y2=sin(2*L-x2)*cos(20*t);
   myFrame = getframe(gca);
   size(myFrame.cdata)
   writeVideo(v,myFrame)
 end

Does the size of the frame ever change?

Answer 1

[Walter Roberson]

nframes=50;
Frames=moviein(nframes);
x1=linspace(0,L,1000);
x2=linspace(L,2*L,1000);
figure
v = VideoWriter('E:\newfile.avi');
open(v)

ax = gca();

for t=1:nframes
  y1=sin(x1)*cos(20*t);
  y2=sin(2*L-x2)*cos(20*t);

    if t == 1
      h = plot(ax, x1, y1, x2, y2, 'Linewidth',3);
      set(ax, 'XLimMode', 'manual', 'YLimMode', 'manual');
    else
      set(h(1), 'YData', y1);
      set(h(2), 'YData', y2);
    end
    drawnow();

    writeVideo(v,getframe(ax))
  end
  close(gca)
  close(v)

Besides being more efficient, this avoids the chance that the frame will change size.

Answer 2

[venus]

A simple solution is to keep the first figure with its size (with using hold on) and plot all the data in it.

nframes=50;
Frames=moviein(nframes);
x1=linspace(0,L,1000);
x2=linspace(L,2*L,1000);
myfig = figure();
hold on
v = VideoWriter('E:\newfile.avi');
open(v)
for t=1:nframes
  y1=sin(x1)*cos(20*t);
  y2=sin(2*L-x2)*cos(20*t);
  plot (x1,y1,x2,y2,'Linewidth',3)
  writeVideo(v,getframe(gca))
  clf(myfig);
end
close(gca)
close(v)