Why do I get frames of incorrect size when using the GETFRAME function in MATLAB 7.0 (R14)?

When I use the IMREAD function to read an image file, then plot the image and use the GETFRAME function to get a movie frame from the resulting figure, the frame is sometimes a different size than the original image. For example, the following code may produce inconsistent results:

for i = 1:5

      imagedata = rand(200);

      figure;

      imshow (imagedata, []);

      frame = getframe(gca);

      [I,map] = frame2im(frame);

      fprintf('Size = %d,%d,%d\n',size(I));

      close;

end

Answer 1

[MathWorks Support Team]

This bug has been fixed in Release 14 Service Pack 3 (R14SP3). For previous product releases, read below for any possible workarounds:

There is a bug in the way that MATLAB 7.0 (R14) handles the GETFRAME function.

As a workaround, use the same figure for each frame as in the following example:

figure;

for i = 1:5

      imagedata = rand(200)

      imshow (imagedata, []);

      frame = getframe(gca);

      [I,map] = frame2im(frame);

      fprintf('Size = %d,%d,%d\n',size(I));

end

close;