create a gif or video using this sequence of figures

Question

Alberto Acri 2020-12-26

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/702962-create-a-gif-or-video-using-this-sequence-of-figures

评论： Walter Roberson 2020-12-29

I want to create a gif or video using this sequence of figures:

plot of figure 1
pause(0.8);
hold on;
plot of figure 2;
pause(0.8);
plot of figure 3;
pause(0.8);
plot of figure 4;
pause(0.8);
hold off

Is it possible ?

7 个评论
显示 5更早的评论隐藏 5更早的评论

Walter Roberson 2020-12-27

在 MATLAB Online 中打开

n = 1:0.5:5

That is a vector of values

if n == 1

You are testing a vector of values. For the if to succeed, all of the tests need to be true simultaneously . The first element where n is 1 succeeds, but where n = 1.5, 2, 2.5, and so on all fail, so n == 1 is [true] followed by a bunch [false], and if needs them all to be true to work. So the if will not match. Only the else will happen.

The else branch will write one frame.

You do not have any looping.

Also, the colormap needs to be the same for all of the frames. That is not a requirement of GIF file format, but imwrite() is not able to write different colormaps for each frame, so imwrite() would silently rewrite your coloring. I at least made it obvious here. Now you just have the problem that the colormap derived from the first image might not be representative of the rest. You would probably be better off using a fixed colormap.

% Capture the plot as an image 
  h=figure
  filename = 'testAnimated.gif';
  for n = 1:0.5:5
      frame = getframe(h); 
      im = frame2im(frame); 
      % Write to the GIF File 
      if n == 1
          [imind,cm] = rgb2ind(im,256); 
          imwrite(imind, cm, filename, 'gif', 'Loopcount', inf); 
      else
          imind = rgb2ind(im, cm);
          imwrite(imind, cm, filename, 'gif', 'WriteMode', 'append'); 
      end 

Alberto Acri 2020-12-27

but I want to create a video with the sequence of images above.

Walter Roberson 2020-12-27

Your question asked to create a gif or a video, and the above shows creating a gif.

You can use VideoWriter; see for example https://www.mathworks.com/help/matlab/ref/videowriter.writevideo.html#bus2hel-1_sep_bus0tu7

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Gaurav Garg 2020-12-29

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/702962-create-a-gif-or-video-using-this-sequence-of-figures#answer_586212

Hi,

Apart from all the resources provided in the comments above, the below links would surely help you -

1.) Link 1

2.) Link 2

The above 2 links contain similar questions answered by MATLAB users and accepted too.

2 个评论
显示无隐藏无

Alberto Acri 2020-12-29

在 MATLAB Online 中打开

I used link 1 shown below:

N=1   % set
for i = 1:N
    figure(1)  
%    imshow(processo(:,:,1,i))
plot of figure 1
pause(0.8);
hold on;
plot of figure 2;
pause(0.8);
plot of figure 3;
pause(0.8);
plot of figure 4;
pause(0.8);
hold off
      F(i) = getframe(gcf) ;
      drawnow
    end
  % create the video writer with 1 fps
  writerObj = VideoWriter('myVideo.avi');
  writerObj.FrameRate = 10;
  % set the seconds per image
% open the video writer
open(writerObj);
% write the frames to the video
for i=1:length(F)
    % convert the image to a frame
    frame = F(i) ;    
    writeVideo(writerObj, frame);
end
% close the writer object
close(writerObj);