save graph in video

Hi all,

My supervisor gave me this code. I modified it to make it work like i wnated. However i would like at the end of the code to save the video that has been created. Does someone know how to do that?

Thank you for your help

jonathan

clear all
close all
clc

cd('D:\Raw_data\Surface\Autumn\Lat_lon\');
addpath C:\Matlab_download\m_map1.4f\

load ('October_01_2014_surface_lat_##.mat');
load ('October_01_2014_surface_lon_##.mat');

lat1 = lat(4187,:);
lon1 = lon(4187,:);

X=lon1; 
Y=lat1; 
%day = M(a,2);
%month = M(a,3);
%year = M(a,4);
%hour = M(a,5);
%mins = M(a,6);

LNMIN = -5.8;%horizontal
LNMAX = -2.5;
LTMIN = 52.7; %vertical
LTMAX = 55;

m_proj('utm','lon',[LNMIN,LNMAX],'lat',[LTMIN,LTMAX],'zone',30,'hem',0,'ell','wgs84');

%%
clf;
m_gshhs_f('patch',[.7 .7 .7],'edgecolor',[.2 .2 .2]),hold all
m_grid('linestyle','none','box','fancy','tickdir','in','fontsize',11,'Fontname','Times New Roman');
set(gca,'tickdir','out','fontweight','bold','fontsize',15,'Fontname','Times New Roman');

% time step 1:
h1 = m_plot(X(1),Y(1),'.-b');
hold on
h2 = m_plot(X(1),Y(1),'or');
h3 = m_plot(X(1),Y(1),'^','color',[0 0.6 0],'linewidth',2);
%title(datestr(datenum(year(1),month(1),day(1),hour(1),mins(1),0)));

for it=2:length(lat1)
    
    lag = min([it,25]);
    
    delete(h1);
    delete(h2);
    
    h1 = m_plot(X(it-lag+1:it),Y(it-lag+1:it),'.-b');
    h2 = m_plot(X(it),Y(it),'or');
    
    % work out date and display it....
    %title(datestr(datenum(year(it),month(it),day(it),hour(it),mins(it),0)));
    
    drawnow
    pause(0.05)
end

Answer 1

[Image Analyst]

You can use exportgraphics() to save figures or axes. If you want an example of how to draw something in an axes and change it and make a movie out of it, check out my simple attached example.

[Jonathan Demmer]

Wow!! That is amazing!! Thank you so much!!!

Answer 2

[Adam Danz]

1. Use F=getframe() to store an image of the plot for each iteration of the for-loop. Save F to file if you want to replay the movie without re-collecting the frames.
2. Use movie(F,__) to play back the movie.

See Method 3: Create a movie for a demo.

[Jonathan Demmer]

Thank you fro your answer.

Save F i add it inside the loop, right?

[Jonathan Demmer]

Hi,

I added in the loop

    F = getframe;
    
    Save F;

and this error appeared:

Undefined function 'Save' for input arguments of type 'char'.

Error in Video_aquaculture (line 79)

Save F;

Would you mind to explain me what happened please?

[Adam Danz]

> Save F i add it inside the loop, right?

No. Check out the example in the link I shared. You only need to save F to file if you want to play it later.

> Undefined function 'Save' for input arguments of type 'char'.

save is not capitalized.

[Jonathan Demmer]

Ok it works!! tahnk yo uvery much!! However it saves F into a matrix, would it be possible to save it as a video (.avi)?

[Adam Danz]

You can use VideoWriter which is what ImageAnalyst is doing, I believe.

There's also a nice demo in the documentation,

https://www.mathworks.com/help/matlab/ref/videowriter.html#busy5fx-1_sep_bus0tu7