MATLAB: Using pause() and readframe() – the pause is not affecting the output

readframe

I am trying to pause the video and graphs when the graphs reach a maximum. The code successfully pauses in the matlab figure window but, when I go back and watch the video 'compositevid2' in the default windows player, the video does not slow down at all. I've tried increasing the the pause time to two minutes and haven't noticed any change to the outputed video. Is it possible to do what I am wanting to do?
%open the video
 inputVid = VideoReader('760-255-20 Test B04 - 3000 fps.wmv');
 %calculate total number of frames, mostly to show you what data is
 %available in the object.  
 TotnumFrames = round(inputVid.FrameRate*inputVid.Duration);
%%now add stats to it.
%initiate new composite video file 
mergedobj = VideoWriter('compositevid2','Motion JPEG AVI');
mergedobj.FrameRate = inputVid.FrameRate;  %match same framerate 
mergedobj.Quality=100;
open(mergedobj); 
%start the stitch
hfig = figure;
k = 1; %use for my data
[t, p4, p11, dps] = grabfromexcel(); %pull the data from excel
[maxp4Value, indexAtMaxp4]=max(p4);
tValueAtMaxp4Value = t(indexAtMaxp4(1));
[maxp11Value, indexAtMaxp11]=max(p11);
tValueAtMaxp11Value = t(indexAtMaxp11(1));
%while loop until there are no more frames
n=30;
m=30;
while k <= (length(t)/dps)
    %read in frame
    singleFrame = readFrame(inputVid);   
    % display frame
    gaugeposition=[700, 600, 700, 700; 1400, 600, 1400, 700];
    textposition=[700,700; 1400, 700];
    labelgauges=cell(2,1);
    gaugenumbers = [4, 11];
    for ii=1:2
    labelgauges{ii}=['Gauge ' num2str(gaugenumbers(ii), '%.0f')];
    end
    RGB1=insertShape(singleFrame,'line',gaugeposition, 'Color', 'red', 'LineWidth',3);
    RGB2=insertText(RGB1, textposition, labelgauges,'FontSize', 40, ...
        'BoxColor', 'white', 'BoxOpacity', .3, 'TextColor', 'red', 'AnchorPoint', 'CenterTop');
    subplot(4,4,1:12),imagesc(RGB2), axis off, axis equal;
        if any(t(1,((k-1)*dps)+(1:dps)) == tValueAtMaxp4Value)
            text(tValueAtMaxp4Value, max(p4), commentp4, 'HorizontalAlignment', 'right')
            pause on
            pause (40)
            pause off
        end
        if any(t(1,((k-1)*dps)+(1:dps)) == tValueAtMaxp11Value)
            text(tValueAtMaxp11Value, max(p11), commentp11, 'HorizontalAlignment', 'left')
            pause on
            pause (40)
            pause off
        end
    %plot the data
    subplot(4,4,13:14),plot(t(1,((k-1)*dps)+(1:dps)),p4(1,((k-1)*dps)+(1:dps)),'k-.'),hold on;
    axis on
    title('Pressure Gauge 4 vs Time');
    ylim([-1 (max(p4)+.25)])
    xlim([0 max(t)])
    commentp4= ['Max Pressure= ', num2str(maxp4Value), ' \rightarrow '];
        if any(t(1,((k-1)*dps)+(1:dps)) == tValueAtMaxp4Value)
            text(tValueAtMaxp4Value, max(p4), commentp4, 'HorizontalAlignment', 'right')
            pause on
            pause (40)
            pause off
        end
    subplot(4,4,15:16),plot(t(1,((k-1)*dps)+(1:dps)),p11(1,((k-1)*dps)+(1:dps)),'k-.'),hold on;
    axis on
    title('Pressure Gauge 11 vs Time');
    ylim([-1 (max(p4)+.25)])
    xlim([0 max(t)])
    commentp11= [' \leftarrow Max Pressure= ', num2str(maxp11Value)];
        if any(t(1,((k-1)*dps)+(1:dps)) == tValueAtMaxp11Value)
            text(tValueAtMaxp11Value, max(p11), commentp11, 'HorizontalAlignment', 'left')
            pause on
            pause (40)
            pause off
        end
      set(gcf, 'WindowState', 'maximized');
      %grab what the figure looks like
      frame = getframe(hfig);
      %write to file.
      writeVideo(mergedobj, frame);
      %increment k for my data.  
      k = k+1;
end
  %close the object
  close(mergedobj)

Best Answer

getframe and writeVideo merely store images as frames of a movie which does not affect playback speed.
Follow Walter Roberson's advice in this answer:
https://www.mathworks.com/matlabcentral/answers/437855-how-can-i-change-the-speed-of-the-video#answer_354594
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