appdesigner: use a slider to play a video

Good morning, I am making a program in appdesigner that needs to play a video and through a slider you can configure the second of video in which it is located. That is to say if the video lasts 30 seconds, the slider will have a length of 30 and if I put the arrow of the slider in 10 seconds the video will show what appears in the second 10. I have achieved that in an axes I see the video but it plays from beginning to end without stopping. I would appreciate if someone could help me.

this is the capture of the code that I have generated in the callback of a button in which you can choose the video that will be played in the axes when you press it.

Answer 1

[Antoni Garcia-Herreros]

Hello Marina,

You could start by creating a startup Function where you create an array with all frames. Something like this:

function seleccionVideoButtonPushed(app, event)

%Select the video same way you are doing right now


        video=VideoReader(foldervideo);
        numFrames=video.NumberofFrames;
        app.AllFrames=zeros(video.Height,video.Width,3,numFrames); 
        % This array will contain all the video frames 
        for a=1:numFrames
            frame=read(video,a);
            app.AllFrames(:,:,:,a)=frame;
        end
    end

Then you'll have to add a callback function when the slider is moved:

        function SliderValueChanging(app, event)
            changingValue = event.Value;
            idx=floor(changingValue); % You may want to adjust this value based on the temporal resolution of your video
            % The other option is to change the length of the slider to be
            % the same as the number of frames.
            imshow(app.AllFrames(:,:,:,idx),'Parent',app.UIAxes)
        end

Hope this helps!