how to convert video to image

i want to know the command that can help me to convert video frame into image to image processing this image and detect the required extracted features and locate the object

[Hans123]

This question was previously asked and answered well.

https://www.mathworks.com/matlabcentral/answers/58111-how-to-convert-video-in-to-image-frames-using-matlab

[saeed ahmed]

Thank you for replying but do i have to pause video during analysis the image processing or it can keep working during processing

[Kevin Chng]

Hi, it is depend on your algorithm, the answer in the link will transform your video into a series of image.

The imwrite will generate the series of images in your current path.

Definitely, you may write an algorthm to transform selected frame to image when you pause.

[saeed ahmed]

Thank you but i use a live time video not a recorded one

[saeed ahmed]

if i want to apply that on this algorithm how can i do it

vid=videoinput('winvideo',1,'YUY2_640x480');
%Set the frames&RGB
set(vid,'FramesPerTrigger',inf);
set(vid,'ReturnedColorspace','rgb')
%Set timer of screenshoting of images per millisecond
vid.FrameGrabInterval=0.5;
%Acquiring video
start(vid);
%Set number of Frames in video
while(vid.FramesAcquired<=100)
    %To store extracted frames
    data=getsnapshot(vid);
    a=snapshot(vid);
    %extracting the Red color from grayscale image
    diff_im=imsubtract(1.3*data(:,:,1),rgb2gray(data));
    %Filtering the noise
    diff_im=medfilt2(diff_im,[3,3]);
    %Converting grayscale image into binary image
    diff_im=im2bw(diff_im,0.18);
    %remove all pixels less than 300 pixel
    diff_im=bwareaopen(diff_im,300);
    %Draw rectangular boxes around the red object detected & label image
    bw=bwlabel(diff_im,8);
    
    stats=regionprops(bw,'BoundingBox','Centroid','Orientation');
   
    %Show image
    imshow(data);
    imshow(a);
    hold on 
    %create a loop for the regtangular box
    for(object=1:length(stats))
        %saving data of centroid and boundary in BB & BC 
        bb=stats(object).BoundingBox;
        bc=stats(object).Centroid;
        be=stats(object).Orientation;
        %Draw the rectangle with data BB & BC
        rectangle('Position',bb,'EdgeColor','r','LineWidth',2)
        %Plot the rectangle output
        plot(bc(1),bc(2),'-m+')
        %Output X&Y coordinates
        a=text(bc(1)+15,bc(2), strcat('X: ', num2str(round(bc(1))), '    Y: ', num2str(round(bc(2)))));
        set(a, 'FontName', 'Arial', 'FontWeight', 'bold', 'FontSize', 12, 'Color', 'yellow');
        b=text(bc(1)-50,bc(2)+45, strcat('angel:', num2str(round(be))));
        set(b, 'FontName', 'Arial', 'FontWeight', 'bold', 'FontSize', 12, 'Color', 'blue');
    end
       hold off
end
stop(vid); 
%Flush the memory
flushdata(vid);
clear all;

Answer 1

[Image Analyst]

See my attached demo that will extract all frames, or you can process each frame one at a time.

[Image Analyst]

For live video, use snapshot() for a webcam object, and getsnapshot() for a camera that you're using with the Image Acquisition Toolbox.

[saeed ahmed]

can i make it like that ??

data=getsnapshot(vid);

a=snapshot(data);

[Image Analyst]

No. Startup imaqtool and then do a preview. Look in the window for what commands it's doing.

>> imaqtool

Answer 2

[KSSV]

vidObj = VideoReader('C:\Users\Public\Videos\Sample Videos\Wildlife.wmv');
numFrames = 0;
iwant = cell([],1) ; 
while hasFrame(vidObj)
    F = readFrame(vidObj);    
    numFrames = numFrames + 1;   
    imagesc(F)
    drawnow
    iwant{numFrames} = F ;
end

YOu can access the respective images of frame using iwant{i}.