How to extract specific frames from a video

Hey guys, does anyone know how to extract specific frames from a video? e.g, i want to extract 90, 150 and 160th frame and not any other frames. Does anyone know how to do it in a single for loop?

Right now i am using this code a=VideoReader('test.mp4'); for img = 1:a.NumberOfFrames; filename=strcat('frame',num2str(img),'.jpg'); b = read(a, img); imwrite(b,filename); end

But with this i can either extract all frames and not specific one.

Answer 1

[OCDER]

Try this one. Seems like read is no longer recommended, and it's replaced by readFrame. I changed the variable names too, to tell you a description of the variable as opposed to a, b, c, etc.

ReadObj = VideoReader('test.mp4'); 
CurFrame = 0;
GetFrame = [90 150 160];
while hasFrame(ReadObj)
    CurImage = readFrame(ReadObj);
    CurFrame = CurFrame+1;
    if ismember(CurFrame, GetFrame)
        imwrite(CurImage, sprintf('frame%d.jpg', CurFrame));
    end
end

[Shameendra Narayan Halder]

Thanks a lot. Code works and i get my desired framees

[Ashray Inala]

How do i get frames at a particilar time.. like 6 seconds 14 seconds and 20 seconds..

[Agostino Gibaldi]

Hi guys, the code works, but depending on the task at hand, can be slow.

Let's say I have a 2 hours video, and I want the frame at 1 hour and 59 min. With this approach I have to parse the whole video for nothing, just to get to the right point.

I could not find another wau, though... any idea from anyone?

Thank you,

A

[Felipe Palta]

Thanks a lot. Works perfectly. A thing more to add its if you want to extract all of frames from your video you need to change GetFrame vector as:

GetFrame = 1:1:TotalframesofYourVideo;

And TotalframesofYourVideo is the length Frames of your video that you can see click on ReadObj variable or:

TotalframesofYourVideo=ReadObj.NumFrames;

Best regards

Felipe

[Imranbasha Syed]

I had a query?

what does the Get Frame vecotr does?? Can u explain?