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So welcome back to the section on working with video.

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So we're going to open the second book here to listen.

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But before I do, I just want you to note something.

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Notice that the first notebook we opened is in has a green icon here.

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This green icon indicates that it's still running right now.

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You can check it in your running tab and you can see it's still here, and you can resume this notebook

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by opening it, opening it here and going back to the lesson.

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When you close, the tab here doesn't actually terminate the notebook.

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It's still running.

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So if you wanted to shut it down, just press shut down here and you can see changes back to agree icon.

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So let's open the second book called Opening Video Files, and we'll take a look at this lesson.

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So let's zoom in a bit so you guys can see clearly.

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So in this lesson, what we're going to do?

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We're going to open this video here called Tramadol MPEG four, and we're just going to play it and

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notice that there's some could here that I'll explain to you now what is part of it?

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What his piece does is that remember, every time we read a frame from the video, that cup is opened.

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So every time we read a frame from this and while they do, the copies opened.

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We get the frame here and they get ripped as well.

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Read is a boolean that tells us whether or not the frame was read correctly.

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So if it wasn't read correctly, which means that we have come to the end of a video file, it would

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break the loop and exit and close the window and released a camera here.

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Alternatively, if we wanted to close this video, you can press Q.

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That's what it gives us.

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The it maps the key value to the actual digit of what we keys equates to being equal.

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And then once this is this condition is met, it breaks to loop here.

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So let's run this code and take a look at it.

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So again, the window opens behind the scene and this is a drummer, one of my favorite drummers.

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Matt, you got his last name, though.

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Matt McGuire, so you can look him up in YouTube, he's quite good and you can see this beach ball has

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come up again, and that's because a Mac systems, whenever we try to and this here doesn't actually

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close the window.

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So that's unfortunate.

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But that's OK.

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We can work with this for now.

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So here's another thing to think about how do you check a video stream or video file is correct?

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Or is it was off the correct format and loaded properly before actually playing the video?

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So what you can do is use the cap is opened for of function here.

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This tells us if it's not opened successfully, which means that we can't access a frame from the video

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it will exit the program.

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OK.

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Well, you can just review areas era as well is exception.

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However, whatever you prefer to use, I think in Python this is probably not the best coding practice

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to use, but nevertheless it works and we will use this here.

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So let's look this and you'll see the video again with Matt McGuire drumming his heart out.

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He's really, really impressive drumming.

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He actually drums for The Chainsmokers on tour right now.

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So you can see at the end here at the end of the file it, which is that there's no return false.

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So the stream is now stopped and you can see it's printed out here.

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So let's just quit these.

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No.

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This notebook will have to be restarted.

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Actually, it's restarts by itself.

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Great.

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So now let's take a look at the cup.

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Don't get it.

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What is that?

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This is a method where we can actually access information about the video file itself here.

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It has 18 elements in this list of capture, and we can see we can print them out right here.

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So you can see it includes all sorts of information about the video, and you can immediately see 640

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by it for 60 is a resolution.

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So if you wanted to actually see what each number denotes, you can check it out on the open TV documentation.

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However, for now, it would just take it.

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We just need to know that this is two frames per second.

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Some of these relate to bitrate as well and codec information, and a lot of these aren't really used.

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Consider just zeros here.

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So that's it.

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For this lesson, we'll stop there, and then we'll go on to saving and recording videos and open TV,

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which you would have seen before in the cloud, but notebooks that we use.

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However, we'll just define it here as well.