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And this video of the riots, a program which gets from the user a timestamp and returns the frame corresponding

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to that timestamp in a video, a timestamp could look something like this.

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For example, zero zero four hours zero six four minutes seven point eighty seven four seconds.

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So we warned the timeframe at that time stamp in a video.

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Let's do this.

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I import almost CV and I create a video object using that video file.

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So it's a short three second video.

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One, two and three seconds.

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Right, then I'm extracting the number of frames here.

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So how many frames does the video have and how many frames are there per second?

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We want these two variables.

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These two numbers and I'll explain you why I need them.

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So let's run this to see what we get.

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Yes, a number of frames is 90 and FPSO frames per second is three.

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So three times three seconds we get 90 frames in total.

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And these are properties of open CV to give us the total number of frames when we use this gets methods

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and the frames per second.

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Again, when we use the get methods, so ways to get information about the video, what do we do with

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these numbers now?

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So the idea is that, for example, if we had a timestamp such as zero zero and zero zero minutes and

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zero two seconds, then we want to calculate what frame is this particular timestamp?

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Is it the 30 first frame, the 30 second frame, the sixth frame?

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Perhaps.

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So if it was one second, we know that in one seconds we have 30 frames so that zero zero seconds we

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have the first frame and the zero seconds we have the 30th frame.

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So in one seconds we have three frames.

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Therefore, at this particular timestamp, we have the 30 frame, we have the 60fps frame at this particular

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timestamp.

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So after two seconds, we have 60 frames.

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So basically we want to extract the frame, the number of frame for a timestamp.

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And we, of course, we can also do this with decimal seconds, such as eighty nine.

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We have to divide by the number of frames per second and so on.

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So let's do this.

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Let me show you what I think the formula should be.

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So first, I want to create a string that represents a timestamp.

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Later on, we're going to give this as inputs as an input function through the command line from the

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user.

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But from now, as we develop the program, let's just have it here.

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So zero zero four hours, zero zero four minutes, I'm going to say zero two point seventy five four

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seconds.

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So I'm not using minutes here because it's a very short video.

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So zero two point sixty seven should be within the limits of our particular video file.

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Once we have this string, we want to find a way to extract any of these members as a separate variable.

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So first, what I do is I would convert these into a list timestamp lists equal to timestamp dot splits

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with split.

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What you get is.

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A least out of a string.

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Oh, let me print it out.

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So now we have the items each separated as an individual object, so I a know we could go further and

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convert them.

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So let's create another variable floats that is equal to vessel list comprehension.

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So we want to convert each of those items.

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So floats I for I in time stamp list and see that this time.

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This list will have flows.

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You see, these are in quotes, but now.

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We have them as floats, as numbers, and that allows us to make calculations.

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I would go even further and stall each of these items in a variable.

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So let's say hours, minutes and seconds equal to timestamp list floats if you do that and you can then

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extract each of the items.

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So zero zero, you get the hours.

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And if you add minutes here minutes, it's also zero zero zero zero four hours, zero zero four minutes.

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And again, we also get seconds.

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Which is two point seventy five.

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So we have the time stamp as numbers.

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Now we want to get the frame number at that particular time stamp.

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How to do that?

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Well, let's say frame number is equal to.

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Hmm.

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So how if you do, how multiplied by three six zero zero, you get the number of seconds in an hour.

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So for example, one hour as 3600 seconds, two hours with half seven thousand two hundred seconds.

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And therefore, if we also multiply of IS by F.P. as we get something like, um, let's see if we have

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two hours times three six zero zero, we get seven thousand two hundred times thirty.

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We get the number of frames in two hours or in seven thousand two hundred seconds.

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In other words.

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So after two hours, we would encounter the frame number two hundred sixteen thousand right.

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Then we say plus minutes times, 60 seconds in a minutes times f p s.

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And finally.

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Plus seconds.

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Times FP s, that's the complete formula, so that's will give us the number of that frame that is in

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that particular time stamp using that frame number.

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We can use video that sets.

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So video is that object, which contains a video file.

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This gets as arguments the property i d, which is one with one you are saying that's you want to set

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the video at a particular frame.

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So this is a code for a property.

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And what is that frame?

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No, it is frame number this value here.

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So basically, what we're doing here is we open the video, but we don't play it.

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So we don't read the frames, we read the frames after we have set the starting point.

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So the starting point is this frame, which is something like it, depends on the timestamp.

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It would be something like the 60 or 70 or 80 frame of the video.

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So with two seconds, we have 60 frames and with two point seventy five, we should f around 70 75.

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Yep, now.

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So we said that the Sony points of that particular frame, and then we can apply that success frame

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to variables which will be populated with values from this method.

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So success will get a boolean such as true or false.

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If there is a frame at that particular point and frame will be the actual frame object, a number or

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a representing the image of that video timestamp.

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And finally, finally, we see two dots.

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I'm right and we give the name to the frame.

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File the image file, actually.

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So I'm going to do something like an f string frame that we could enter here, the hours and the minutes

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and the seconds.

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So these three variables and lustily dot jpg.

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And the second argument, so that is the first argument, the string representing the file name.

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The second argument should be the actual frame object, which is frame.

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So this one goes here, executes.

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And we have an image.

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So that is the frame.

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If you want to further improve the name of the file, perhaps you want to use.

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Some other variables here, which you can get from this object, so the time list, if you print the

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time list, time stamp list, you get these format.

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You see, with double zeros.

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So we could get to them.

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H h.

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And as as equal to timestamp list and then use H h here M M and SS Arun.

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And that is the next frame we got is the same frame, of course, but with a different name.

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And of course, you could then answer and inputs function here instead of having a static string.

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We could say inputs, answer time, stamp and age, age and SS formats.

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So we let the user answer.

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A time stamp.

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You see, the command line asks us, so let's say zero zero zero zero four minutes and zero two point

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twenty two four seconds.

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And we get that new.

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Frame.

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And that is the complete code for this video.

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Thanks a lot for following this, and I'll see you in the next one.