Wikipedia:Reference desk/Archives/Computing/2015 April 14

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April 14

CCtv home security surveillance videos

Hi there! Does anyone know a link where cctv videos of home security surveillance cameras are available? Like videos in normal circumstances and videos while some one jumping in house or breaking in. I need these for my automated surveillance research work. I searched a lot but couldn't find, except activity recognition data sets that i dont need. Any help in this regard will be highly appreciated. I'm in so much need of it. Cheers

If I read your question right: You have no trouble in finding web cams on the internet. What it appears your asking for, is for filtering out web-cams solely dedicated to security (rather than the infamous Trojan Room coffee pot type of subject). I don't think you will have much joy because most people that buy a web-cam, set them up as per instructions and don't included any identifier to denote that it is a security cam. Good question though, as a universally recognized identifier would make it easy for neighbors to keep watch their other neighbor property whilst they are away.--Aspro (talk) 14:41, 14 April 2015 (UTC)

Thanks Aspro for your reply. I guess, I gotta record some videos by myself and then work on it :(

For home security cameras, there are several options:

1) Record continuously, and don't delete. The problem here is that it will fill up whatever device you use for storage, so you would need to keep putting in new storage devices. This was originally tapes, but more likely to be hard drives or even flash drives these days.

2) Record continuously in a loop. That is, after some period of time, it records over the old stuff. This way you don't have to worry about running out of space, but you have to stop it from recording over anything important or it will be lost.

3) Record only when motion is detected. This can make the recording media last a lot longer, and also makes it quicker to find anything of interest. The media could still record in a loop with this method. Problems are that motion detectors don't always detect all motion, or may detect incidental motion, like a tree branch waving in the wind.

Note that cameras are often connected to computers for storing and played the recordings. This can either be a permanent connection, or perhaps a flash drive on the camera can be removed and inserted into the computer when viewing is required. StuRat (talk) 18:01, 14 April 2015 (UTC)

That's all very well, but the OP is asking: Out of all the millions of web-cam broadcasts now available, how does one focus on just security web cams. Most of my searches end up with fish-tanks (of fish) and kittens (and other things I won't mention) – why-oh-why are there so many kittens on web cams? Many PhD's have put there all into providing us with web-cams that anybody can afford – but what do we see – kittens, kittens, and more ruddy kittens.--Aspro (talk) 19:29, 14 April 2015 (UTC)

It sounds like you're working in computer vision and you're looking for a corpus or a Training_set, is that right? Something that can be used for things like machine learning and feature detection, maybe facial recognition or threat detection? If so, you might find something useful here [1]. If you are part of a University, you should make use of your network there. If you are part of a company, same deal. If you are on your own, then we might be able to help more if you can better explain the question and your research goals. SemanticMantis (talk) 19:47, 14 April 2015 (UTC)

Every cloud has a silver lining. Your frustration is a business opportunity. One could convince sellers of web-cams to include a CD of software ( it gives it a unique Unique selling proposition). Los Angeles citizens (in say Skid Row could enter their location and make there security info available world-wide. Then, should anybody in say Japan ( a different time zone where people are not asleep at the same time as LA) see someone breaking in a property that has a web-cam code, they can report (via email) to the local LA law enforcement. The ability to speak English doesn't come into it. An email with web cam frames showing the brake in and location is all the LA police need. The web cam just needs to come with the software that allows the owner to easily set his web cam up as a security cam.--Aspro (talk) 20:09, 14 April 2015 (UTC)

Escape from Planet PDF Reader!

When I open a .pdf file in my Windows 8 .pdf reader I am trapped - there is no minimized or close button and the only options I can find are sweeping in all the Windows buttons and then reopening my browser on the right hand side or reverting to the Task Manager. What's the proper way to exit? Hayttom 14:27, 14 April 2015 (UTC)

I can't answer your question, but have you tried pressing ALT-f4 or ALT-TAB to get out of it? You could also try another PDF reader. There are plenty of free ones available. I use Sumatra PDF.--Shantavira|^{feed me} 17:31, 14 April 2015 (UTC)

If you are in full screen mode, the ESCAPE button (upper, left corner of keyboard) may get you out of that mode. As for why it starts in full screen mode, there must be a setting somewhere that can turn that off. StuRat (talk) 18:07, 14 April 2015 (UTC)

[ALT] plus 'F4'/'F11'. -- (Mr. Prophet (talk) 21:05, 14 April 2015 (UTC))

I'm not a windows 8 user, but isn't that one of the paridigm changes of the OS? That when you use an APP you aee IN the app, not you are on a desktop on which the app is running. As such there is no "full screen" vs "window" mode. It make it more like a tablet experience, rather than a desktop experience. I believe there are ways around it, such as the above mentioned free PDF readers, I personally use Foxit. Vespine (talk) 00:34, 15 April 2015 (UTC)

You may be right. Windows 8 = Yuk. StuRat (talk) 00:37, 15 April 2015 (UTC)

Thanks, everybody. First, I just noticed that when I open a .pdf, I *do* have a minimize and a close icon in the top right corner. But as soon as I mouse near to the top of my screen without aiming right for those icons, that top bar that contains them disappears forever. OK: Alt-F4 works perfectly. (I have an inkling that this is a basic Windows trick everybody knew except me.) Alt-F11 does nothing. Alt-TAB works perfectly. (See previous inkling.) ESC does nothing. I can live with Alt-F4, but I might also look at other viewers. Or apps. Hayttom 01:59, 15 April 2015 (UTC)

Resolved

Apology, I meant only 'F11', my careless mistake -- (Mr. Prophet (talk) 06:05, 15 April 2015 (UTC))

There's also an option for Windows 8 to display more like "Classic Windows", I believe. Others can tell you how, if you are interested. StuRat (talk) 02:14, 15 April 2015 (UTC)

I don't use Windows 8, looking forward to Windows 10 in the near future when I buy a new computer! Touchscreen hopefully! its already out now... -- (Mr. Prophet (talk) 06:05, 15 April 2015 (UTC))

Do you mean pressing the 'Windows' key on the 'keyboard' on Windows 8 Operating system? - Mr. Hayttom, try pressing it; wait for it to function... -- (Mr. Prophet (talk) 06:05, 15 April 2015 (UTC))

3 points. One is that the default PDF reader on Windows 8 is generally Microsoft's Reader which is a Metro/Modern UI application. If you set your PDF reader to be a desktop one, like Adobe Reader or the million others out there, then yes, this won't happen.

Other than the start screen, when using desktop application you should basically find no real significiant difference between Windows 8/8.1 and Windows 7, except that Windows 8/8.1 may perform better on lower end hardware. Contrary to the claim above there's no need to change anything do display a more classic Windows (unless by that you mean like XP or something) for anything but the start screen. And there's only really a small amount you can do within Windows 8.1 itself to change the start screen to be more traditional. You need to use third party apps if you want a completely traditional start menu, at least until Windows 10.

Presuming you're using Windows 8.1 update 1 (it sounds like you are otherwise you won't have the close or minimise button but in any case you should be), on Modern UI apps you should be able to move your mouse above the screen and the close and minise buttons should re-appear. You can also move your mouse to the top of the screen and drag the window all the way to the bottom of the screen to close it. To minimise it, just navigate to another window. Windows key+t should reveal the taskbar. Theoretically, moving the mouse to the bottom of the screen should also reveal the taskbar in Modern UI apps, but I've found this isn't totally reliable as have others [2]. Alternatively, you can scroll to the bottom left or top left of the screen to display the Metro/Modern UI start menu button and switch window menu. Finally you can use standard switching window hot keys (alt+tab, windows key+tab etc) as normal.

Nil Einne (talk) 09:00, 15 April 2015 (UTC)