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Wikipedia:Reference desk/Archives/Computing/2014 July 9

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July 9

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Downloading and saving material from the internet onto a home desktop computer

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I have a question about computers. I am not that computer-savvy or tech-savvy, so please keep that in mind when replying. Thanks. If I go to a website and see a photo that I like, I can download (save) that photo onto my personal home computer (desktop). So, if that photo – for whatever reason – is subsequently removed from the internet website, I still have my own personal copy of it on my computer. Now, does the same hold true for videos? If I see a video that I like – and I want to have my own copy of it before it (potentially) gets removed from the internet – how can I download (save) that to my computer? Or is that not even possible? I tried a few steps, but I could not seem to make it work (or certainly not as easy as it is with photographs). Thanks. Joseph A. Spadaro (talk) 05:21, 9 July 2014 (UTC)[reply]

This is usually easy.
  • Try dragging the image to your desktop or into a folder.
  • Try right-clicking the photo, then "save as..."
  • The command can vary, depending on browser, but usually, there is an equivalent command in the r-click menu.
However, some sites protect their images, to reduce illegal re-use of their content. It doesn't work on the WP logo either, because the logo links to the main page.
Hope that helps. - ¡Ouch! (hurt me / more pain) 06:23, 9 July 2014 (UTC)[reply]
Actually, it works on the WP logo (which is not CC-BY-SA btw) if I use the left button (I'm using FF30); I tried right-button dragging. Fail. - ¡Ouch! (hurt me / more pain) 06:29, 9 July 2014 (UTC)[reply]
Thanks. But you misread my question. I said that I know how to do this for photos. I was asking about how to do it for videos. Thanks. Joseph A. Spadaro (talk) 07:04, 9 July 2014 (UTC)[reply]
It does depend a bit on the site your want to download the video from. For YouTube try doing a search for download youtube videos which will give you several different plugin and websites you can use. Probably safer to use a website as some of the plugins can be full of adds. This PC advisor article is relatively current. --Salix alba (talk): 07:22, 9 July 2014 (UTC)[reply]
Yes, it will depend on the site, Salix's links should be helpful. I'll add that some sites take extra steps to prevent you from easily downloading their videos. But, conceptually, anything that you can play on your screen (or speakers) can be captured and saved, see e.g. screencast. SemanticMantis (talk) 16:21, 9 July 2014 (UTC)[reply]
So, every individual site will require a different method? There is no "one size fits all"? Joseph A. Spadaro (talk) 17:25, 9 July 2014 (UTC)[reply]

The website www.dvdvideosoft.com has a fairly robust YouTube video downloader where (after installing the software) you can paste the URL of the YouTube video you want and hit download and it'll save it on your computer (you can also choose your output format and video resolution). For other websites, there are other methods (yes, I'm afraid there is no one single method that applies for all websites). However, the Internet Download Manager (another nifty software you can get by googling its name) adds a small plugin to your internet browser so that everytime you play a video on any site, it give your a small option button (which you get when you hover your mouse on the video) that lets you save it on your hard disk. As far as I remember, Real Player comes with a similar plugin too, which works only on videos, whereas Internet Download Manager can help you download images, videos, as well as music (even the background music playing on a site can be saved). Depending on your country, and how willing you are to bend the law, you can also obtain high resolution videos off Torrent websites (which are not, strictly speaking, legal. You've been warned.) Hope this helps. La Alquimista 18:52, 9 July 2014 (UTC)[reply]

Thanks. Is that Internet Download Manager free? Or requires payment? (And I am in the USA.) Thanks. Joseph A. Spadaro (talk) 22:38, 9 July 2014 (UTC)[reply]
Point of clarification: there is nothing illegal about using the Bit torrent protocol to "obtain high resolution videos." Some people do use torrents to obtain copyrighted material without paying for it, and that is illegal in many jurisdictions. But torrents can be used to share public domain video [1], open source software, and many other perfectly legal things. SemanticMantis (talk) 21:13, 9 July 2014 (UTC)[reply]
The critical thing here is how the video is presented on the web site. It can be just a ".avi" or ".mp4" file on the server that the browser downloads and displays - in which case, you can download it as a file. However, it's also possible for a server-side application to stream the video to you as your browser consumes it...so only a small section of the video is available at any given instant. To "download" this, you'd probably have to capture it frame-by-frame using a program like fraps. The same problem *could* potentially occur with still images. I've seen a couple of sites that attempt to prevent people from downloading a large image by chopping it up into teeny-tiny bits. When you right-click on what you THINK is the entire image and select "Save Image" - it saves a tiny postage-stamp sized chunk - and while you THINK you grabbed the entire thing, you actually only got a tiny piece. However, you can still do a screen-capture to see the image.
In the end it's a matter of your determination and technical skill versus that of the person who is trying to prevent you from doing just that. However, in such circumstances, you're almost certainly violating their copyright anyway...so you should probably "play nice" and not try too hard. SteveBaker (talk) 21:03, 10 July 2014 (UTC)[reply]

Thanks, all. Joseph A. Spadaro (talk) 00:16, 12 July 2014 (UTC)[reply]

Lock files to prevent deletion by anything other than my program VB.net

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I want to lock down some files in a folder to prevent other users from deleting/editing them. Then if my program wants to move or delete the file, it temporarily unlocks it, moves/deletes, then relocks it (if moved) to prevent deletion again. Essentially something/someone is deleting files on a drive and I need to do everything I can to stop it. It's an ancient IT system we are stuck with so it's likely the total lack of control or housekeeping over the years has casued something to go haywire.

I've read a bit about the filestream read-only property that would stop this by tricking the system into thinking the file is under use - Can I set this property without actually setting up a stream between the program and my file? Are there any other better ways in VB.NET? It needs to prevent file deletions/moves/edits by non administrators unless done so through the program.

Ultimate goal is to bit by bit lock a number of files and folders and only allow my program to move/delete files, this would ensure that only "approved" moves are allowed (I would use filesystemwatch to monitor "unapproved moves" by comparing a database of these with a database of "approved" moves). Thanks! 195.27.53.211 (talk) 07:47, 9 July 2014 (UTC)[reply]

Something like that is possible, but is there a reason you can't use file system permissions? There are plenty of little gotchas that could make a program cause strange bugs by locking files like that. If only non-administrators only have read access to the files then you won't need a program to enforce it. Katie R (talk) 12:07, 9 July 2014 (UTC)[reply]
Agreeing with Katie. File system permissions is our article, if you are using an OS in the *nix family, you'd want to read up on chmod. No idea how it works in Windows, it didn't even have permissions until relatively recently. SemanticMantis (talk) 16:17, 9 July 2014 (UTC)[reply]
"Relatively recently" meaning 1993 with NT 3.1. :-) I vaguely remember using per-user file permissions in 98 SE but I don't think the file system supported it so I'm probably wrong... Katie R (talk) 16:46, 9 July 2014 (UTC)[reply]
Ah, well NT wasn't exactly for average home users, was it? My reading of the the article is that Win2000 was the first mass-market WinOS to have a real persmissions system. That was long after I stopped using Windows, and I daresay "recent" in terms of OS history :-P SemanticMantis (talk) 16:59, 9 July 2014 (UTC)[reply]
It wasn't a consumer OS, but it made the feature available to those who needed it. Windows 2000 was the first consumer version based on the NT kernel, although it was also mainly a corporate version. XP was the first widespread consumer version with support. I do agree that those operating systems can be described as "relatively" recent in OS terms, but your average reader may not realize just how far back it goes. 1993 is starting to get back there though - 21 years old on a list that goes back 63 years. Katie R (talk) 17:27, 9 July 2014 (UTC)[reply]
Indeed in 1993 few OSes common nowadays existed in anything like their current form. The Linux kernel was still in a relatively early stage, after the (premature according to our article) jump to 0.9x but well before 1.0. OPENSTEP for Mach was still I think in an early stage (i.e. OS X was still a few years away). FreeBSD had just begun. Solaris (operating system) had just been introduced although of course the other Solaris SunOS had existed for some years (depending on your definition). Nil Einne (talk) 16:58, 13 July 2014 (UTC)[reply]
If this is a network with AD, you should be able to limit access to the directory to certain users. Alternatively, maybe you shouldn't be storing the files on a file system. Instead, create a database and store the files as BLOBs. A Quest For Knowledge (talk) 22:34, 9 July 2014 (UTC)[reply]

Keep in mind that if this were strictly possible, then malware could be written that could not ever be deleted through normal (i.e. not reformatting or anything) means. Instead I'd suggest file permissions as above.--Jasper Deng (talk) 04:08, 10 July 2014 (UTC)[reply]

Time Machine's schedule

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How does Time Machine (OS X) decide when to do what? I'm guessing that it goes like this:

if the last complete backup was at least a week ago:
while the backup drive is too full for a complete backup:
delete the oldest backup;
do a complete backup.
else if the last daily backup was at least a day ago:
do an incremental backup relative to the last weekly backup;
delete any daily backups more than a week old.
else if the last hourly backup was at least an hour ago:
do an incremental backup relative to the last daily backup;
delete any hourly backups more than a day old.

Is this close? —Tamfang (talk) 08:24, 9 July 2014 (UTC)[reply]

This page has some nice technical descriptions of various aspects [2]. SemanticMantis (talk) 17:10, 9 July 2014 (UTC)[reply]
Very interesting, though it doesn't touch on my question. —Tamfang (talk) 03:51, 11 July 2014 (UTC)[reply]

Unicode fonts with specific ligatures

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I'm taking notes on my computer and I want to use tone markup like ˧˩, which is composed of two unicode characters ˧ and ˩. Any fonts that work? unifont fails to join the characters, but whatever google chrome uses for its address bar (and this page although not the edit box) works. Chrome settings page claims it is using Arial/Times New Roman, but perhaps they are some special built-in versions, since they don't seem to work in xetex. How do I find fonts with support for specific ligatures or characters? --82.128.250.221 (talk) 18:03, 9 July 2014 (UTC)[reply]

After much searching I found two fonts: Charis SIL and Andika. They are both too thick for my liking, but then I don't have to use them for text, only these symbols. Unless I'm missing something big "font preview" sites are pretty useless when looking for rarely supported characters. --82.128.250.221 (talk) 23:44, 9 July 2014 (UTC)[reply]

Regarding gmail account security

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Dear Wikipedians:

While consolidating my gmail account security the following question occurred to me:

After someone hijacks my gmail account, wouldn't that person be subsequently able to change all the security settings, including cell phone number, rescue email address, backup addresses, security question, etc., etc.?

Is there such a thing as an "immutable" security object that I can set with my gmail account that can be fell back on in case my account is really, really hijacked? I am thinking things like my driver's license or social security number which does not change for the rest of my life.

Thanks,

70.27.87.193 (talk) 22:36, 9 July 2014 (UTC)[reply]

I believe they ask for another email address when you sign up. If somebody stole your account, and tried to change that, then they would send a notice to that alternate email address. If you then contacted Google, knew the answers to all the old security questions (which hopefully they keep), and they noticed that all your security info had just been changed, they might be inclined to agree that your account had been hijacked. StuRat (talk) 00:38, 10 July 2014 (UTC)[reply]
2-step authentication goes some way to mitigating your concern - now the evildoers would also have to steal (or hack) your phone as well as find out your password. -- Finlay McWalterTalk 00:40, 10 July 2014 (UTC)[reply]
Yes, I actually had just such an experience a couple of years ago. I had set up the email account some years earlier for someone else I regularly helped. Not sure how but someone else got into the email account. A day or so of correspondence with Google via the alternative address and all was fixed. HiLo48 (talk) 07:47, 10 July 2014 (UTC)[reply]
Note that most hackers won't want to permanently steal your email address. They are there to steal the information there, like your address book, or perhaps send out emails pretending to be you. Once they have the info and you've told everyone in your address book that the account was hacked, it's of no value to them. StuRat (talk) 15:30, 10 July 2014 (UTC)[reply]

Thanks for all your help. L33th4x0r (talk) 19:51, 12 July 2014 (UTC)[reply]

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