ChloŽ Agnew Forum

General Category => Off Topic => Topic started by: CWazyTom on January 19, 2017, 11:15:23 PM



Title: Caution about linking pics from Facebook
Post by: CWazyTom on January 19, 2017, 11:15:23 PM
I found out recently that links to Facebook pics are time-bombed (they expire after a while and the links stop working).

Here's an example of a link to a Facebook pic (without the img tags so you can see the URL):

https://scontent-yyz1-1.xx.fbcdn.net/v/t1.0-9/15055593_1496005117081356_68358868019580589_n.jpg?oh=3d85e76157271b0c4913890911f69573&oe=58C4D25F

That one is still working as of the time I posted this.

It will eventually expire.

Here's an example of an expired link.

Post:

https://scontent-yyz1-1.xx.fbcdn.net/v/t1.0-9/14344093_1263297053703640_1723051500194254711_n.jpg?oh=b64b91b5764285c443a0d8f650402bf4&oe=586FF932

If you try to browse to it, you'll get:
"URL signature expired"

If you try to enclose it in img tags on a forum, you'll get this:
(https://scontent-yyz1-1.xx.fbcdn.net/v/t1.0-9/14344093_1263297053703640_1723051500194254711_n.jpg?oh=b64b91b5764285c443a0d8f650402bf4&oe=586FF932)


If you browse to the picture on Facebook, you'll find it's still there, it just has a different URL signature, which will expire later on.

Old:
https://scontent-yyz1-1.xx.fbcdn.net/v/t1.0-9/15055593_1496005117081356_68358868019580589_n.jpg?oh=3d85e76157271b0c4913890911f69573&oe=58C4D25F

New:
https://scontent.fyzd1-1.fna.fbcdn.net/v/t1.0-9/14344093_1263297053703640_1723051500194254711_n.jpg?oh=b30bcf5193ccb722c5840f5083d0bc51&oe=590E2D32

The real trick is that the pic URLs have been randomized for privacy reasons, so:
- You can't really tell from the URL what post it came from
- You can't even tell who posted it, so you don't know what account to search to find the pic and get the new link.

So unless you documented what post it came from or are good at searching based on the post content / date, etc. it could be extremely difficult to find.

I've unfortunately got hundreds of pics on many forums linked to Facebook, so that's going to be a huge project to fix to find alternate (non-Facebook) URLs to the pic.

In the meantime, if you notice any of my pics that aren't displaying anymore, they're probably linked to an expired Facebook URL.

As far as I can tell:
- The links to the Facebook posts themselves are permanent and don't expire
- The links to Facebook videos don't expire
- Basically, any Facebook URLs that have "scontent" in the URL are going to expire eventually
- Twitter URLs appear to be permanent (not time-bombed)

Here's an example of the above pic I found on Twitter:
https://pbs.twimg.com/media/Csj065eWIAQGIwO.jpg:small

The other neat thing about it is you can add a special tag to the end of the URL to control the size:
:small
:medium
:large

Here it is in action:
(https://pbs.twimg.com/media/Csj065eWIAQGIwO.jpg:small)

Anyways, if any of your pics have mysteriously gone missing on forums, it's possible because they're linked to an expired Facebook pic URL.


Title: Re: Caution about linking pics from Facebook
Post by: Scott on January 20, 2017, 07:28:59 PM

I would strongly urge that anyone who wants to post pics in forums (any forums) should use a third-party storage site that specializes in pictures.

I use Photobucket but I do not recommend them at all.  They once were very good but have become difficult to work with.  I only continue to use them because, with literally hundreds of pictures linked through them in multiple forums, it would be far too much trouble to go and move the pics somewhere else.

When looking for a site, I suggest you pick (or, pic :D) a site that allows sufficient storage limits and produces true thumbnails of your images on their site pages.  My biggest problem with Photobucket now is that they only thumbnail part of the image, and looking at the thumbnail you cannot ascertain the proportions of the pic, which can be important when you are looking through your pages for just a certain pic.





Title: Re: Caution about linking pics from Facebook
Post by: CWazyTom on February 24, 2017, 12:07:49 AM
On a side-note related to Twitter and it's image size modifiers, it looks like there's a nifty little width attribute you can add to the img tag on the forum to restrict the width of a linked image.

In the following example, the image width is restricted to 500 pixels.

Code:
[img width=500]LINK_TO_YOUR_IMAGE.jpg[/img]

The forum appears to also resize the image height proportionally to maintain the aspect ratio.