I could be wrong, but I haven't been able to find a feature like this available in PlayOn at the moment. I thought that it would be helpful if there was a feature that would let a user manually add the URL of a video that they would like to play on their device if there does not currently exist a plugin to view it. This would be extremely useful if a user does not have the time/skill to program their own plugin and just wants to watch a few videos from an unsupported site when a plugin does not exist, or as a temporary solution during the times when a plugin may break due to a new version or change in website.
Basically, all it would be is an option in the PlayOn interface to add a specific URL of a video stream, which would then show up in the PlayOn Media Server in whatever device the user chooses under a "Manually Added" folder or something similar. I don't know how feasible this would be given the way PlayOn currently works, but I think it would be a useful feature, and I believe a similar option is available in some other media server programs.

The Podcasts Plugin from http://playonplugins.com may be able to do this though not specifically for a single URL to a single video source. Basically you tell it the "podcast" RSS feeds you're interested in and it'll present it in Playon.
Do you have a more exacting example of what you are trying to view?
Another thought here is to download the video file this URL is pointing out (you could use wget or extensions that some browsers have to download video content that is currently streaming) then use the Localfiles Facility build into Playon (or the LocalFiles plugin from http://playonplugins.com).
Thanks for the reply.
I will take a closer look at the Podcasts Plugin when I have time, but I am not sure if that will provide the actual functionality I am looking for.
I thought about the use for this feature because of a problem I ran into recently. I had been using the SouthPark Studios plugin for some time without any problem, until very recently it began only playing the last segment of every file. some others have had a similar issue on the forum but no word from the author yet on how to fix it or an ETA on any update.
So, as a temporary fix, I tried using a different media server application and found that is was able to add a single URL at a time like I suggested and watch the episodes from southparkstudios.com this way until the PlayOn plugin gets updated. I would much rather be able to do this using PlayOn, as I support and enjoy the project, so I thought I would suggest it as a feature in the future.
As I said, I will take a look at the podcast plugin, and perhaps it can provide the same functionality, but I still think this would be a useful feature for the program in general.
I don't see it as a useful feature only because adding URL's one at a time seems to me to be a painful way of doing it one at a time.
My understanding of this is that Playon looks at RSS feeds for video content. An RSS feed is simply an XML file that is produced to a certain parsible format that contain things like title and description, etc. A link can be provided.
If the link is a pointer to textual type information (e.g. a web page) then people tend to consider the RSS feed a news feed (think Associated Press). If the links refer to audio content then people call them podcasts (think radio show). Finally if the links point to video files people (tend to) call them vodcasts for "video podcast".
I believe that Playon sucks in the Hulu RSS feeds to figure out what you queue is, for example.
The Podcasts plugin is an end user configurable and generalization of this mechanism so you can specify your own set of RSS feeds (there's also something called a OPML file which I think acts as a hierarchical list of RSS feeds (or perhaps other OMPL feeds) to nest).
I'm not sure where on southparkstudios.com you are getting these URLs from (my current client blocks that site so I couldn't check) but perhaps there's an RSS feed that essentially gives you a list of all the shows or say all of the new episodes. If that's true you should be able to plug that into the Podcasts plugin and viola! South Park Episodes without the specialized South Park Studios plugin.
Good luck.
Another method is to use the LiveTV plugin with VLC. All the information on getting VLC working with the plugin is here:
http://www.playonplugins.com/index.php?topic=1513.0
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