Universal Media Server is a Java-based server which can stream video, audio or pictures to any DLNA device.
Supported devices include Sony PlayStation 3 (PS3) and PlayStation 4 (PS4), Microsoft Xbox One and 360, many TVs (Samsung, Panasonic, Sony, Vizio, LG, Philips, Sharp), smart phones (iPhone, Android, etc.), Blu-ray players, and more.
The program is powered by assorted other open-source applications - FFmpeg, MEncoder, tsMuxeR, MediaInfo, OpenSubtitles - but you don't need to have any of these beforehand. Universal Media Server installs and configures them itself.
When there are setup steps to consider, they're fairly straightforward: choose the speed of your network, do you want to hide the advanced settings, and so on.
Once it's up and running, all you really need to do is set up folders you'd like to share: music, pictures, whatever.
Other systems on your network can then access them via port 9001 on your computer's IP address (just enter an address like 192.168.1.x:9001 in your web browser).
You can also discover other devices from the server and browse their media, for example the videos on an iPad.
As with anything else network-related, there's plenty of scope for problems, but fortunately you get a lot of setup and troubleshooting documentation to help figure them out.
What's new in 6.7.3 (see full changelog for more)?
Improved support for AVI and MJPEG
Improved general DLNA implementation
Fixed duplicate entries in transcode folders
Fixed logging in macOS
Fixed menu name in macOS
Added renderer configuration for conversion of 3D video to 2D
Added support for Fetch TV
Added support for Onkyo TXNR8xx
Improved support for Cambridge Audio Azur BD
Improved support for OPPO BDP
Improved support for Panasonic VIERA TXL32V10E
Improved support for Sony BRAVIA 5500 and EX TVs
Improved support for Sony SMP-N100
Improved support for Sony STR-DA5800ES
Fixed album art for Onkyo receivers (and probably others)
Fixed support for Xbox 360
Updated MediaInfo to 0.7.97, which:
A powerful media server which is exceptionally easy to set up and configure.