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+---
+title: "xpra"
+date: 2020-01-15T18:29:57-05:00
+draft: false
+images: []
+---
+
+[`xpra`](http://xpra.org/) allows one to run persistent X applications on a remote host and display it on a local machine. It's a combination of [SSH X11 Forwarding](https://wiki.archlinux.org/index.php/OpenSSH#X11_forwarding) and [Screen](https://www.gnu.org/software/screen/).
+
+To get started you need to install the `xpra` package on both the server and client. On Ubuntu 18.04, this package isn't configured properly so one should use this PPA instead.
+
+```bash
+sudo add-apt-repository ppa:mikhailnov/xpra
+```
+
+To install,
+
+```bash
+sudo apt install xpra
+```
+
+Now you can from the client open up an application with one command
+
+```bash
+xpra start ssh:user@host --exit-with-children --start-child="executable"
+```
+
+If you want it to behave more like screen. Then on the server.
+
+```bash
+xpra start :100
+```
+
+Where you can replace `:100` with another high display number.
+
+Then you can run the executable,
+
+```bash
+DISPLAY=:100 executable
+```
+
+From the client,
+
+```bash
+xpra attach ssh:user@host:100
+```
+
+`xpra` has heuristics that determines the encoding of the images passed. You can however override it using the `--encoding`s flag to better tailor to your needs.
+
+- `rgb`: Raw pixel format that is lossless and uses compression. Best in high bandwidth environments.
+- `png` compressed, lossless, but CPU intensive. May result in skipped frames
+- `h264`, `vp8`, `vp9` are lossy formats that have tunable quality and speed parameters
+
+
+More resources:
+- [Arch Wiki](https://wiki.archlinux.org/index.php/Xpra)
+- [Ubuntu Wiki](https://help.ubuntu.com/community/Xpra)
+