# Download the Jungfraujoch Viewer

`jfjoch_viewer` is a standalone desktop application, pre-built for Linux, macOS and Windows with
the Qt runtime included. The links point at the current release; the full list of what each release
ships is on its release page.

```{eval-rst}
.. jfjoch-downloads:: viewer
```

On a machine with an NVIDIA GPU take the **GPU** build: its embedded spot finding, indexing and
integration run on the card, and it also starts on a machine without one, on the CPU. The **CPU
only** build runs the same pipeline at lower throughput and is the smaller download. A V100 needs
the CUDA 12 build; the CUDA 13 builds start at Turing (T4) — see
[Release contents](RELEASE_CONTENTS.md#gpu-generations-and-the-nvidia-driver).

## After downloading

**Linux.** The archive has no top-level directory, so unpack it into a directory of its own, then
run the program from its `bin/`:

```
mkdir -p ~/jfjoch_viewer
tar xzf jfjoch_viewer-<version>-linux-cuda12.tgz -C ~/jfjoch_viewer
~/jfjoch_viewer/bin/jfjoch_viewer dataset_master.h5
```

The archive also carries the desktop entry, icon and D-Bus service file under `share/`, which the
desktop picks up when the archive is unpacked into a prefix it searches, such as `/usr/local`. The
Linux repositories carry the viewer as the `jfjoch-viewer` package as well
([package repositories](REPOSITORIES.md)).

**macOS.** Open the disk image and drag `jfjoch_viewer` onto the *Applications* shortcut next to
it. The image is signed and notarized by Apple, so it opens like any other application. Apple
Silicon only; Intel Macs are not supported.

**Windows.** Run the installer. The CUDA and CPU variants share one install directory and replace
each other, and are told apart in *Add/Remove Programs* as *Jungfraujoch (CUDA)* and *Jungfraujoch
(CPU)*.

Then **File ▸ Open** a Jungfraujoch or NXmx master file, a `_process.h5` written by Rugnux, or any
frame of a miniCBF, marCCD or SMV sweep; **File ▸ Open HTTP** follows a live collection from a
running broker. [jfjoch_viewer](JFJOCH_VIEWER.md) is the manual, with a
[guided tour](JFJOCH_VIEWER.md#a-guided-tour) of the four views most people use.

## From source

The viewer builds on Linux, Windows (MSVC and CUDA) and macOS; Qt 6 is the one dependency that
has to be installed first, everything else is fetched by the configure. See
[Building from source on Windows](JFJOCH_VIEWER.md#building-from-source-on-windows) and
[on macOS](JFJOCH_VIEWER.md#building-from-source-on-macos); on Linux configure the full tree with
`-DJFJOCH_VIEWER_BUILD=ON` ([Deployment](DEPLOYMENT.md#install-jungfraujoch-image-viewer)).