Install

ITASC is a napari plugin, so running it takes three things: a Python, an isolated environment to keep that Python clean, and the ITASC package installed into it. One tool, uv, does all three. You do not need Python already, you do not need to know what an environment is, and nothing here touches software you already have.

This page is written for a Windows machine with nothing installed yet. macOS and Linux differ only in the first command, noted where it matters. It installs the full pipeline, itasc[all]; installing a single stage instead changes one word in the final command, listed under Other distributions. The uv setup is the same for every one of them, so start here.

Already have a Python environment? Run uv pip install "itasc[all]" (or pip install "itasc[all]") into it and jump to Launch and check. The rest of this page sets up that environment for you.

Install uv

uv is a single small program that installs Pythons, builds environments, and installs packages. Install it once and it manages the rest.

On Windows, open PowerShell: press the Start key, type PowerShell, and press Enter. In the window that opens, paste this line and press Enter:

powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"

On macOS or Linux, open a terminal and run:

curl -LsSf https://astral.sh/uv/install.sh | sh

The installer edits your PATH, which the terminal only reads at startup. Close this terminal window and open a new one, then confirm uv is there:

uv --version

A version number means uv is installed. A “command not found” means the terminal is still the old one: close every terminal window and open a fresh one.

Install ITASC

One command installs everything:

uv tool install napari --with "itasc[all]"

This downloads a Python for you, builds an isolated environment, installs napari together with ITASC and every stage’s engine (Cellpose-SAM for segmentation, the Ultrack solver for tracking) into it, and puts a napari command on your PATH. The [all] extra is what pulls in those engines; without it you get the plugin but not the heavy machine-learning dependencies.

The download is large: the segmentation engine ships PyTorch, which is over a gigabyte, so the first install runs for several minutes and is quiet while it works. Let it finish.

The environment it builds is isolated: it will not disturb any other Python on your machine, and removing ITASC later is one command (see Update and remove).

Before the first release. ITASC is not yet published on PyPI, so the command above cannot find it yet. Until the release, install the current version straight from the source repository, which produces the same result:

uv tool install napari --with "itasc[all] @ git+https://github.com/ArturRuppel/ITASC.git"

Launch and check

Start napari from the terminal:

napari

An empty napari window opens. In its menu bar, open Plugins → ITASC → ITASC. The ITASC workflow widget docks on the right of the viewer. That widget appearing is the check that the install worked.

📷 Screenshot: the napari window just after opening the plugin, the ITASC workflow widget docked on the right with its stage sections collapsed.

If napari reports “command not found”, the terminal has not picked up the new PATH: close it and open a fresh one. If napari opens but ITASC is missing from the Plugins menu, the --with "itasc[all]" part did not take: rerun the install command from the previous section.

With the plugin open, the full-app guide walks through the project layout on disk and the five stages in order.

GPU

The GPU matters only for the distributions that segment: itasc[all] and itasc-cellpose. The tracking and aggregate stages run no deep-learning inference, so this section does not apply to them.

ITASC runs on the CPU with no extra setup, and everything works there. Segmentation with Cellpose-SAM is the one heavy step, and on an NVIDIA GPU it runs many times faster. The GPU is used automatically whenever PyTorch detects a CUDA-capable card, so on most NVIDIA machines the default install already uses it.

If segmentation stays slow and you have an NVIDIA GPU, PyTorch has fallen back to CPU and needs a CUDA build matched to your driver. Two guides give the exact command for your setup:

  • PyTorch’s Get Started selector, which builds the install command for your CUDA version.

  • Cellpose’s GPU installation notes, which cover the same for the segmentation engine specifically.

Install the PyTorch they specify into the same environment, and segmentation picks up the GPU on the next run.

Other distributions

The command above installs the whole pipeline. Each stage also ships on its own, for running one job on its own data. The uv setup is identical; only the package in the --with changes, along with the extras that carry its engine:

# Sparse cells: Cellpose-SAM segmentation, then laptrack linking
uv tool install napari --with "itasc-cellpose[cellpose,laptrack]"

# Foreground/contour maps to Ultrack tracks, plus correction
uv tool install napari --with "itasc-tracking[solve]"

# Tracked labels to contacts and T1 events (HDF5, CSV)
uv tool install napari --with "itasc-aggregate"

The extras hold the heavy engines, so you can drop one when you do not need it: itasc-tracking without [solve] browses and corrects existing tracks but cannot run the Ultrack solver, and itasc-cellpose without [cellpose] keeps the tracking helpers but not the segmentation model. Each distribution’s guide, linked from the overview, says which extras its widgets need. Launch and check works the same: open napari, then open that distribution’s widget from the Plugins menu.

Each command sets up the single napari tool with that one distribution, so installing a second one replaces the first. To have every stage available at once, use the full app, itasc[all].

itasc-core is a library

itasc-core is the shared substrate, not an app: you import it from your own Python rather than launch it, so it belongs in a project rather than in a tool. In a uv project, add it as a dependency:

uv add itasc-core

The core guide covers what it exposes.

Update and remove

ITASC is registered as a uv tool under the name napari. Update it, engines and all, with:

uv tool upgrade napari

Remove it and its entire environment, leaving the rest of your system untouched, with:

uv tool uninstall napari