CARTA key features

CARTA adopts a client-server architecture which is suitable for visualizing images with large file sizes (GB to TB) easily obtained from ALMA, VLA, or SKA pathfinder observations. It is impractical to process such a huge file with a personal computer or laptop. In a client-server architecture, computation and data storage are handled by remote enterprise-class servers or clusters with high performance storage, while processed products are sent to clients only for visualization with modern web features, such as GPU-accelerated rendering. This architecture also enables users to interact with the ALMA and VLA science archives by using CARTA as an interface.

CARTA has two flavors: Desktop version and Server version. The former is suitable for single-user usage with a laptop, a desktop, or a remote server in the "remote" execution mode. The later is suitable for institution-wide deployment to support multiple users with user authentication and addtional server-side features.

Memory-efficient when loading images

With ~1 GB of ram, a 16000 pixel x 16000 pixel image or a 16000 pixel x 16000 pixel x 1000 channel cube (~1 TB in size) can be loaded in seconds.

Parallelization and GPU-accelerated rendering

Parallelization with CPUs is invoked in data processing. GPU-accelerated rendering is adopted for raster images, contour images, and catalog overlays.

Progressive and responsive update of spectral profile

Region spectral profiles are updated progressively and may be cancelled at any time for a better user experience.

Customizable and reusable GUI layouts and preferences

CARTA is equipped with a highly customizable and reusable graphical user interface for various use cases.

Efficient catalogue processing and rendering

Catalogues with a million sources can be loaded and rendered in seconds. Catalogue files are processed with parallelization techniques and are rendered with GPU acceleration.

Efficient visualization with HDF5 (IDIA schema) images

The HDF5 format with the IDIA schema improves the user's experience of viewing large image cubes significantly.


Release plan

Current release

The current release is v1.4, released on 17th of September 2020, with the following features:

  • Catalogue support
  • Shared region analytics
  • Animation playback improvement of raster and contour images
  • Profile smoothing
  • Moment map generator
  • Spectral line query
  • Server authentication and deployment improvements
  • File browser improvements
  • Bug fixes and performance improvements

Next release

The next release will be v2.0 with the following new features:

  • Publication quality image output
    • Support high resolution png
    • Support a color bar in the image viewer
  • Preparations for the PV generator
    • Support rectangular pixel rendering
    • Support line region type
    • Display xy labels and ticks properly for a position-velocity image
  • File browser improvements
    • Support CASA image types: concatenated, componentlist, LEL
    • Support integer, complex and boolean image types
    • Support pv images
    • Show correct beam for multi-beam images
    • Support for fz (compressed FITS) and fits.gz
    • Flexibility with non-standard FITS header
    • Open multiple files via file browser
  • HDF5 enhancement
    • Support mip-mapped datasets including spatial and spectral profile requests
    • Accelerate moment map generation with swizzled dataset
  • Catalog enhancements
    • Enhanced marker-based visualization
    • Support catalog overlay on spatially matched images
  • Polarization enhancement
    • Support loading individual Stokes images for visualization with the Stokes analysis widget
    • Show polarization intensity and angle “images” on the fly (from Q, U, and I if fractional) and support Stokes V
    • Support flux density and other stats in Stokes analysis tool
  • Spectral line query
    • Support filtering and sorting in the spectral line query table
  • Spectral profiler
    • Profile fitting
    • Viewing multiple profiles in one widget
  • Basic Python scripting interface

Future release

This is a non-exclusive list of features we would like to add in subsequent releases, but they are not 100% decided upon yet and depend on feedback from users, resourcing etc.:

  • Polarization contour and images
  • Interactive CLEAN with CASA (TBD)
  • Multi-panel view
  • Channel map view
  • Position-velocity map generator
  • Server collaborative tools
  • Vector field (polarization) rendering
  • Volume (pseudo 3D) rendering
  • Profile, histogram, and image fitting tools
  • Scripting interface (Python3)
  • Three-color blender
  • Angular distance measuring tool
  • Image source finder
  • VO service (image and catalog)
  • Image arithmetic

Please VOTE your top-five features here.


Desktop version

Suitable for single-user usage with a laptop, a desktop or a remote server in the "remote" mode.
Current release: v1.4 (2020/09/17)


10.15 Catalina
10.14 Mojave


Red Hat



Red Hat

(remote mode only)


Installation instructions for macOS and Linux are here.

The user manual is available here.

Previous releases of CARTA can be found here.

Should there be any problem, please contact us, or submit an issue.

Server version

Suitable for institution-wide deployment to support multiple users with user authentication and additional server-side features.
Current release: v1.4 (2020/09/17)

Please follow the instructions here for the server deployment. In case of problems, please contact us.


Project information


CARTA is mainly built in C++, TypeScript, and JavaScript, and with the following third-party libraries. Check out the codebase on Github.


Please use the DOI 10.5281/zenodo.3377984 as a citation when using CARTA for publications.