CytoPacq is a free web-based service for generating synthetic multi-dimensional images of cells and their populations in optical microscopy with accompanying reference annotations. The aim of the service is to provide an easily-accessible graphical interface for generating benchmark datasets suitable for testing and validation of bioimage analysis methods. Based on the difference from an automatically-generated reference annotation, one can easily compare the quality and accuracy of results of bioimage analysis methods, such as segmentation, tracking, or deconvolution.

Trivia: The web-interface name originates from words "CYTo", "OPTics", and "ACQuisition", where "cyto" originates from Ancient Greek word "kytos", meaning "cell" in english. The connotation of the name itself is "CYTOmetry PACKage".

Important Features

1 Each generated digital phantom is unique, due to the random nature of the employed computational models, hence the ability to (re)use it as a base for another simulation, with arbitrary configuration of virtual optical system and virtual acquisition device, is crucial for generating benchmark datasets.
2 Web-interface is working in standard web browsers, i.e. Chrome, Safary, Firefox, Edge, and Opera, with no requirements for additional modules like Java or Flash.


A web-based simulation framework capable of generating artificial microscopy image data fully in 3D+time. The simulated data imitate the image as if acquired using the fluorescence optical microscope.

Feel free to check this service and use the generated data!

Quick Start

After opening the CytoPacq web-interface in your browser, you are presented with the input form divided into three columns, digital phantom, optical system, and acquisition device, corresponding to the underlying modules. The question mark icon on the left side of every parameter row represents a contextual help, explaining the impact of the parameter and offering useful tips. Contextual help for a particular parameter can be accessed by hovering the mouse cursor over the corresponding icon. You can begin generating data in just two easy steps (see Fig. 1). First, you have to select the type of digital phantom that you want to simulate, e.g. a single cell with filopodia. And second, you have to click on the "Start simulation" button. Everything else will be handled in the background automatically by the web-interface simulation system.

Note: As the simulation process can take a substantial amount of time, depending on the chosen settings, we do not oblige you to leave the web-interface open in your browser for the whole process. To get back to your simulation later, you can either enter your e-mail (see row marked with an asterisk on Fig. 1) and use the uniquely generated link in the received notification, or you may bookmark the page in your browser.

CytoPacq web-interface
Fig. 1: Configuration form with simulation parameters in the CytoPacq web-interface.



The simulation process (see Fig. 2) begins by specifying desired configuration, which you can easily define by filling the input form in the web-interface (see Fig. 1). This configuration is subsequently passed to the appropriate simulator, depending on the chosen type of digital phantom. The simulation output then consists of synthetic images and accompanying reference annotations.

Simulation process
Fig. 2: High-level view (flowchart) of the simulation process.

Obtaining the data

As soon as the simulation is finished, you will be able to obtain the generated data from the download page (see Fig. 3). The download page contains previews of the synthetic images, (selective) downloads of the output data, and links to recommended image viewers. The image previews correspond to each stage of the simulation process, i.e. digital phantom generation, simulation of optical system, and simulation of acquisition device. You are able to download either complete archive, containing synthetic images of all simulation stages with reference annotations in TIFF or ICS format including generated configuration files, or any of mentioned separately. The recommended viewers, Viewer 3D and Viewer 4D, are our in-house developed tools for convenient browsing of 3D images and their sequences, respectively.

Note: The generated configuration files in INI or JSON format can be used as an input for our simulators, if you wish to install them on your computer and run them offline. More information about particular simulators can be found here.

Simulation process
Fig. 3: Download page with a finished simulation.

Additional Functionality

The following supplementary services are accessible from the main page.

Simulation process
Fig. 4: Access to data of previous simulations in "My CytoPacq".

Running the Software on Own Hardware

As described in QUICK START section, the simulation has three stages, i.e. simulation of digital phantom, simulation of optical system, and simulation of acquisition device. The CytoPacq web-interface utilizes three simulation modules for digital phantom simulation, CytoGen, OptiGen, and FiloGen. The simulation of optical system and acquisition device is implemented in OptiGen and AcquiGen module, respectively. All simulation modules are freely available in the form of preconfigured virtual machines, containing the simulation modules and corresponding source codes. More information about running the software on own hardware can be found on the respective web pages of each simulation module (see MODULES section).

Terms of use

The usage of datasets generated by the CytoPacq web-interface (or underlying simulation modules) is endorsed for scientific and educational purposes. The usage for any other purpose (e.g. commercial) is generally possible, but solely with the explicit permission of the authors. All generated data is free of charge and may be used as long as the CytoPacq web-interface is properly acknowledged by using the quotation of this form (may be modified only formally for the needs of individual publication purposes):

The dataset was created using CytoPacq web service[*] (

[*] Wiesner D, Svoboda D, Maška M, Kozubek M. CytoPacq: A web-interface for simulating multi-dimensional cell imaging. Bioinformatics, Oxford University Press, 2019. ISSN 1367-4803. 2019. doi:10.1093/bioinformatics/btz417.

More information is available here. In case of any questions, please do not hesitate to contact us (see CONTACT section).



The following papers describe the methods and principles of data generation used in the modules currently implemented in the CytoPacq web-interface.


The progress of work devoted to the simulator was incremental in order to meet actual needs of scientific projects No. 2B06052 and No. LC535 by the Ministry of Education of the Czech Republic, and the scientific projects GBP302/12/G157, GA14-22461S and GJ16-03909 by the Czech Science Foundation.



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