Hera Version 0.3

This is a screenshot from Hera Version 0.3, the latest pre-release version of my astrophotography processing software. And this 90-s YouTube video shows how I have used Hera to process an image of the Tadpoles Nebula IC 410 that I captured in November 2021.

For the graphical interface, there is a sequence of steps down the left-hand side, each specifying another step as input with optional blending mask and opacity; each step is an instance of a specific processing tool, the settings of which are editable in the panel on the right-hand side. The output of the selected step is displayed in the center, with its histogram at the bottom. Changing a tool setting in any step automatically propagates through all subsequent steps.

Here is the final image at the end of the video:

About Hera

The design principles of Hera are to:

• offer a range of tools that are specifically suited for processing astrophotos;
• including some of the latest cutting-edge ones from the scientific literature;
• have a fully-editable and re-computable process history;
• be fast, making use of parallel processing and speed-optimized algorithms wherever possible;
• not save large intermediate images, and instead only the ‘sequence’ of steps that gets you to the final processed image (so that means small files);
• have a user-friendly interface.

Tools

Currently available tools include:

• À trous wavelet transform
• Background gradient removal
• Background neutralization
• Color calibration
• Color saturation
• Fast contrast-limited adaptive histogram equalization (CLAHE)
• Cropping
• Histogram transformation
• Iterative masked stretching
• Mask merging
• Morphological transformation (which also does star reduction)
• Fast non-local means (NLM) noise reduction
• Range masking (based on hue, saturation or luminance)
• Star masking (based on the wavelets transform)
• Subtractive chomatic noise reduction (SCNR)
• Unsharp mask

Short-term future development includes (in some kind of order of priority):

• Denoising with deep learning and convolutional neural networks
• Improved narrowband processing
• Color calibration based on catalogued star color

Technical details

Hera is all written in C++. The graphical user interface (GUI) is written in wxWidgets, which means it is cross-compilable for Mac OS X and for Linux/Unix. Image handling is in OpenCV, which mainly just provides the data structures and barely any useful library functions (its 32-bit floating-point capability is dire).

Public release

If there is enough interest, I will offer a basic version of Hera 1.0 for free, and also sell licenses for the full version, probably on an inexpensive annual subscription basis (like SharpCap). I probably won’t be ready for this for about another six months, at least… I keep adding new capabilities! I probably also need to record some instructional videos or write some documentation.

If you are interested in this project, and want to be kept up-to-date, or you are interested in possibly helping with testing at some point in the future, leave a message below.