Immix

Immix is an application that aligns and merges a set of similar images to reduce noise. It is available for both Linux and Windows operating systems. In low-light settings where the use of flash is not an option due to distance or lighting quality, a digital photographer can either use a low-ISO setting with a long exposure time or a high-ISO setting with a shorter exposure time. However, the former requires the use of a tripod to avoid blurry images.

The latter option is automatically chosen by most cameras, but this results in increased numerical noise. Fortunately, there is a third option that entails taking several images of the same scene with a short exposure time, aligning and merging them to decrease noise. The signal-to-noise ratio grows with the square root of the number of images taken. For example, a combination of 16 ISO 400 images has no more noise than a single ISO 100 image.

With Immix, users can load images into the program and have them automatically aligned using two specified reference points for small shift, rotation, or scaling correction. The images are then merged using the average method. Alignment is done using a cross-correlation algorithm on two zones specified by the user on the first image. The program uses the excellent FFTW library for lightning-fast correlation calculation for reference zones of up to 200x200 pixels.

To use Immix, users need to meet certain requirements such as having FFTW and Qt4 installed on their computers. The latest release of Immix includes several improvements such as the ability to use multi-core machines to their full potential, threaded image alignment to prevent freezing of the user interface, a new dialog showing image transformation data during alignment, a new Russian translation, and bug fixes, optimizations, and several new icons.

Overall, Immix is an incredibly helpful program for photographers who want to reduce noise in their images. It is easy to use, efficient, and available on multiple platforms.