The latest version of the PixInsight Standard core application, 1.0.1.201 Beta 1, is now available for download:
http://pleiades-astrophoto.com/download/STD/index.html Along with a number of bug fixes, this new version includes the new LRGBCombination process. This release is entirely based on our customized version of Qt 4.1.1 and PCL 1.0.1.64 RC3.
LRGBCombination is an advanced software implementation of a rigorous LRGB combination procedure. This new process is destined to change the way most CCD color images are produced.
This is a summary of the main characteristics of LRGBCombination:
LRGB combination procedure performed within colorimetrically defined, rigorously implemented CIE Lab and Lch color spaces. The entire process is carried out with perfect isolation between chrominance and luminance, so there are no hue changes and no noise transferences between chrominance and luminance.
Individual RGB channel weights applied into a uniform dynamic range. When combining RGB raw data, pixel sample values are rescaled to define a uniform dynamic range, where the RGB combination yields pure white for saturated objects. This maximizes usage of the available dynamic range and guarantees a coherent color balance from the shadows to the highlights.
Luminance combine ratio. If necessary, luminance data can be combined with the luminance derived from the RGB data, by means of a transparency factor.
Luminance and color saturation transfer functions. Independent midtones transfer functions (MTF) can be applied to the luminance and to the
colorfulness component of the CIE Lch color space. The luminance MTF allows for a precise adaptation of the luminance to the available RGB data, which is essential to achieve the maximum possible color saturation, minimizing chrominance noise. The saturation MTF works cooperatively with a specific noise reduction algorithm (see below), allowing dramatic color saturation improvements with virtually zero chrominance noise.
High-performance chrominance noise reduction. A chrominance-specific, multiscale (wavelet-based) noise reduction algorithm has been developed by the Pleiades Development Team, and has been implemented in the LRGBCombination process. This noise reduction is applied at the final stages of the LRGB combination procedure, as part of the saturation MTF (see the preceding point).[/list]
Enjoy it!
The Pleiades Development Team
