Any word on the timeline to implement CUDA utilization?
Not one word, but three: time, time, and time. Aside from Carlos Milovic, who is working on critical development projects such as TGV, and a little bunch of developers that are actively working on very specific areas (Mike Schuster, Andrés del Pozo, Georg Viehoever, Klaus Kretzschmar, and a few others), I am completely alone. I just cannot afford stopping everything for months to start a CUDA support implementation in PixInsight. I must work on hundreds of priority tasks, including bug fixes, compatibility problems on Windows, OS X and new Linux desktops, user support, forum and website maintenance, new tools, improvements to JavaScript and C++ development frameworks, GUI improvements, and testing everything. Not to mention documentation, which is our eternal pending task, and writing development and image processing tutorials, which are essential tasks that I have had to abandon completely.
That said, the importance of GPU acceleration in an application like PixInsight (and, to the same extent, any 2D, high-level image processing application) is being highly overestimated IMHO. It's true that a relatively simple implementation would speed up significantly a number of tasks (basically, any task whose running time is dominated by convolutions), but the neat benefit wouldn't be really important for most users. It is also true that there are other important CPU-intensive tasks, such as TGVDenoise for example, which would benefit significantly, but this would require a complex implementation and hence a lot of time.
We have many important priorities before GPU acceleration. For example, a critical process such as StarAlignment would benefit enormously from a high-level CPU parallelization, similar to the one that I implemented for ImageCalibration. This would accelerate image preprocessing by at least one order of magnitude, especially for large data sets. Another example: an integrated C++ compiler. This will simplify deployment of open-source modules, making C++ development as easy, robust and platform-independent as JavaScript development in PixInsight. Currently I prefer to invest our very limited resources in writing and testing new exciting tools, such as TGVRestoration and new background modeling and image registration tools. The XISF project is also very important---despite many people do not, or do not want to, understand it.
This is not to say that I don't want to implement GPU support in PixInsight. It's just the opposite, but unfortunately it is something we cannot afford at present. Hopefully in 2016, but I'm not sure.
