Then resize each program’s window up and down by dragging the resize handle in and out so that the image goes from about 2cm wide to about 15cm wide and back, at a frequency of around 2Hz, for about 10 seconds. My method was simple: open both programs, and let them idle long enough that all CPUs and memory were mostly stable. CPU/Memory comparison – Darktable vs Monet vs Idle So, I did a fairly non-scientific comparison of a very simple action: resizing the window, and monitored the CPU and memory usage while I was at it. I didn’t get very far, and haven’t done much since, but I did just recently get the Demosaic operation to work correctly (Read more about that here, I based what I did on this article).

So, over the Christmas break I started working on an OpenGL-based, GPU-first photo editor (I’m calling it Monet). Also, it has much better driver support than OpenCL, especially on linux, thanks to Valve’s work on SteamOS. What I’m wondering is, why OpenCL? Open GL has a shader pipeline that is pretty much purpose built for processing 2D images, and for the slightly more complex tasks (like generating the histogram) it has had compute shaders since v4.3. In fact, even on my laptop, which has a Broadwell (ie 5th generation intel Core) series CPU in it, Darktable didn’t want to work with OpenCL. In fairness to Darktable, they do support OpenCL in some circumstances, but if it doesn’t work on the GPUs I have (2x Radeon R9 290x), which are now fairly old and have reasonably good driver support, you have to question whether it is worth it. RawTherapee doesn’t seem to do it at all, and Darktable’s is flaky. On Linux the use of the GPU in the most popular photo suites is spotty at best. Lightroom and Photoshop have some GPU acceleration, but apparently Lightroom doesn’t really benefit unless you have a big display (I guess they do all their rendering on a smaller view of the picture).

Apparently using the GPU to do all the heavy lifting isn’t something that the popular photography applications do. Seems a bit passé right? Well apparently not.

Rawtherapee vs darktable 2018