image_stack.lua - process a stack of images


This script provides another storage (export target) for darktable. Selected images are exported in the specified format to temporary storage. The images are aligned if the user requests it. When the images are ready, imagemagick is launched and uses the selected evaluate-sequence operator to process the images. The output file is written to a filename representing the input files in the format specified by the user. The resulting image is imported into the film roll. The source images can be tagged as part of the file creation so that a user can later find the contributing images.


  • start this script using script manager
  • select the images to process with image_stack
  • in the export dialog select “image stack” and select the format and bit depth for the exported image
  • Select whether the images need to be aligned.
  • Select the stack operator
  • Select the output format
  • Select whether to tag the source images used to create the resulting file
  • Specify executable locations if necessary
  • Press “export”
  • The resulting image will be imported

🔗Additional Software Required


Mean is a fairly quick operation. On my machine (i7-6800K, 16G) it takes a few seconds. Median, on the other hand takes approximately 10x longer to complete. Processing 10 and 12 image stacks took over a minute. I didn’t test all the other functions, but the ones I did fell between Mean and Median performance wise.


Bill Ferguson -

🔗See Also