HDR image to LDR using edge-preserving multiscale decompositions (opens in new tab)

What would you train it on, without already having an algorithm you consider 'good'?

Ubuntu/Debian users, put this in ~/.local/share/nautilus/scripts to have it accessible from your right-click menu:

  #!/bin/bash
  align_image_stack -a BATCH -C $(echo -n "$@") && enfuse -o ~/Desktop/align-and-fuse-$(date '+%Y-%m-%d-%T').tif BATCH*.tif && rm BATCH*.tif

Prerequisites are align_image_stack and enfuse packages (Hugin users already have them or do it manually) and after that, just shoot bracketed and multi-select each set of bracketed photos > right-click > Scripts > run script. A timestamped finished image in TIFF format will output to your desktop. I usually open these in Darktable for minor post processing, then final export to JPEG.

Was thinking the same thing.

Essentially the person is saying they don’t own an SLR (digital or film) or a mirrorless camera, don’t own a smart phone, and don’t have a pocket point&shoot made in the last ten years or more.

You need to be able to change only shutter speed or ISO, while holding aperture constant. That's not a problem for phones, because they're almost always fixed aperture anyway. And of course any DSLR or mirrorless camera can do it. But some point-and-shoot cameras won't have this capability, they'll want to be fully automatic, not giving the photographer that specific control.

Why not a single exposure? My camera (Nikon D750) shows up as having 14 stops of DR on DxOMark and IRRC a typical monitor in ambient condition is 8-9 stops. I haven't tested any of this though. Any in-camera JPG processing is applying a tone-mapping function to compress the range. Is the HDR label reserved for an image that has more range than the human eye can see and not necessarily the viewing device?

They need some method for keeping the camera in the same spot, and (roughly) pointing in the same direction.

A smartphone without a dedicated funcion probably has too much delay between shots for HDR. Same for point-and-shoots without a tripod mount.