Median stacking using G'Mic in GIMP

@afre had you hit the buttons in point 8 to 10 from the tutorial?

It crashes at the crop step.

The current workaround is to remove the metadata and then input the lens data. Doing a quick web search reveals that this is (related to) an old problem. Someone should report this to the proper channels.

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  1. I opened the pictures to Hugin
  2. I created controlpoints with Hugins CPfind
  3. I Optimized with Positions (incremental, starting …) (= first tab), then Calculate
  4. I opened the Fast Preview panorama, opened Projection, I pressed Fit button, I selected Rectilinear projection, I pressed Fit button, I picked Crop and then Autocrop.
  5. Go to Sticher, tap Calculate Optimal Size, select only No Exposure Correction, Low Dynamic Range, press Stich button, select Folder, and Save.

You can open the resulting tif images to Gimp as layers. Images are pretty big, so Gmic / median can be in trouble. Perhaps images should be converted to jpg. I tried to find a way for Hugin to save images in jpg format, but I did not find it.

Second chance to step 5:
Go to Sticher, tap Calculate Optimal Size, clear all options, open the Output menu and then select User defined output sequences/Normal panorama with layered TIFF output, select folder and save.

Obtained layered tif image is pretty large, it can be opened to gimp and use gmic / median, but at least my computer memory might be too small.

So final update here: I can’t change the name on the USERS folder in order to remove the space. So I made a new account on my machine with no spaces and was able to have align_image_stack add control points to my images.

I also changed from enblend to the built-in blender and was able to get the stack to align without any errors.

It sucks that I can’t somehow use hugin from my main acccount; it would be great if someone with an Ubuntu One account could let them know about the bug. Till then I’ll just switch accounts back and forth.

Thanks again for all the help!

  1. You could try to set the temp file path in the preferences. You can find it File->Preferences Tab:Filenames.
  2. What is the link for reporting hugin bugs?

@rpac78 Do you need blended picture of all pictures? If you do not need it then why blend them? You can use Hugin to get only aligned pictures and use them in Gimp/Gmic.

Can I ask why so meny pictures, what’s the goal?

  1. Good idea but didn’t work: the problem is with the space in the command line not with the listing of temp file paths because hugin uses the user specific path for temp app data.

  2. I think you report bugs on their launch pad page: Bugs : Hugin

No worries, I’m glad you asked.

Yes I need all of them. I sometimes use or need more. I like to do long exposures and by stacking these photos and doing a median blend, it’s simulating like I had shot it with a longer shutter speed.

For example these photos were shot at 1/6th of a second. If I stack 10 of them, then it’s 1/6th times 10 which is a full second. So now I have a photo with a shutter speed of 1 second without the handheld shakiness of 1 second…

I have done this to simulate 5, 10, even 30 minute long shutter speeds.

There are many other benefits to doing long exposures this way. If you’re interested look up exposure stacking or median blending.

To finally put this to rest, I posted this problem into the hugin Google group and got this response:

Hello,

I have a problem with the addition of control points in hugin. The username of my computer has a space in it and it seems that hugin can’t handle that and throws up an error.

I fixed this in the repository. It will be in the next version.
As a workaround create a path which does not contain spaces it (in the full path, that means not in your user subtree). Then set the environment variable TMP to this path and start then Hugin:

set TMP=c:\TempPathWithoutSpaces
hugin

This can also be packed in a bat file and then Hugin be started with the bat file.
Alternatively you can also change the environment variable TMP in the Control panel, section users. This will also affect other program which are using the temp folder.

So I’m just gonna wait for the next version of hugin rather than divert my TMP folder.

Thanks again for the help!