MPO

[cmahnke]

This isn't a real feature request, just an idea (since the discussion tab isn't enabled):
Consider adding MPO support, since some digital 3D cameras produce this format natively.

[2sh]

Saving as MPO was something I was looking into before, but I remember I found other people's work and didn't want to just copy it, and the format itself I had trouble understanding at the time. I'll look into it again now though as it's a feature I'd like this to have.

[cmahnke]

Well, I used it simply by importing Pillow, no need to duplicate other peoples work.
From my point of view it's just a question if there is a use case - I don't need it anymore...

[2sh]

Oh I only just clicked on your MPO link. I didn't realise Pillow can write them now, nice. I'll add it when I have some time. My use case was viewing stereoscopic images on my 3DS, it takes MPO files.

[cmahnke]

That's actually a great idea, hopefully I get my hands on a cheap 3DS in the future...

[2sh]

I got my 3DS out again, and I've created MPO files for it from Python. They work, but I remembered again why I had trouble with this format.
The Nintendo 3DS Camera app software has two extra features, a slider for zooming the image and a slider for "focusing" / shifting the two images for alignment. These features are only available when viewing MPO files with specific metadata/EXIF data, the metadata added by the 3DS camera for example.
I've tried copying the metadata from an MPO image taken from the camera with exiftool, I've tried setting the metadata with piexif in Python, but no luck so far.
With StereoscoPy's ability to align and crop the images, it's not too much of an issue really, but it would be a nice to have.

[cmahnke]

What I coincidence: I'm currently, struggling with adding metadata to a format similar to MPO using Python Pillow. Not Exif, but XMP...
The problem was adding metadata to the second image...