Create transform images

[rijobro]

Partly addresses #2721.

Description

Automatic generation of transform example image and add to the docstring.

Status

Ready

Types of changes

• Non-breaking change (fix or new feature that would not break existing functionality).

[wyli]

looks great! the only concern is the image files, could we host the images elsewhere, so that we keep the primary codebase small?

[rijobro]

Could do but it would mean that we can't automate it (easily) as we can this way. Current images are 250kB, if we have 100 transforms to visualise that's 25MB. Is that too much? We could downsample by factor 2 to reduce to 6MB, and I'm sure we could play with data types to further reduce. What do you think?

[wyli]

I think every time we modify the images it'll create another copy in the git history and increase the size of the .git folder, this might not scale...

[ericspod]

I think it's best we store this data elsewhere, we've used gdrive and other sources before, we can do that for now at least.

[rijobro]

Do we have an official MONAI gdrive (or similar)? I wouldn't want to have it on my personal and then accidentally delete it.

[wyli]

Do we have an official MONAI gdrive (or similar)? I wouldn't want to have it on my personal and then accidentally delete it.

Thanks, I was looking for some other options but couldn't get an idea. Creating a new GitHub repo as you did looks good to me. Further in this direction, perhaps we need a way to dynamically inject the URLs with a global variable? https://stackoverflow.com/questions/57417808/standardizing-a-link-using-a-global-variable-in-sphinx-documentation

[rijobro]

Hi @ericspod @wyli
I created a new repository and will store the images there. I won't use it as a git submodule as these can get messy. Instead I'll use an environment variable pointing to that repository. Using git is advantageous in that (a) we can all add to it and (b) the URLs that get created are consistent (unlike gdrive that contains some random characters).

[ericspod]

Another repository makes sense. We should keep an eye on how large its .git directory gets over time to see if it's really an issue, Github's LFS is a thing as well that's meant to help manage large files and prevent that kind of issue. We keep talking about it and never trying it.

[rijobro]

I used git LFS for another test base and although it's fine, I think it might be overkill for this use case.

Would someone be able to review, and when happy, update the branch and enable auto-merge?

[wyli]

I hope there's some sphinx plugin to handle the URLs, something like https://github.com/Project-MONAI/DocImages/raw/[version]/transforms/RandFlip.png where [version] could be the tag from the main repo such as main, 0.7.0, 1.0 so that each code release has the corresponding version of images... or is this functionality just too much for now for the transforms?

[wyli]

@SachidanandAlle mentioned that providing this utility to the users so that they can visualise the effects of the transforms for any input images. Looks like a nice feature to have cc @rijobro @Nic-Ma @ericspod