Re: How to align images manually and merge them into a multi-channel composite image?
You can create a composite image from your unaligned images, then
copy-paste one channel. After pasting, you can click and drag to whatever
arbitrary position you want. Make sure you activate Composite mode in
Channels Tool (Ctrl-Shift-Z) so you can see the other channels while you
move the active channel.
From: ImageJ Interest Group [[hidden email]] on behalf of Jiseok [[hidden email]]
Sent: Wednesday, May 23, 2018 20:52
To: [hidden email] Subject: Re: How to align images manually and merge them into a multi-channel composite image?
Thanks a lot, this was super helpful!
By the way, I can only move the channel image in X-Y direction, but I cannot
rotate it to align, right?
The one I recommended (align with line ROI) does translation, uniform scale, and rotation.
Most of the ones I saw suggested will offer a choice of possible transformations, usually including:
*translation and rotation
*translation, rotation, and uniform scaling
*and more...up to arbitrary rubber-sheet warping
I had a rather nice (but crude) version that allows you to manually specify 1, 2, or 3 landmark pairs, and
then selects the type of transformation based on your choice. I was about to make it bullet-proof, when
I discovered "align with line ROI", which does everything I need (short of automatic registration) at the moment.
The major problem I have in automatic registration is that my images tend to be multi-modal, meaning that the shapes and the
intensity values are radically different from image to image. Things like SIFT work great...until they don't.
Since I'm lazy, and I only write the code, and not use it - I'm not unhappy pushing the task off on the poor image reader.
My current guideline is that I will use auto methods if:
a) the imaging is fairly consistent, with the major difference being the position of the camera wrt the scene, or
b) there are more than 20 images in a given stack to be aligned (in these cases, I try to process away the
imaging differences so that the registration plugin can handle it.
Otherwise: my current standard is "align with line ROI". Most of my "customers" spend a long time examining
the images, so the extra time to locate 2 landmarks (in each image) is not onerous. Your milage may vary.
[hidden email] Vision is the art of seeing what is invisible to others.
Right, with the basic method I suggested you cannot manually rotate.
You'd have to copy the channel out to a different window with Image >
Duplicate (Ctrl-Shift-D), then rotate it (Image > Transform > Rotate)
and paste it back into the composite image. You'd have to do multiple
iterations of this duplicate-rotate-paste at different angles.