OPM Data processing in Fiji
OPM Data
The data generated by the OPM is in TIFF format. Whether you acquire a single image or a z-stack, you will get a single TIFF file containing all the images.
The software also saves an "experiment" file in Yaml format that contains all the experiment settings as well as a "waveform_constants" file in Yaml format that contains the waveform settings. These files can be opened by different applications such as notepad, etc. If you have Visual Studio on your computer, it is a great application to open the file in a structured way. See example below.
Data processing with Fiji/ImageJ
Of course, you are welcome to use any software/method you like to processprocess, analyze and render your data. The TIFF file format should make it easy to open by most sofwares.softwares.
However, until further development of the instrument, the acquired data is skewed due to the angle of the beam scanning to capture the z-stack. Before visualizing it, you will need to perform a shearing operation to "de-skew" the data.
ThisTHE sectionBECKMAN introducesCENTER STAFF WILL DO THIS FOR YOU!!
But if you are curious about how to do it yourself, here are the steps:
There is a way to do this using Fiji/ImageJ. It requires a GPU and CLIJ installed on ImageJ.
- How to install CLIJ on
ImageJ:ImageJ:- Follow the steps indicated on this github page. A Wiki page about CLIJ will be available soon as well.
- Shearing the
data:data:- Drag and drop the Fiji macros code in Fiji (
Fiji_GPU_sheared_batch_v3provided to you by Beckman Center staff). - Go in your experiment folder and copy the TIFF file of your z-stack into
aan empty separate folder (call it "Raw Data" to avoid confusion) - On the code, update the angle values if different than 40 degrees, and the z step size. The xy pixel size should not change for this microscope.
- Click Run and when prompted, select the TIFF file of your z-
stack.stack in the Raw Data folder.
- Drag and drop the Fiji macros code in Fiji (
SomeRotatetips toand visualize the data:ResliceTwofrommore scripts are used to visualize and rotate theLeftdata Z-projecttomaxtopintensityview Re-scaleand side view. They can be provided to you by the Beckman center staff.
Rotation
In practice, once your experiment is finished, the Beckman Center staff will give you the processed data. However, if you are an enthusiastic Fiji user and want to top-view:further process
and analyze you data in Fiji you might find it useful to be able to perform the de-skewing operations yourself to tweak them to your needs.