doc: add I2K2025 sample data links

Author: bogovicj

README.md

@@ -9,4 +9,7 @@ JA Bogovic, P Hanslovsky, A Wong, S Saalfeld, "Robust registration of calcium im
 
 See the main [bigwarp page](http://fiji.sc/BigWarp) for details.
 
+## Resources
+
+* [I2K 2025 workshop sample data](doc/BigWarpI2K2025.md)
 * [I2K 2024 workshop instructions](doc/BigWarpI2K2024.md)

doc/BigWarpI2K2025.md

@@ -0,0 +1,22 @@
+# Manual image registration with BigWarp
+
+[Halfway to I2K 2025](https://www.i2kconference.org/workshops)
+Nov 18, 2025
+
+
+> BigWarp is an intuitive tool for non-linear manual image registration that can scale to terabyte-sized image data. In this
+> workshop, participants will learn to perform image registration with BigWarp, apply transformations to large images, import and
+> export transformations to and from other tools, and fine-tune the results of automatic registration algorithms. BigWarp makes
+> heavy use of the N5-API to store and load large image and transformation data and meta-data using the current NGFF formats HDF5,
+> Zarr, and N5. In addition to basic usage, the concepts, tips, and best practices discussed will extend to other registration
+> tools and help users achieve practical success for realistic and challenging data. Users will also get an introduction into an
+> excellent use case for OME-NGFF.
+
+
+## Sample data
+
+* The sample data are open organelle's [jrc_mus-kidney-3 data](https://openorganelle.janelia.org/datasets/jrc_mus-kidney-3)
+* Copies of the sample data are available for download:
+    * [medium (~1.4G)](https://figshare.com/s/408097a1651139088651)
+    * [small (~80M)](https://figshare.com/s/f7b2bdb6492678114fe4)
+