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WEBKNOSSOS can read N5 datasets.

N5 datasets can both be uploaded to WEBKNOSSOS through the web uploader or streamed from a remote server or the cloud.


You can try the N5 support with the following datasets. Load them in WEBKNOSSOS as a remote dataset:

  • Interphase HeLa cell EM data hosted on AWS S3

N5 folder structure

WEBKNOSSOS expects the following file structure for N5 datasets:

my_dataset.n5             # One root folder per dataset
├─ attributes.json        # Dataset metadata
└─ my_EM                  # One N5 group per data layer. In WK directly link to a N5 group.
   ├─ attributes.json                
   ├─ s0                  # Chunks in a directory hierarchy that enumerates their positive integer position in the chunk grid. (e.g. 0/4/1/7 for chunk grid position p=(0, 4, 1, 7)).
   │  ├─ 0
   │  │  ├─ <chunks>
   │  ├─ ...
   │  └─ n
   └─ sn                

For details see the N5 spec.

Performance Considerations

To get the best streaming performance for N5 datasets consider the following settings.

  • Use chunk sizes of 32 - 128 voxels^3