info

info reports what a file holds: its format, images, tables, traces, spectra, plate and experiment. It reads headers only, so it stays fast on multi-gigabyte files.

openreadout info [OPTIONS] [FILE]...

Flags

• --json: print the JSON wrapper instead of text.
• --view summary|full|structure|explain|format: what to show. Default summary.
  • full adds per-frame records, per-field provenance and the vendor’s metadata tree.
  • structure lists the container: images, planes, blocks, attachments and pyramid levels.
  • explain describes the file in plain words, with caveats and suggested next commands.
  • format only identifies the format from the file’s signature.
• --ask QUESTION: answer a question in plain words (“which channel is DAPI?”) from the experiment model. Implies --view explain.
• --max-images N: list at most N images (0 = all). Screening plates list their first 16 field images by default; images_total gives the count.

With --view full

• --no-vendor: leave out the vendor metadata tree.
• --no-provenance: leave out the provenance map.
• --all-frames: embed every per-frame record (default: the first 100 per image).
• --redact: replace values flagged as personal data with stable salted hashes. Needs --salt-file or OPENREADOUT_REDACT_SALT. See Personal data.
• --salt-file FILE: file holding the redaction salt.
• --sidecar[=DIR]: write each input’s full metadata to <file>.openreadout.json next to it, or under DIR mirroring the input paths, instead of printing it. An up-to-date sidecar is left alone.

Several inputs and tables

info takes the flags in Several inputs. With --tidy, --fields, --sample-sheet or -o it writes one metadata row per data set; see the batch table flags. For info, --fields takes index field names or all.

Examples

$ openreadout info mini.czi
mini.czi
  format: Zeiss CZI (czi) v1.0  size: 2.0 KiB  images: 1  planes: 1
  assurance: validated - …
  [0] -  8x8 z=1 c=1 t=1  uint8 XYCZT  px=0.1000 µm
      ch0 c0

Pick single values out of the JSON with the global --only flag:

openreadout info mini.czi --only /images/0/physical_size,/images/0/pixel_type

Explain a file, or ask about it:

openreadout info run.raw --view explain
openreadout info run.raw --ask "what was the gradient?"

Write metadata sidecars for a whole folder:

openreadout info --view full --sidecar -r --skip-unknown /data/2026-09-21

Notes

• Pyramidal and tiled images report resolution_levels: one entry per level, full resolution first, with sizes, downsample factors and tile sizes. Use --level and --region on stats, preview, export and check --planes to read them.
• A screening plate (Harmony, ImageXpress, CellVoyager, OME-Zarr HCS) is one data set whose images are its fields. plate.wells[].images lists the image indices of each well, and images[i].extra.well and field go the other way. See stats --per well for per-well numbers.
• How units, timestamps and the experiment model are normalized: Metadata.

JSON

• info, info --view full, info --view structure, info --view explain, info --view format
• --sidecar report and sidecar file
• Batch table and summary

Run openreadout info --help for the full help of your installed version.