compressed_size — IMGMETRICS compression op

• Data kinds: image2d → scalar

• Call: import fullseye as fs; fs.ledger.compressed_size(a, compressor='lzma') (to call the implementation directly, import imgmetrics; imgmetrics.compressed_size(a, compressor='lzma'); from the registry, opsimgmetrics.get("compressed_size"))

Usage

Size in bytes of the array after lossless compression. The raw material for ncd.

Image codecs are not used -- putting one in between would measure that implementation's quirks. Only stdlib zlib / lzma. Differences in dtype and shape change the result, so the 2 images being compared must have the same dtype and the same shape.

Detailed usage guide

• image_difference_metrics family guide

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• image_quality_metrics — py -3.11 examples/image_quality_metrics.py

Ops the type connects to (they accept scalar as input)

luma_limited_u8 · rank_data · tid2013_index

Same category (compression)

ncd


*Provenance: imgmetrics.py — IMGMETRICS operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.