Image.Plug.Pipeline.Ops.Crop (image_plug v0.1.0)

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Crop operation. Extracts a sub-rectangle of the working image.

Distinct from Image.Plug.Pipeline.Ops.Trim, which auto-detects or removes a border, and distinct from Image.Plug.Pipeline.Ops.Resize's fit modes, which scale-and-fit. Crop is an absolute extract of the region described by (x, y, width, height).

Two coordinate systems via :units:

  • :pixels (default) — x, y, width, height are measured in pixels of the source image. (0, 0) is the top-left corner.

  • :percent — all four values are floats in 0.0..100.0, interpreted as percentages of the source image's dimensions. The interpreter resolves them against the actual source size at apply time, which means the same op can be reused across sources of different dimensions.

Used by

  • The IIIF Image API 3.0 provider's region URL segment, which accepts both x,y,w,h (pixels) and pct:x,y,w,h (percent) forms.

Canonical order

Per Image.Plug.Pipeline.Normaliser, Crop runs after Trim / Background and before Resize. The IIIF spec processes operations in this same order — region → size → rotation → quality → format — so a IIIF round-trip preserves intent.

Summary

Types

t()
units()

Types

t()

@type t() :: %Image.Plug.Pipeline.Ops.Crop{
  height: number(),
  units: units(),
  width: number(),
  x: number(),
  y: number()
}

units()

@type units() :: :pixels | :percent