SplatTools.Inspect (SplatTools v0.1.0)

Identifies a Gaussian-splat PLY without decoding it.

This is the admission gate. A splat capture is 62 float32 per vertex — 248 bytes each — so a gigabyte file holds roughly 4.2 million rows and 260 million values. Handing one to a converter that then rejects it costs minutes of CPU and gigabytes of memory; reading the header costs a few kilobytes.

Everything here works from the PLY header alone.

Summary

Types

kind()

What a file turned out to be.

t()

Functions

require_splat(source)

Asserts that a source really is a splat, for callers that go on to convert it.

run(source)

Inspects a PLY and reports what it is.

run!(source)

Same as run/1, raising on error.

splat?(source)

Whether a file is a Gaussian-splat point cloud.

Types

kind()

@type kind() :: :splat | :mesh | :point_cloud

What a file turned out to be.

:splat — a Gaussian-splat point cloud
:mesh — an ordinary PLY with faces
:point_cloud — vertices with no splat properties and no faces

t()

@type t() :: %{
  kind: kind(),
  splat_count: non_neg_integer(),
  sh_bands: 0..3,
  sh_coefficients: non_neg_integer(),
  bytes_per_splat: pos_integer() | :variable,
  format: Ply.Header.format(),
  properties: [String.t()],
  has_normals: boolean()
}

Functions

require_splat(source)

@spec require_splat(Ply.source()) :: {:ok, t()} | {:error, SplatTools.Error.t()}

Asserts that a source really is a splat, for callers that go on to convert it.

Conversion is minutes of CPU and gigabytes of memory, so it is worth spending a few kilobytes to find out first.

run(source)

@spec run(Ply.source()) :: {:ok, t()} | {:error, SplatTools.Error.t()}

Inspects a PLY and reports what it is.

Accepts anything Ply.info/1 accepts — a path, or {:binary, contents}.

{:ok, info} = SplatTools.Inspect.run("capture.ply")
info.kind         #=> :splat
info.splat_count  #=> 1_284_331
info.sh_bands     #=> 3

run!(source)

@spec run!(Ply.source()) :: t()

Same as run/1, raising on error.

splat?(source)

@spec splat?(Ply.source()) :: boolean()

Whether a file is a Gaussian-splat point cloud.

A convenience over run/1 for callers that only need a yes or no; an unreadable file answers false rather than raising.