Source Detection

The module provides tools and algorithms for detecting and extracting point-like sources.

Performance

Below are some benchmarks comparing the source detection capabilities of Photometry.jl with the photutils astropy package. The benchmark code can be found in the bench folder.

Julia Version 1.12.6
Commit 15346901f00 (2026-04-09 19:20 UTC)
Build Info:
  Official https://julialang.org release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 12 × AMD Ryzen 5 PRO 6650U with Radeon Graphics
  WORD_SIZE: 64
  LLVM: libLLVM-18.1.7 (ORCJIT, znver3)
  GC: Built with stock GC
Threads: 1 default, 1 interactive, 1 GC (on 12 virtual cores)

API/Reference

Photometry.Detection.extract_sources — Function

extract_sources(::SourceFinder, data, [error]; sorted=true)

Uses method to find and extract point-like sources.

Returns a TypedTables.Table with positions and information related to the method. For instance, using PeakMesh returns a table a column for the peak values.

data is assumed to be background-subtracted. If error is provided it will be propagated into the detection algorithm. If sorted is true the sources will be sorted by their amplitude.

error should be nothing or an AbstractArray defining the expected error in each pixel. If nothing is provided, any local maximum is returned, including negative values. The default is zeros(data), which means only positive pixels are returned.

See Also

Source Detection Algorithms

Example

julia> data = rand(2048, 2048);

julia> pm = PeakMesh((7, 7), 3.0)
PeakMesh
  box_size: Tuple{Int64, Int64}
  nsigma: Float64 3.0

julia> sources = extract_sources(pm, data)
Table with 3 columns and 86004 rows:
      x     y     value
    ┌─────────────────────
 1  │ 1120  1285  1.0
 2  │ 1751  845   1.0
 3  │ 1670  506   1.0
 4  │ 1792  666   1.0
 5  │ 314   1456  0.999999
 6  │ 1723  432   0.999999
 7  │ 209   322   0.999999
 8  │ 1872  334   0.999999
 9  │ 940   1269  0.999999
 10 │ 1624  493   0.999998
 11 │ 436   1202  0.999998
 12 │ 363   107   0.999998
 13 │ 1355  617   0.999998
 14 │ 1355  179   0.999998
 15 │ 1916  165   0.999997
 16 │ 931   1963  0.999997
 17 │ 1246  215   0.999996
 ⋮  │  ⋮     ⋮       ⋮

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