fullseye

bloom — GFX2D post op

使い方

Bleed the bright parts of an image into their neighbourhood.

The classical three steps: isolate what is above threshold, blur it by a Gaussian of sigma, add intensity times the result back, clip.

A linear-light operator: light spreading in a lens adds radiance. Running it on sRGB-encoded values makes the halo too strong in the mid-tones — srgb_to_linear first, linear_to_srgb after.

Exact identities: intensity=0 and threshold >= 1 both return the input bit for bit, and a black image stays black.

The added energy is not conserved by the clip at the end. The suite measures both halves: on a centred bright blob the Gaussian preserves the bright mass to 5.0e-16 relative, so everything lost after that is the clip — on a random scene with a saturated square, 2.69 % of the pixels clip and 1.65 % of the total energy is thrown away, and neither number is returned to the caller.

参考(サンプルデータ・文献)

実行できる例(この op を実際に呼ぶ検証済みサンプル)

型が繋がる次の op(rgb を入力に取れる)

srgb_to_linear · linear_to_srgb · blend_mode · light_mask · normal_map_decode · vignette · chromatic_aberration · film_grain

同カテゴリ(post)

vignette · chromatic_aberration · film_grain · color_lut · color_grade · dither · palette_quantize


Provenance: gfx2d.py — GFX2D operator registry. この per-op ノートは tools/opdocs.py md が自動生成(手編集しない)。

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