raw_demosaic_bilinear — GFX2D `isp` op

• Data kinds: image2d → rgb

• Call: import fullseye as fs; fs.ledger.raw_demosaic_bilinear(raw, pattern='RGGB') (to call the implementation directly, import gfx2d; gfx2d.raw_demosaic_bilinear(raw, pattern='RGGB'); from the registry, opsgfx2d.get("raw_demosaic_bilinear"))

Usage

Bayer mosaic → `(H, W, 3)` RGB by bilinear interpolation, in NumPy.

Red and blue occupy one pixel in four, so a missing value is the mean of

the measured neighbours (`[[1,2,1],[2,4,2],[1,2,1]]/4` on the masked

plane); green occupies two in four (`[[0,1,0],[1,4,1],[0,1,0]]/4`). The

border mirrors the mosaic two pixels out with a non-duplicating

reflection, which keeps the 2x2 phase, so a uniform field is exact up to the

edge. This is the same estimate the OpenCV bridge `cfa_to_rgb` makes with

`cv2.COLOR_Bayer*2RGB`, without the 8-bit round trip and without OpenCV.

Ground truth: three affine planes mosaicked and demosaicked come back to

1e-12 away from the border (a bilinear estimate of an affine field is the

field). Bilinear is the textbook baseline: it blurs colour edges into

zipper artefacts; edge-directed methods are not provided here.

Raises `ValueError`: bad *raw* or *pattern*.

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)

• raw_to_display_isp — py -3.11 examples/raw_to_display_isp.py

Ops the type connects to (they accept `rgb` as input)

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

Same category (`isp`)

raw_black_level · raw_dead_pixel_mask · raw_dead_pixel_correct · lens_shading_gain · lens_shading_correct · awb_gains · rgb_apply_gains · raw_apply_gains

*Provenance: gfx2d.py — GFX2D operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

raw_demosaic_bilinear — GFX2D isp op