BinaryFrontend gains a Threshold enum: Fixed(u8) (now tunable, was
hardcoded to 128) and Adaptive { window, t } — Bradley–Roth adaptive
thresholding computed via visioncortex's SummedAreaTable, O(pixels)
regardless of window size, for images with uneven lighting. Both use a
shared (r+g+b)/3 intensity so they agree on "dark"; the grayscale
checker_bw golden is unaffected.
Exposed through Config and all bindings: CLI (--threshold, --adaptive,
--adaptive-window, --adaptive-t), Python (constructor kwargs + getters/
setters), and the Node package (binaryThreshold, adaptive, adaptiveWindow,
adaptiveT). Adds tests covering fixed tunability and adaptive recovering
locally-dark marks under a brightness gradient that a global cutoff can't.
vtracer only decodes input, but image's default features pulled a full AV1
encoder (ravif/rav1e) and OpenEXR into the CLI binary and the Python wheel.
Restrict to decode-only input formats (png, jpeg, gif, bmp, webp, tiff, ico,
pnm, tga, qoi). The release binary drops from ~3.23 MB to ~2.46 MB and builds
faster; supported inputs are unchanged in practice (avif decode was never in
image's defaults anyway).
`vtracer in.png out.svg` now works alongside the `-i/--input` and
`-o/--output` flags. Input/output become optional positionals plus the
existing flags; an explicit flag wins over the positional, and a clear error
is shown if neither is given.
Chris Tsang