features

Inspect the capabilities of the installed Blanket build without Pillow or external Python dependencies.

from blanket import features

print(features.check("heif_decoder"))
print(features.version("jxl"))
features.blanketinfo()

Feature names

Names are case-sensitive. get_supported() lists available canonical names.

Name	Capability or version source
`blanket`	Installed Blanket version
`png`	PNG; Rust `png` crate version
`jpg` (`jpeg`)	JPEG; Rust `turbojpeg` wrapper version
`jxl` (`jpegxl`)	JPEG XL; linked libjxl version
`libtiff` (`tiff`)	TIFF; Rust `tiff` crate version
`webp`	WebP; linked libwebp version
`avif`	AVIF; Rust `ravif` encoder and `dav1d` decoder wrapper versions
`libheif`	Linked libheif version, independent of installed HEVC plugins
`heif` (`heic`)	HEIF/HEIC with both an HEVC decoder and encoder
`heif_decoder`, `heif_encoder`	Runtime HEVC plugin availability; linked libheif version
`bmp`, `ico`	BMP/ICO; Rust `image` crate version
`ppm` (`pgm`, `pbm`, `pnm`), `pam`, `tga`, `dds`, `qoi`	Extended raster formats; Rust `image` crate version; DDS reading only
`eps`	EPS reading; available when Ghostscript (`gs`) is on `PATH`; no backend version
`jpg_2000` (`jpeg2000`)	JPEG 2000; built-in OpenJPEG version
`gif`	GIF; Rust `gif` crate version
`pdf`	PDF writing; no separate backend version
`littlecms2`	LAB conversion; linked LittleCMS version
`libjpeg_turbo`	JPEG backend; Rust `turbojpeg` wrapper version

Rust crate versions are labeled with the crate name and recorded at build time. They do not report the versions of any native libraries wrapped by those crates. Native library versions come from the libraries linked to the extension.

Pillow-specific features pil, tkinter, freetype2, zlib, raqm, fribidi, harfbuzz, mozjpeg, zlib_ng, libimagequant, and xcb are recognized as unavailable. Blanket's PNG implementation uses Rust compression rather than the native zlib backend queried by Pillow.

Unknown names make check() warn and return False. version() returns None for unknown, unavailable, or unversioned features.

blanketinfo() prints the package, Python, platform, backend, and single-image format capabilities to stdout or a supplied text stream. Use supported_formats=False to omit the format list. PDF supports saving only; HEIF read/write availability is reported separately.

Reference

check

check(feature: str) -> bool

Check whether the installed build supports a feature.

Parameters:

Name	Type	Description	Default
`feature`	`str`	A feature name, such as `jpg`, `jxl`, or `heif`.	required

Returns:

Type	Description
`bool`	Whether the feature is available. HEIF requires both an HEVC decoder
`bool`	and encoder; query `heif_decoder` or `heif_encoder` separately
`bool`	for one direction. PDF availability means writing only. Unknown
`bool`	names emit `UserWarning` and return False.

Examples:

>>> from blanket import features
>>> features.check("png")
True

version

version(feature: str) -> str | None

Return the installed backend's version, if available.

Parameters:

Name	Type	Description	Default
`feature`	`str`	A name accepted by :func:`check`.	required

Returns:

Type	Description
`str \| None`	A native library version for JXL, WebP, libheif, or LittleCMS;
`str \| None`	a labeled Rust backend crate version for the other codecs; or
`str \| None`	None for unavailable, unknown, or unversioned features. JPEG reports
`str \| None`	the turbojpeg Rust wrapper, not the underlying libjpeg-turbo version.

Examples:

>>> from blanket import features
>>> features.version("blanket") is not None
True

get_supported

get_supported() -> list[str]

List the available canonical feature names.

Returns:

Type	Description
`list[str]`	Available feature names, without aliases.

Examples:

>>> from blanket import features
>>> "png" in features.get_supported()
True

blanketinfo

blanketinfo(out: TextIO | None = None, supported_formats: bool = True) -> None

Print build, backend, and format diagnostics.

Parameters:

Name	Type	Description	Default
`out`	`TextIO \| None`	Text stream to receive the report. Defaults to current stdout.	`None`
`supported_formats`	`bool`	Include format read/write capabilities.	`True`

Examples:

>>> from io import StringIO
>>> from blanket import features
>>> report = StringIO()
>>> features.blanketinfo(report, supported_formats=False)
>>> "Blanket" in report.getvalue()
True