ImagePalette

from blanket import ImagePalette provides Pillow-compatible palette objects, including color allocation, copying, raw data, serialization, and the wedge, negative, random, and sepia factories. load reads text palettes, GIMP palettes, and GIMP RGB gradients. LUT generation, color indexing, palette ramps, sepia generation, and gradient rendering use the native Rust backend. Python preserves mutable palette storage and handles file parsing; random uses Python's random generator to match Pillow's seeded behavior.

from blanket import ImagePalette

palette = ImagePalette.ImagePalette("RGBA")
red_index = palette.getcolor((255, 0, 0, 128))
mode, data = palette.getdata()

Reference

ImagePalette

ImagePalette(mode: str = 'RGB', palette: Sequence[int] | bytes | bytearray | None = None)

An interleaved color palette, with RGB entries by default.

Configure ImagePalette.

Parameters:

Name	Type	Description	Default
mode	str	Palette channel layout, normally RGB or RGBA.	'RGB'
palette	Sequence[int] | bytes | bytearray | None	Interleaved channel values, or None for an empty palette.	None

Examples:

from blanket import ImagePalette

palette = ImagePalette.ImagePalette("RGB", [0, 0, 0, 255, 0, 0])

palette property writable

palette: Sequence[int] | bytes | bytearray

Mutable interleaved palette entries.

Examples:

from blanket import ImagePalette

palette = ImagePalette.wedge()
print(palette.palette)

colors property writable

colors: dict[tuple[int, ...], int]

Map channel tuples to their first palette index.

Examples:

from blanket import ImagePalette

palette = ImagePalette.wedge()
print(palette.colors)

copy

copy() -> ImagePalette

Copy the palette data and flags, rebuilding color lookup on demand.

Examples:

from blanket import ImagePalette

palette = ImagePalette.wedge()
result = palette.copy()

getdata

getdata() -> tuple[str, Sequence[int] | bytes | bytearray]

Return the raw mode and data, or the mode and serialized entries.

Examples:

from blanket import ImagePalette

palette = ImagePalette.wedge()
mode, entries = palette.getdata()

tobytes

tobytes() -> bytes

Serialize a non-raw palette to bytes.

Examples:

from blanket import ImagePalette

palette = ImagePalette.wedge()
entries = palette.tobytes()

getcolor

getcolor(color: tuple[int, ...], image: Image | _PaletteImage | None = None) -> int

Find or allocate a color, optionally reusing an unused image index.

Parameters:

Name	Type	Description	Default
color	tuple[int, ...]	RGB or RGBA tuple matching the palette mode.	required
image	Image | _PaletteImage | None	Optional indexed image whose unused entries may be reused.	None

Examples:

from blanket import ImagePalette

palette = ImagePalette.wedge()
palette = ImagePalette.ImagePalette("RGB")
index = palette.getcolor((255, 0, 0))

save

save(fp: str | IO[str]) -> None

Write a 256-entry text palette to a filename or text stream.

Parameters:

Name	Type	Description	Default
fp	str | IO[str]	Filename or writable text stream.	required

Examples:

from blanket import ImagePalette

palette = ImagePalette.wedge()
from io import StringIO

output = StringIO()
palette.save(output)

raw

raw(rawmode: str, data: Sequence[int] | bytes | bytearray) -> ImagePalette

Wrap encoded palette data without interpreting its layout.

Parameters:

Name	Type	Description	Default
rawmode	str	Channel layout of the palette data, normally RGB or RGBA.	required
data	Sequence[int] | bytes | bytearray	Raw encoded palette entries.	required

Examples:

from blanket import ImagePalette

result = ImagePalette.raw("RGB", bytes([0, 0, 0, 255, 0, 0]))

make_linear_lut

make_linear_lut(black: int, white: float) -> list[int]

Return a 256-entry linear intensity lookup table.

Parameters:

Name	Type	Description	Default
black	int	Black endpoint; only 0 is supported.	required
white	float	White endpoint of the linear ramp.	required

Examples:

from blanket import ImagePalette

result = ImagePalette.make_linear_lut(0, 255)

make_gamma_lut

make_gamma_lut(exp: float) -> list[int]

Return a 256-entry gamma correction lookup table.

Parameters:

Name	Type	Description	Default
exp	float	Gamma exponent applied to normalized intensity values.	required

Examples:

from blanket import ImagePalette

result = ImagePalette.make_gamma_lut(2.2)

negative

negative(mode: str = 'RGB') -> ImagePalette

Create a descending grayscale palette.

Parameters:

Name	Type	Description	Default
mode	str	Palette channel layout, normally RGB or RGBA.	'RGB'

Examples:

from blanket import ImagePalette

result = ImagePalette.negative()

random

random(mode: str = 'RGB') -> ImagePalette

Create a palette with 256 random colors.

Parameters:

Name	Type	Description	Default
mode	str	Palette channel layout, normally RGB or RGBA.	'RGB'

Examples:

from blanket import ImagePalette

result = ImagePalette.random()

sepia

sepia(white: str = '#fff0c0') -> ImagePalette

Create a black-to-sepia RGB palette.

Parameters:

Name	Type	Description	Default
white	str	CSS color for the lightest palette entry.	'#fff0c0'

Examples:

from blanket import ImagePalette

result = ImagePalette.sepia("#fff0c0")

wedge

wedge(mode: str = 'RGB') -> ImagePalette

Create an ascending grayscale palette.

Parameters:

Name	Type	Description	Default
mode	str	Palette channel layout, normally RGB or RGBA.	'RGB'

Examples:

from blanket import ImagePalette

result = ImagePalette.wedge()

load

load(filename: str) -> tuple[bytes, str]

Load a text palette, GIMP palette, or GIMP RGB gradient.

Parameters:

Name	Type	Description	Default
filename	str	Path to a text palette, GIMP palette, or GIMP gradient.	required

Examples:

from pathlib import Path
from tempfile import TemporaryDirectory
from blanket import ImagePalette

with TemporaryDirectory() as directory:
    path = str(Path(directory) / "palette.txt")
    ImagePalette.wedge().save(path)
    entries, mode = ImagePalette.load(path)