This library installs the prev_gen command-line tool to expose commonly used functions in a simpler format.
It can be used for previews and conversions between all supported formats, run it with no arguments for more details.
Each entry below is a class you can import from this library
(except the palette, that entry is needed to explain the usage modes)
- the user writes Preview(palette) instead of Preview(Palette(palette))
Usage 1 - "It just works"
(1d list) place colors in the order you want them to appear in the generated image
the program will figure out a rectangle big enough to fit them all
Usage 2 - "Do what I say"
(2d list) each inner list will be treated as a single row of colors, left-to-right
use this for full control over the placement of colors in the final image
- you can leave entire rows transparent if you pass an empty list
Check the example for a more direct explanation, it uses mode two.
Use Color('0000') to leave a spot empty - it's simply a fully transparent color
Available parameters
color: Color | str | Sequence[float] | NDArray
# The color value to assign, you need to include this value
# Or a hex string
# '#00f8' - blue with half opacity
# '#FFF' - white, letters can be capital too
# '00fa00' - off-green with full opacity
# '0000' - black with full transparency, equivalent to no color at all
# well, any fully transparent color works the same
# this is the way to leave a field empty in 3.0
# Or a css literal
name: str | None = None
# The name to display, hex if empty
desc_left: str | None = None
# Left corner description
desc_right: str | None = None
# Right corner description
model = 'srgb'Full list of models on github.
You can change the mode by specifying the type of color you want
Color((0.4, 0.2, 0.7)) # sRGB is the default
Color((0.4, 0.2, 0.7), model='oklch') # oklch is the suggested mode due to being based on human perception
Color((0.4, 0.2, 0.7), alpha=.5) # all work with transparencyyou can also specify a name for a color or not
Color((200, 100, 235), 'purple') # denormalized RGB with name
Color((0.2, 0.4, 0.7), model='hsv') # normalized HSV without nameHEX and CSS works regardless of mode specified
Color('#52C7A7', 'mint', model='hsv') # HEX with name (mode ignored)
Color('darkred', model='hsv') # CSS with no name (mode ignored)
# for css, name not added by default to allow for palettes without any namesBut not stopping you
This class actually converts the palette into a standard representation and generates meta information
This is also an iterator of the colors so you might find some use there
I don't expect this to actually be useful to anyone, but you can check the code out if you want
Available parameters
colors: list[Settings | Color] | list[Settings | list[Color]]
# The color palette used
# The long type hint is because of the two Usage modesIterator usage
palette = ...
t = Table(palette)
t.settings # Settings()
for i in t:
i.pos # top-left (x, y)
i.size # (x, y)
i.col # Color()- if you don't want to overwrite any settings just omit it
Available parameters
fileName: str = 'result'
# File name to save into (no extension, png)
fontName: str = 'Nunito'
# for png = local file name (no extension, true type)
# for svg = Google Font name
# the default is packaged with the module, no need to have installed
fontOpts: dict | None = None
# Google Fonts API options (for svg)
gridHeight: int = 168
# Height of each individual color tile
gridWidth: int = 224
# Width of each individual color tile
barHeight: int = 10
# Height of the darkened bar at the bottom of each tile
nameOffset: int = -10
# Vertical offset of the color name printed within the tile
hexOffset: int = 35
# Vertical offset of the hex value printed below color name
hexOffsetNameless: int = 0
# Vertical offset of the hex value printed if no name given
descOffsetX: int = 15
# Horizontal offset of the corner descriptions
descOffsetY: int = 20
# Vertical offset of the corner descriptions
nameSize: int = 40
# Text size of the color name
hexSize: int = 26
# Text size of the hex value printed under the color name
hexSizeNameless: int = 34
# Text size of the hex value printed if no name given
descSize: int = 26
# Text size of the corner descriptions
showHash: bool = False
# Display the hash symbol before hex colorsIt always returns the generated image, either as PIL.Image (png) or XML.etree.ElementTree (svg)
Available parameters
palette: list[Settings | Color] | list[Settings | list[Color]]
# The palette of colors to generate an image for
# The long type hint is because of the two Usage modes
show: bool = True
# Whether to display the generated image to the user
save: bool = False
# Whether to save the image to disk
output: Literal['png', 'svg'] = 'png'
# Output file typeTake an image and get back the code used to generate it
Available parameters
image: Image | ElementTree | str
save: Literal['py', 'yml', 'json', 'toml'] | None = None
# If set, will save the file to reverse.<ext>The internal configuration is a Python dictionary, but it can be saved in any of these formats with the use of the corresponding class
Available parameters
palette: list[Settings | list[Color]]
# the Usage 2 representation of the palette
output: Literal['py', 'yml', 'toml', 'json'] = 'yml'
# File Available attributes
palette -> internal usage2 representation
data -> formatted string
Available methods
.read(file) -> read a file into the internal representation
.write(filename) -> save to a formatted file
Available parameters
image: str | PIL.Image
# the filename to open or PIL.Image to useAvailable methods
iterate() -> Iterable[tuple[int, int]]
# iterate through (x, y) pixel coordinates with a progress bar
monochrome(chroma: float = 0., hue: float = 0., fileName: str | None = None) -> PIL.Image
# make a picture perceptually monochroma, with optional chroma and hue
# impossible colors get clipped to sRGBIf you change the example, it will be saved to gui.py.
It also returns the image, just in case you wanted it.
I don't expect people to use it, but if you only have a notepad - this at least has syntax highlighting.