View Source Image.Color (image v0.44.0)
Functions to manage image color and color conversion.
Summary
Types
Reference to an ICC color profile
An rbg color expressed as a list of numbers.
A color can be expressed as a list of numbers or as a CSS color name in atom or string format.
A transparency value which is one of the atoms :none,
:transparent or :opaque. Or an integer between 0 and
255 where 0 is transparent and 255 is opaque. Or a float
in the range 0.0 to 1.0 that is converted to the range
0 to 255.
Functions
Returns a mapping from CSS color names to CSS hex values and RGB triplets as a list.
Returns a mapping from CSS color names to CSS hex values and RGB triplets as a list - but only for greyscal colors.
Converts a hex color string to an RGB list.
Returns the list of color profiles built into
libvips.
Guards whether a given value can be interpreted as a color value.
Guards whether a given profile is one of the inbuilt profiles.
Returns a boolean indicating if the given profile is known and can be used for image operations.
Converts a color name or RGB value to a hex string.
Validates a color returning an
[r, g, b] triplet or error.
Returns a transparency value in the range 0 to 255 where 0 means transparent and 255 means opqque.
Types
@type icc_profile() :: :none | :cmyk | :srgb | :p3 | Path.t()
Reference to an ICC color profile
:nonemeans no profile:cmyk,:srgband:p3refer to the built-in color profilesPath.t()means any file system path. If the path is a relative path then is will be loaded from the systems profile directory.
An rbg color expressed as a list of numbers.
The number of list elements and the type varies depending on the image format, colorspace and dimensions.
For a common sRGB image it will be a list of
three of four images. If the fourth number is provided
it will be considered as an alpha transparency band.
A color can be expressed as a list of numbers or as a CSS color name in atom or string format.
@type transparency() :: :none | :transparent | :opaque | non_neg_integer() | float()
A transparency value which is one of the atoms :none,
:transparent or :opaque. Or an integer between 0 and
255 where 0 is transparent and 255 is opaque. Or a float
in the range 0.0 to 1.0 that is converted to the range
0 to 255.
Functions
Returns a mapping from CSS color names to CSS hex values and RGB triplets as a list.
Returns a mapping from CSS color names to CSS hex values and RGB triplets as a list - but only for greyscal colors.
Converts a hex color string to an RGB list.
Arguments
color is a hex string representing an RGB color. It has
the form #RRGGBB.
Returns
{:ok, [r, g, b]}or{:error, reason}.
Examples
iex> Image.Color.validate_color "#0000FF"
{:ok, [0, 0, 255]}Returns the list of color profiles built into
libvips.
Guards whether a given value can be interpreted as a color value.
Guards whether a given profile is one of the inbuilt profiles.
Returns a boolean indicating if the given profile is known and can be used for image operations.
Converts a color name or RGB value to a hex string.
Arguments
color which can be specified as a single integer
which or a list of integers representing the color.
The color can also be supplied as a CSS color name as a
string or atom. For example: :misty_rose. See
Image.Color.color_map/0 and Image.Color.rgb_color/1.
Returns
{:ok, #RRGGBB}string or{:error, reason}.
Examples
iex> Image.Color.rgb_to_hex(:green)
{:ok, "#008000"}
iex> Image.Color.rgb_to_hex([10,20,30])
{:ok, "#A141E"}Validates a color returning an
[r, g, b] triplet or error.
Arguments
color which can be specified as a single integer
which or a list of integers representing the color.
The color can also be supplied as a CSS color name as a
string or atom. For example: :misty_rose. See
Image.Color.color_map/0 and Image.Color.rgb_color/1.
Returns
{:ok, [r, g, b]}or{:error, reason}
Returns a transparency value in the range 0 to 255 where 0 means transparent and 255 means opqque.