颜色操纵

background

Set the background for the embed, flatten and extend operations. The default background is {r: 0, g: 0, b: 0, alpha: 1}, black without transparency.

Delegates to the color module, which can throw an Error but is liberal in what it accepts, clipping values to sensible min/max. The alpha value is a float between 0 (transparent) and 1 (opaque).

参数

  • rgba (String | Object) parsed by the color module to extract values for red, green, blue and alpha.

  • Throws Error Invalid parameter

返回 Sharp

greyscale

Convert to 8-bit greyscale; 256 shades of grey. This is a linear operation. If the input image is in a non-linear colour space such as sRGB, use gamma() with greyscale() for the best results. By default the output image will be web-friendly sRGB and contain three (identical) color channels. This may be overridden by other sharp operations such as toColourspace('b-w'), which will produce an output image containing one color channel. An alpha channel may be present, and will be unchanged by the operation.

参数

  • greyscale Boolean (optional, default true)

返回 Sharp

grayscale

Alternative spelling of greyscale.

参数

  • grayscale Boolean (optional, default true)

返回 Sharp

toColourspace

Set the output colourspace. By default output image will be web-friendly sRGB, with additional channels interpreted as alpha channels.

参数

  • colourspace String? output colourspace e.g. srgb, rgb, cmyk, lab, b-w ...

  • Throws Error Invalid parameters

返回 Sharp

toColorspace

Alternative spelling of toColourspace.

参数

  • colorspace String? output colorspace.

  • Throws Error Invalid parameters

返回 Sharp