mirror of
https://github.com/lovell/sharp.git
synced 2025-07-10 02:50:15 +02:00
137 lines
3.3 KiB
Markdown
137 lines
3.3 KiB
Markdown
<!-- Generated by documentation.js. Update this documentation by updating the source code. -->
|
|
|
|
### Table of Contents
|
|
|
|
- [background][1]
|
|
- [Parameters][2]
|
|
- [tint][3]
|
|
- [Parameters][4]
|
|
- [greyscale][5]
|
|
- [Parameters][6]
|
|
- [grayscale][7]
|
|
- [Parameters][8]
|
|
- [toColourspace][9]
|
|
- [Parameters][10]
|
|
- [toColorspace][11]
|
|
- [Parameters][12]
|
|
|
|
## 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).
|
|
|
|
### Parameters
|
|
|
|
- `rgba` **([String][13] \| [Object][14])** parsed by the [color][15] module to extract values for red, green, blue and alpha.
|
|
|
|
|
|
- Throws **[Error][16]** Invalid parameter
|
|
|
|
Returns **Sharp**
|
|
|
|
## tint
|
|
|
|
Tint the image using the provided chroma while preserving the image luminance.
|
|
An alpha channel may be present and will be unchanged by the operation.
|
|
|
|
### Parameters
|
|
|
|
- `rgb` **([String][13] \| [Object][14])** parsed by the [color][15] module to extract chroma values.
|
|
|
|
|
|
- Throws **[Error][16]** Invalid parameter
|
|
|
|
Returns **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.
|
|
|
|
### Parameters
|
|
|
|
- `greyscale` **[Boolean][17]** (optional, default `true`)
|
|
|
|
Returns **Sharp**
|
|
|
|
## grayscale
|
|
|
|
Alternative spelling of `greyscale`.
|
|
|
|
### Parameters
|
|
|
|
- `grayscale` **[Boolean][17]** (optional, default `true`)
|
|
|
|
Returns **Sharp**
|
|
|
|
## toColourspace
|
|
|
|
Set the output colourspace.
|
|
By default output image will be web-friendly sRGB, with additional channels interpreted as alpha channels.
|
|
|
|
### Parameters
|
|
|
|
- `colourspace` **[String][13]?** output colourspace e.g. `srgb`, `rgb`, `cmyk`, `lab`, `b-w` [...][18]
|
|
|
|
|
|
- Throws **[Error][16]** Invalid parameters
|
|
|
|
Returns **Sharp**
|
|
|
|
## toColorspace
|
|
|
|
Alternative spelling of `toColourspace`.
|
|
|
|
### Parameters
|
|
|
|
- `colorspace` **[String][13]?** output colorspace.
|
|
|
|
|
|
- Throws **[Error][16]** Invalid parameters
|
|
|
|
Returns **Sharp**
|
|
|
|
[1]: #background
|
|
|
|
[2]: #parameters
|
|
|
|
[3]: #tint
|
|
|
|
[4]: #parameters-1
|
|
|
|
[5]: #greyscale
|
|
|
|
[6]: #parameters-2
|
|
|
|
[7]: #grayscale
|
|
|
|
[8]: #parameters-3
|
|
|
|
[9]: #tocolourspace
|
|
|
|
[10]: #parameters-4
|
|
|
|
[11]: #tocolorspace
|
|
|
|
[12]: #parameters-5
|
|
|
|
[13]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
|
|
|
|
[14]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
|
|
|
|
[15]: https://www.npmjs.org/package/color
|
|
|
|
[16]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error
|
|
|
|
[17]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
|
|
|
|
[18]: https://github.com/jcupitt/libvips/blob/master/libvips/iofuncs/enumtypes.c#L568
|