sharp
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High performance Node.js image processing, the fastest module to resize JPEG, PNG, WebP and TIFF images
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## toFile
Write output image data to a file.
If an explicit output format is not selected, it will be inferred from the extension,
with JPEG, PNG, WebP, TIFF, DZI, and libvips' V format supported.
Note that raw pixel data is only supported for buffer output.
By default all metadata will be removed, which includes EXIF-based orientation.
See [withMetadata][1] for control over this.
A `Promise` is returned when `callback` is not provided.
### Parameters
- `fileOut` **[String][2]** the path to write the image data to.
- `callback` **[Function][3]?** called on completion with two arguments `(err, info)`.
`info` contains the output image `format`, `size` (bytes), `width`, `height`,
`channels` and `premultiplied` (indicating if premultiplication was used).
When using a crop strategy also contains `cropOffsetLeft` and `cropOffsetTop`.
### Examples
```javascript
sharp(input)
.toFile('output.png', (err, info) => { ... });
```
```javascript
sharp(input)
.toFile('output.png')
.then(info => { ... })
.catch(err => { ... });
```
- Throws **[Error][4]** Invalid parameters
Returns **[Promise][5]<[Object][6]>** when no callback is provided
## toBuffer
Write output to a Buffer.
JPEG, PNG, WebP, TIFF and RAW output are supported.
If no explicit format is set, the output format will match the input image, except GIF and SVG input which become PNG output.
By default all metadata will be removed, which includes EXIF-based orientation.
See [withMetadata][1] for control over this.
`callback`, if present, gets three arguments `(err, data, info)` where:
- `err` is an error, if any.
- `data` is the output image data.
- `info` contains the output image `format`, `size` (bytes), `width`, `height`,
`channels` and `premultiplied` (indicating if premultiplication was used).
When using a crop strategy also contains `cropOffsetLeft` and `cropOffsetTop`.
A `Promise` is returned when `callback` is not provided.
### Parameters
- `options` **[Object][6]?**
- `options.resolveWithObject` **[Boolean][7]?** Resolve the Promise with an Object containing `data` and `info` properties instead of resolving only with `data`.
- `callback` **[Function][3]?**
### Examples
```javascript
sharp(input)
.toBuffer((err, data, info) => { ... });
```
```javascript
sharp(input)
.toBuffer()
.then(data => { ... })
.catch(err => { ... });
```
```javascript
sharp(input)
.toBuffer({ resolveWithObject: true })
.then(({ data, info }) => { ... })
.catch(err => { ... });
```
Returns **[Promise][5]<[Buffer][8]>** when no callback is provided
## withMetadata
Include all metadata (EXIF, XMP, IPTC) from the input image in the output image.
The default behaviour, when `withMetadata` is not used, is to strip all metadata and convert to the device-independent sRGB colour space.
This will also convert to and add a web-friendly sRGB ICC profile.
### Parameters
- `options` **[Object][6]?**
- `options.orientation` **[Number][9]?** value between 1 and 8, used to update the EXIF `Orientation` tag.
### Examples
```javascript
sharp('input.jpg')
.withMetadata()
.toFile('output-with-metadata.jpg')
.then(info => { ... });
```
- Throws **[Error][4]** Invalid parameters
Returns **Sharp**
## jpeg
Use these JPEG options for output image.
### Parameters
- `options` **[Object][6]?** output options
- `options.quality` **[Number][9]** quality, integer 1-100 (optional, default `80`)
- `options.progressive` **[Boolean][7]** use progressive (interlace) scan (optional, default `false`)
- `options.chromaSubsampling` **[String][2]** set to '4:4:4' to prevent chroma subsampling when quality <= 90 (optional, default `'4:2:0'`)
- `options.trellisQuantisation` **[Boolean][7]** apply trellis quantisation, requires libvips compiled with support for mozjpeg (optional, default `false`)
- `options.overshootDeringing` **[Boolean][7]** apply overshoot deringing, requires libvips compiled with support for mozjpeg (optional, default `false`)
- `options.optimiseScans` **[Boolean][7]** optimise progressive scans, forces progressive, requires libvips compiled with support for mozjpeg (optional, default `false`)
- `options.optimizeScans` **[Boolean][7]** alternative spelling of optimiseScans (optional, default `false`)
- `options.optimiseCoding` **[Boolean][7]** optimise Huffman coding tables (optional, default `true`)
- `options.optimizeCoding` **[Boolean][7]** alternative spelling of optimiseCoding (optional, default `true`)
- `options.quantisationTable` **[Number][9]** quantization table to use, integer 0-8, requires libvips compiled with support for mozjpeg (optional, default `0`)
- `options.quantizationTable` **[Number][9]** alternative spelling of quantisationTable (optional, default `0`)
- `options.force` **[Boolean][7]** force JPEG output, otherwise attempt to use input format (optional, default `true`)
### Examples
```javascript
// Convert any input to very high quality JPEG output
const data = await sharp(input)
.jpeg({
quality: 100,
chromaSubsampling: '4:4:4'
})
.toBuffer();
```
- Throws **[Error][4]** Invalid options
Returns **Sharp**
## png
Use these PNG options for output image.
PNG output is always full colour at 8 or 16 bits per pixel.
Indexed PNG input at 1, 2 or 4 bits per pixel is converted to 8 bits per pixel.
### Parameters
- `options` **[Object][6]?**
- `options.progressive` **[Boolean][7]** use progressive (interlace) scan (optional, default `false`)
- `options.compressionLevel` **[Number][9]** zlib compression level, 0-9 (optional, default `9`)
- `options.adaptiveFiltering` **[Boolean][7]** use adaptive row filtering (optional, default `false`)
- `options.palette` **[Boolean][7]** quantise to a palette-based image with alpha transparency support, requires libvips compiled with support for libimagequant (optional, default `false`)
- `options.quality` **[Number][9]** use the lowest number of colours needed to achieve given quality, requires libvips compiled with support for libimagequant (optional, default `100`)
- `options.colours` **[Number][9]** maximum number of palette entries, requires libvips compiled with support for libimagequant (optional, default `256`)
- `options.colors` **[Number][9]** alternative spelling of `options.colours`, requires libvips compiled with support for libimagequant (optional, default `256`)
- `options.dither` **[Number][9]** level of Floyd-Steinberg error diffusion, requires libvips compiled with support for libimagequant (optional, default `1.0`)
- `options.force` **[Boolean][7]** force PNG output, otherwise attempt to use input format (optional, default `true`)
### Examples
```javascript
// Convert any input to PNG output
const data = await sharp(input)
.png()
.toBuffer();
```
- Throws **[Error][4]** Invalid options
Returns **Sharp**
## webp
Use these WebP options for output image.
### Parameters
- `options` **[Object][6]?** output options
- `options.quality` **[Number][9]** quality, integer 1-100 (optional, default `80`)
- `options.alphaQuality` **[Number][9]** quality of alpha layer, integer 0-100 (optional, default `100`)
- `options.lossless` **[Boolean][7]** use lossless compression mode (optional, default `false`)
- `options.nearLossless` **[Boolean][7]** use near_lossless compression mode (optional, default `false`)
- `options.smartSubsample` **[Boolean][7]** use high quality chroma subsampling (optional, default `false`)
- `options.reductionEffort` **[Number][9]** level of CPU effort to reduce file size, integer 0-6 (optional, default `4`)
- `options.force` **[Boolean][7]** force WebP output, otherwise attempt to use input format (optional, default `true`)
### Examples
```javascript
// Convert any input to lossless WebP output
const data = await sharp(input)
.webp({ lossless: true })
.toBuffer();
```
- Throws **[Error][4]** Invalid options
Returns **Sharp**
## tiff
Use these TIFF options for output image.
### Parameters
- `options` **[Object][6]?** output options
- `options.quality` **[Number][9]** quality, integer 1-100 (optional, default `80`)
- `options.force` **[Boolean][7]** force TIFF output, otherwise attempt to use input format (optional, default `true`)
- `options.compression` **[Boolean][7]** compression options: lzw, deflate, jpeg, ccittfax4 (optional, default `'jpeg'`)
- `options.predictor` **[Boolean][7]** compression predictor options: none, horizontal, float (optional, default `'horizontal'`)
- `options.pyramid` **[Boolean][7]** write an image pyramid (optional, default `false`)
- `options.tile` **[Boolean][7]** write a tiled tiff (optional, default `false`)
- `options.tileWidth` **[Boolean][7]** horizontal tile size (optional, default `256`)
- `options.tileHeight` **[Boolean][7]** vertical tile size (optional, default `256`)
- `options.xres` **[Number][9]** horizontal resolution in pixels/mm (optional, default `1.0`)
- `options.yres` **[Number][9]** vertical resolution in pixels/mm (optional, default `1.0`)
- `options.squash` **[Boolean][7]** squash 8-bit images down to 1 bit (optional, default `false`)
### Examples
```javascript
// Convert SVG input to LZW-compressed, 1 bit per pixel TIFF output
sharp('input.svg')
.tiff({
compression: 'lzw',
squash: true
})
.toFile('1-bpp-output.tiff')
.then(info => { ... });
```
- Throws **[Error][4]** Invalid options
Returns **Sharp**
## heif
Use these HEIF options for output image.
Support for HEIF (HEIC/AVIF) is experimental.
Do not use this in production systems.
Requires a custom, globally-installed libvips compiled with support for libheif.
Most versions of libheif support only the patent-encumbered HEVC compression format.
### Parameters
- `options` **[Object][6]?** output options
- `options.quality` **[Number][9]** quality, integer 1-100 (optional, default `80`)
- `options.compression` **[Boolean][7]** compression format: hevc, avc, jpeg, av1 (optional, default `'hevc'`)
- `options.lossless` **[Boolean][7]** use lossless compression (optional, default `false`)
- Throws **[Error][4]** Invalid options
Returns **Sharp**
## raw
Force output to be raw, uncompressed uint8 pixel data.
### Examples
```javascript
// Extract raw RGB pixel data from JPEG input
const { data, info } = await sharp('input.jpg')
.raw()
.toBuffer({ resolveWithObject: true });
```
Returns **Sharp**
## toFormat
Force output to a given format.
### Parameters
- `format` **([String][2] \| [Object][6])** as a String or an Object with an 'id' attribute
- `options` **[Object][6]** output options
### Examples
```javascript
// Convert any input to PNG output
const data = await sharp(input)
.toFormat('png')
.toBuffer();
```
- Throws **[Error][4]** unsupported format or options
Returns **Sharp**
## tile
Use tile-based deep zoom (image pyramid) output.
Set the format and options for tile images via the `toFormat`, `jpeg`, `png` or `webp` functions.
Use a `.zip` or `.szi` file extension with `toFile` to write to a compressed archive file format.
Warning: multiple sharp instances concurrently producing tile output can expose a possible race condition in some versions of libgsf.
### Parameters
- `options` **[Object][6]?**
- `options.size` **[Number][9]** tile size in pixels, a value between 1 and 8192. (optional, default `256`)
- `options.overlap` **[Number][9]** tile overlap in pixels, a value between 0 and 8192. (optional, default `0`)
- `options.angle` **[Number][9]** tile angle of rotation, must be a multiple of 90. (optional, default `0`)
- `options.background` **([String][2] \| [Object][6])** background colour, parsed by the [color][10] module, defaults to white without transparency. (optional, default `{r:255,g:255,b:255,alpha:1}`)
- `options.depth` **[String][2]?** how deep to make the pyramid, possible values are `onepixel`, `onetile` or `one`, default based on layout.
- `options.skipBlanks` **[Number][9]** threshold to skip tile generation, a value 0 - 255 for 8-bit images or 0 - 65535 for 16-bit images (optional, default `-1`)
- `options.container` **[String][2]** tile container, with value `fs` (filesystem) or `zip` (compressed file). (optional, default `'fs'`)
- `options.layout` **[String][2]** filesystem layout, possible values are `dz`, `zoomify` or `google`. (optional, default `'dz'`)
### Examples
```javascript
sharp('input.tiff')
.png()
.tile({
size: 512
})
.toFile('output.dz', function(err, info) {
// output.dzi is the Deep Zoom XML definition
// output_files contains 512x512 tiles grouped by zoom level
});
```
- Throws **[Error][4]** Invalid parameters
Returns **Sharp**
[1]: #withmetadata
[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String
[3]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function
[4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error
[5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Promise
[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object
[7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
[8]: https://nodejs.org/api/buffer.html
[9]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number
[10]: https://www.npmjs.org/package/color