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Transloadit is the world’s most versatile file uploading & encoding service for web and mobile apps.

We launched in 2009 and our customers have been loving our clever API and top-notch customer support ever since.

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The /image/resize Robot

Transloadit can resize, crop, and (auto-)rotate images, as well as watermark them or read & write meta-data.

The /image/resize Robot resizes, crops, changes colorization, rotation, and applies text and watermarks to images.

The /image/resize Robot's Parameters

Name	Type	Default	Description
`width`	Integer(`1`-`5000`)	Auto	Width of the new image, in pixels. If not specified, will default to the width of the input image
`height`	Integer(`1`-`5000`)	Auto	Height of the new image, in pixels. If not specified, will default to the height of the input image
`strip`	Boolean	`false`	Strips all metadata from the image. This is useful to keep thumbnails as small as possible.
`flatten`	Boolean	`true`	Flattens all layers onto the specified background to achieve better results from transparent formats to non-transparent formats, as explained in the ImageMagick documentation. Note To preserve animations, GIF files are not flattened when this is set to `true`. To flatten GIF animations, use the `frame` parameter.
`correct_gamma`	Boolean	`false`	Prevents gamma errors common in many image scaling algorithms.
`quality`	Integer(`1`-`100`)	Quality	Controls the image compression for JPG and PNG images. Please also take a look at our /image/optimize Robot. Before: Quality `40` applied: If this parameter is not specified it will default to the quality of the input image, or `92`
`background`	String	`"#FFFFFF"`	Either the hexadecimal code or name of the color used to fill the background (only used for the pad resize strategy). Note By default, the background of transparent images is changed to white. For details about how to preserve transparency across all image types, see this demo.
`resize_strategy`	String	`"fit"`	See the list of available resize strategies.
`zoom`	Boolean	`true`	If this is set to `false`, smaller images will not be stretched to the desired width and height. For details about the impact of zooming for your preferred resize strategy, see the list of available resize strategies.
`crop`	Object / JSON String	`null`	Specify an object containing coordinates for the top left and bottom right corners of the rectangle to be cropped from the original image(s). For example, `{x1: 80, y1: 100, x2: 160, y2: 180}` will crop the area from `(80, 100)` to `(160, 180)` which is a square whose width and height are 80px. If `crop` is set, the width and height parameters are ignored, and the `resize_strategy` is set to `crop` automatically. You can also use a JSON string of such an object with coordinates in similar fashion: `"{ \"x1\": <Integer>, \"y1\": <Integer>, \"x2\": <Integer>, \"y2\": <Integer> }"`
`format`	String	Auto	Some of the most important available formats are `"jpg"`, `"png"`, `"gif"`, `"tiff"` and `"pdf"`. For a complete lists of all formats that we can write to please check our supported image formats list. If this parameter is not specified it will default to the format of the input image
`gravity`	String	`center`	The direction from which the image is to be cropped. The available options are `"center"`, `"top"`, `"bottom"`, `"left"`, and `"right"`. You can also combine options with a hyphen, such as `"bottom-right"`.
`frame`	Integer / Null	`null`	Use this parameter when dealing with animated GIF files to specify which frame of the GIF is used for the operation. Specify `1` to use the first frame, `2` to use the second, and so on. `null` means all frames.
`colorspace`	String	`""`	Sets the image colorspace. For details about the available values, see the ImageMagick documentation. Please note that if you were using `"RGB"`, we recommend using `"sRGB"` instead as of 2014-02-04. ImageMagick might try to find the most efficient `colorspace` based on the color of an image, and default to e.g. `"Gray"`. To force colors, you might then have to use this parameter in combination with `type` `"TrueColor"`
`type`	String	`""`	Sets the image color type. For details about the available values, see the ImageMagick documentation. If you're using `colorspace`, ImageMagick might try to find the most efficient based on the color of an image, and default to e.g. `"Gray"`. To force colors, you could e.g. set this parameter to `"TrueColor"`
`sepia`	Integer(`0`-`99`) / Null	`null`	Sets the sepia tone in percent. Before:
`rotation`	String / Boolean / Integer	`true`	Determines whether the image should be rotated. Set this to `true` to auto-rotate images that are rotated in a wrong way, or depend on EXIF rotation settings. You can also set this to an integer to specify the rotation in degrees. You can also specify `"degrees"` to rotate only when the image width exceeds the height (or `"degrees"` if the width must be less than the height). Specify `false` to disable auto-fixing of images that are rotated in a wrong way.
`compress`	String / Null	`null`	Specifies pixel compression for when the image is written. Valid values are `"None"`, `"BZip"`, `"Fax"`, `"Group4"`, `"JPEG"`, `"JPEG2000"`, `"Lossless"`, `"LZW"`, `"RLE"`, and `"Zip"`. Compression is disabled by default. Please also take a look at our /image/optimize Robot.
`blur`	String / Null	`null`	Specifies gaussian blur, using a value with the form `{radius}x{sigma}`. The radius value specifies the size of area the operator should look at when spreading pixels, and should typically be either `"0"` or at least two times the sigma value. The sigma value is an approximation of how many pixels the image is "spread"; think of it as the size of the brush used to blur the image. This number is a floating point value, enabling small values like `"0.5"` to be used.
`progressive`	Boolean	`false`	Interlaces the image if set to `true`, which makes the image load progressively in browsers. Instead of rendering the image from top to bottom, the browser will first show a low-res blurry version of the images which is then quickly replaced with the actual image as the data arrives. This greatly increases the user experience, but comes at a cost of a file size increase by around 10%.
`transparent`	String	`""`	Make this color transparent within the image.
`trim_whitespace`	Boolean	`false`	This determines if additional whitespace around the image should first be trimmed away. If you set this to `true` this parameter removes any edges that are exactly the same color as the corner pixels.
`clip`	Boolean / String	`false`	Apply the clipping path to other operations in the resize job, if one is present. If set to `true`, it will automatically take the first clipping path. If set to a String it finds a clipping path by that name.
`negate`	Boolean	`false`	Replace each pixel with its complementary color, effectively negating the image. Especially useful when testing clipping.
`density`	String	`null`	While in-memory quality and file format depth specifies the color resolution, the density of an image is the spatial (space) resolution of the image. That is the density (in pixels per inch) of an image and defines how far apart (or how big) the individual pixels are. It defines the size of the image in real world terms when displayed on devices or printed. You can set this value to a specific `width` or in the format `width`x`height`. If your converted image has a low resolution, please try using the density parameter to resolve that.

See full docs