Parameter reference
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Every parameter the Image API accepts, with the values it recognises. Parameters are applied in the order they are given, except that images are turned the right way up first and format and quality are applied last.
| Parameter | Short | Values | Notes |
|---|---|---|---|
width | w | Whole number of pixels | Given on its own, the height follows the aspect ratio. Keep it next to height. |
height | h | Whole number of pixels | Given on its own, the width follows the aspect ratio. |
fit | max, contain, fill, stretch, crop, crop-top (crop-t), crop-bottom (crop-b), crop-left (crop-l), crop-right (crop-r) | Default max. Must follow the width and height. An unrecognised value falls back to max. | |
crop | width,height,anchor or width,height,x,y | Anchors: center (c), top (t), bottom (b), left (l), right (r), top-left (tl), top-right (tr), bottom-left (bl), bottom-right (br). | |
fp | x,y between 0 and 1 | The point a crop is composed around. Give it after the dimensions and fit. Send the comma literally. | |
background | bg | Hex colour of 3, 4, 6 or 8 digits | Fills transparency that exists when it is reached, so give it after the fit or rotation. |
rotate | r | 1 to 359 | Clockwise. Angles other than 90, 180 and 270 leave empty corners. |
flip | horizontal (h), vertical (v), both (b) | ||
blur | b | 1 to 100 | Measured in pixels, so resize before blurring for a consistent result. |
effect | e | grayscale | American spelling only. |
format | f | jpeg, png, webp, gif, tiff, bmp | Applied last. An unrecognised value returns a JPEG. bmp returns a PNG. Without it the original format is kept, except a TIFF which is returned as WebP. |
quality | q | 1 to 100 | Applied last. JPEG and WebP only, defaulting to 75 and 80. Ignored for PNG, GIF and TIFF. |
invalidationKey | Any value | Allows an image requested by its plain path to be cached for a year. Change it whenever the image changes. |
Limits
- A transformed image is at most 16 megapixels, and no more than 8,192 pixels on its longest side. Larger requests are scaled down to fit.
- A source image is not transformed above 50MB, or if its frame is larger than 50 megapixels. Neither limit applies to a request with no transformation parameters, which returns the original.
- A parameter or value the Image API does not recognise is ignored, and the rest of the request still applies.