Add experimental sharpness calc to stats #2251

docs/api-input.md

@@ -71,6 +71,7 @@ A `Promise` is returned when `callback` is not provided.
     -   `maxY` (y-coordinate of one of the pixel where the maximum lies)
 -   `isOpaque`: Is the image fully opaque? Will be `true` if the image has no alpha channel or if every pixel is fully opaque.
 -   `entropy`: Histogram-based estimation of greyscale entropy, discarding alpha channel if any (experimental)
+-   `sharpness`: Estimation of greyscale sharpness based on the standard deviation of a Laplacian convolution, discarding alpha channel if any (experimental)
 
 ### Parameters
 
@@ -87,6 +88,10 @@ image
   });
 ```
 
+```javascript
+const { entropy, sharpness } = await sharp(input).stats();
+```
+
 Returns **[Promise][5]<[Object][6]>** 
 
 [1]: https://libvips.github.io/libvips/API/current/VipsImage.html#VipsInterpretation

docs/changelog.md

@@ -21,6 +21,9 @@ Requires libvips v8.9.1
 * Add support for named `alpha` channel to `extractChannel` operation.
   [#2138](https://github.com/lovell/sharp/issues/2138)
 
+* Add experimental `sharpness` calculation to `stats()` response.
+  [#2251](https://github.com/lovell/sharp/issues/2251)
+
 ### v0.25.3 - 17th May 2020
 
 * Ensure libvips is initialised only once, improves worker thread safety.