add Blur function to processor

pkg/processor/interface.go

@@ -10,6 +10,8 @@ type Processor interface {
 	Resize(image image.Image, width, height int) image.Image
 	// GrayScale takes an input byte array and returns the grayscaled byte array or error
 	GrayScale(image image.Image) image.Image
+	// Blur takes an input byte array and returns the blurred byte array or error
+	Blur(image image.Image) image.Image
 	// Watermark takes an input byte array, overlay byte array and opacity value
 	// and returns the watermarked image bytes or error
 	Watermark(base []byte, overlay []byte, opacity uint8) ([]byte, error)

pkg/processor/native/processor.go

@@ -7,6 +7,7 @@ import (
 	"image/draw"
 	"strings"
 
+	"github.com/anthonynsimon/bild/blur"
 	"github.com/anthonynsimon/bild/clone"
 	"github.com/anthonynsimon/bild/effect"
 	"github.com/anthonynsimon/bild/transform"
@@ -86,6 +87,11 @@ func (bp *BildProcessor) GrayScale(img image.Image) image.Image {
 	return effect.GrayscaleWithWeights(img, 0.299, 0.587, 0.114)
 }
 
+// Blur takes an input image and blur radius and returns the Gausian blurred image
+func (bp *BildProcessor) Blur(img image.Image, radius float64) image.Image {
+	return blur.Gaussian(img,radius)
+}
+
 // Flip takes an input image and returns the image flipped. The direction of flip
 // is determined by the specified mode - 'v' for a vertical flip, 'h' for a
 // horizontal flip and 'vh'(or 'hv') for both.