Documentation updated

README.md

@@ -3,6 +3,37 @@ Resize
 
 Image resizing for the [Go programming language](http://golang.org) that provides a few interpolation methods.
 
+Installation
+============
+
+```bash
+$ go get github.com/nfnt/resize
+```
+
+It's that easy!
+
+Usage
+=====
+
+Import package with
+
+```go
+import "github.com/nfnt/resize"
+```
+
+Resize creates a scaled image with new dimensions (w,h) using the interpolation function interp.
+
+```go
+resize.Resize(w int, h int, img image.Image, interp InterpolationFunction) image.Image 
+```
+
+The provided interpolation functions are
+
+- NearestNeighbor: Nearest-neighbor interpolation
+- Bilinear: Bilinear interpolation
+- Bicubic: Bicubic interpolation
+- Lanczos3: Convolution with windowed Sinc function, a=3
+
 License
 =======