blurhash.Encode() now requires image.Image instead of *image.Image (f…

…ixes #3)

It makes no sense to require a pointer to an interface type here,
as we don't make any special use of it.

.travis.yml

@@ -1,8 +1,8 @@
 language: go
 
 go:
-  - 1.11.x
-  - 1.12.x
+  - 1.13.x
+  - 1.14.x
 
 install:
   - go get -t -v ./...

README.md

@@ -33,7 +33,7 @@ BlurHash is written by [Dag Ågren](https://github.com/DagAgren) / [Wolt](https:
 
 go-blurhash exports three functions:
 ```go
-func blurhash.Encode(xComponents, yComponents int, rgba *image.Image) (string, error)
+func blurhash.Encode(xComponents, yComponents int, rgba image.Image) (string, error)
 func blurhash.Decode(hash string, width, height, punch int) (image.Image, error)
 func blurhash.Components(hash string) (xComponents, yComponents int, err error)
 ```
@@ -54,7 +54,7 @@ func main() {
 	// Generate the BlurHash for a given image
 	imageFile, _ := os.Open("test.png")
 	loadedImage, err := png.Decode(imageFile)
-	str, _ := blurhash.Encode(4, 3, &loadedImage)
+	str, _ := blurhash.Encode(4, 3, loadedImage)
 	if err != nil {
 		// Handle errors
 	}
@@ -88,6 +88,7 @@ func main() {
 - As mentioned [here](https://github.com/woltapp/blurhash#how-fast-is-encoding-decoding), it’s best to
 generate very small images (~32x32px) via BlurHash and scale them up to the desired dimensions afterwards for optimal performance.
 - Since [#2](https://github.com/buckket/go-blurhash/pull/2) we diverted from the reference implementation by memorizing sRGBtoLinear values, thus increasing encoding speed at the cost of higher memory usage.
+- Starting with v1.1.0 the signature of blurhash.Encode() has changed slightly (see [#3](https://github.com/buckket/go-blurhash/issues/3)).
 
 ## License
 

encode.go

@@ -41,7 +41,7 @@ func (e EncodingError) Error() string {
 // Encode calculates the Blurhash for an image using the given x and y component counts.
 // The x and y components have to be between 1 and 9 respectively.
 // The image must be of image.Image type.
-func Encode(xComponents int, yComponents int, rgba *image.Image) (string, error) {
+func Encode(xComponents int, yComponents int, rgba image.Image) (string, error) {
 	if xComponents < 1 || xComponents > 9 {
 		return "", InvalidParameterError{xComponents, "x"}
 	}
@@ -106,9 +106,9 @@ func Encode(xComponents int, yComponents int, rgba *image.Image) (string, error)
 	return blurhash.String(), nil
 }
 
-func multiplyBasisFunction(rgba *image.Image, factors []float64, xComponents int, yComponents int) {
-	height := (*rgba).Bounds().Max.Y
-	width := (*rgba).Bounds().Max.X
+func multiplyBasisFunction(rgba image.Image, factors []float64, xComponents int, yComponents int) {
+	height := rgba.Bounds().Max.Y
+	width := rgba.Bounds().Max.X
 
 	xvalues := make([][]float64, xComponents)
 	for xComponent := 0; xComponent < xComponents; xComponent++ {
@@ -128,7 +128,7 @@ func multiplyBasisFunction(rgba *image.Image, factors []float64, xComponents int
 
 	for y := 0; y < height; y++ {
 		for x := 0; x < width; x++ {
-			rt, gt, bt, _ := (*rgba).At(x, y).RGBA()
+			rt, gt, bt, _ := rgba.At(x, y).RGBA()
 			lr := channelToLinear[rt>>8]
 			lg := channelToLinear[gt>>8]
 			lb := channelToLinear[bt>>8]

encode_test.go

@@ -22,7 +22,7 @@ func TestEncodeFile(t *testing.T) {
 		t.Fatal("could not decode test.png")
 	}
 
-	str, err := blurhash.Encode(4, 3, &loadedImage)
+	str, err := blurhash.Encode(4, 3, loadedImage)
 	if err != nil {
 		t.Fatal(err)
 		return
@@ -53,7 +53,7 @@ func TestEncodeWrongParameters(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(fmt.Sprintf("xComp:%d yComp:%d", tc.xComp, tc.yComp), func(t *testing.T) {
-			_, err := blurhash.Encode(tc.xComp, tc.yComp, &img)
+			_, err := blurhash.Encode(tc.xComp, tc.yComp, img)
 			if err == nil {
 				t.Fatal("should have failed")
 			}
@@ -70,7 +70,7 @@ func TestEncodeEmptyImage(t *testing.T) {
 	var img image.Image
 	img = image.NewNRGBA(image.Rect(0, 0, 100, 100))
 
-	str, err := blurhash.Encode(4, 3, &img)
+	str, err := blurhash.Encode(4, 3, img)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -98,7 +98,7 @@ func TestEncodeSizeFlag(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(fmt.Sprintf("xComp:%d yComp:%d", tc.xComp, tc.yComp), func(t *testing.T) {
-			str, err := blurhash.Encode(tc.xComp, tc.yComp, &img)
+			str, err := blurhash.Encode(tc.xComp, tc.yComp, img)
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -119,7 +119,7 @@ func TestEncodeSingleColor(t *testing.T) {
 	draw.Draw(img, img.Bounds(), &image.Uniform{tcolor}, image.ZP, draw.Src)
 	var img2 image.Image = img
 
-	str, err := blurhash.Encode(1, 1, &img2)
+	str, err := blurhash.Encode(1, 1, img2)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -141,14 +141,14 @@ func BenchmarkEncode(b *testing.B) {
 	}
 
 	for i := 0; i < b.N; i++ {
-		_, _ = blurhash.Encode(4, 3, &loadedImage)
+		_, _ = blurhash.Encode(4, 3, loadedImage)
 	}
 }
 
 func ExampleEncode() {
 	imageFile, _ := os.Open("test.png")
 	loadedImage, _ := png.Decode(imageFile)
-	str, err := blurhash.Encode(4, 3, &loadedImage)
+	str, err := blurhash.Encode(4, 3, loadedImage)
 	if err != nil {
 		// Handle errors
 	}

go.mod

@@ -1,3 +1,3 @@
 module github.com/buckket/go-blurhash
 
-go 1.12
+go 1.14