feat(docs): add API and examples

README.md

@@ -58,7 +58,7 @@ bimg performance tests coming soon!
 
 ## API
 
-### Example
+### Examples
 
 ```go
 import (
@@ -66,18 +66,85 @@ import (
   "os"
   "gopkg.in/h2non/bimg.v0"
 )
+```
 
-options := bimg.Options{
+#### Resize
-    Width:        800,
-    Height:       600,
-    Crop:         true,
-    Quality:      95,
-}
 
-newImage, err := bimg.Resize(image, options)
+```go
+buffer, err := bimg.Read("image.jpg")
 if err != nil {
   fmt.Fprintln(os.Stderr, err)
 }
+
+newImage, err := bimg.NewImage(buffer).Resize(800, 600)
+if err != nil {
+  fmt.Fprintln(os.Stderr, err)
+}
+
+size, err := bimg.NewImage(newImage).Size()
+if size.Width == 400 && size.Height == 300 {
+  fmt.Println("The image size is valid")
+}
+
+bimg.Write("new.jpg", newImage)
+```
+
+#### Rotate
+
+```go
+buffer, err := bimg.Read("image.jpg")
+if err != nil {
+  fmt.Fprintln(os.Stderr, err)
+}
+
+newImage, err := bimg.NewImage(buffer).Rotate(90)
+if err != nil {
+  fmt.Fprintln(os.Stderr, err)
+}
+
+bimg.Write("new.jpg", newImage)
+```
+
+#### Convert
+
+```go
+buffer, err := bimg.Read("image.jpg")
+if err != nil {
+  fmt.Fprintln(os.Stderr, err)
+}
+
+newImage, err := bimg.NewImage(buffer).Convert(bimg.PNG)
+if err != nil {
+  fmt.Fprintln(os.Stderr, err)
+}
+
+if bimg.NewImage(newImage).Type() == "png" {
+  fmt.Fprintln(os.Stderr, "The image was converted into png")
+}
+```
+
+#### Process
+
+```go
+options := bimg.Options{
+  Width:        800,
+  Height:       600,
+  Crop:         true,
+  Quality:      95,
+  Rotate:       180,
+}
+
+buffer, err := bimg.Read("image.jpg")
+if err != nil {
+  fmt.Fprintln(os.Stderr, err)
+}
+
+newImage, err := bimg.NewImage(buffer).Process(options)
+if err != nil {
+  fmt.Fprintln(os.Stderr, err)
+}
+
+bimg.Write("new.jpg", newImage)
 ```
 
 #### func  DetermineImageTypeName
@@ -86,6 +153,12 @@ if err != nil {
 func DetermineImageTypeName(buf []byte) string
 ```
 
+#### func  Initialize
+
+```go
+func Initialize()
+```
+
 #### func  IsTypeNameSupported
 
 ```go
@@ -110,6 +183,12 @@ func Read(path string) ([]byte, error)
 func Resize(buf []byte, o Options) ([]byte, error)
 ```
 
+#### func  Shutdown
+
+```go
+func Shutdown()
+```
+
 #### type Angle
 
 ```go
@@ -291,7 +370,7 @@ const (
 )
 ```
 
-#### func DetermineImageType
+#### func  DetermineImageType
 
 ```go
 func DetermineImageType(buf []byte) ImageType
@@ -340,14 +419,6 @@ type Options struct {
 }
 ```
 
-
-#### type Vips
-
-```go
-type Vips struct {
-}
-```
-
 ## License
 
 MIT - Tomas Aparicio

image_test.go

@@ -53,6 +53,19 @@ func TestImageConvert(t *testing.T) {
 	Write("fixtures/test_image_convert_out.png", buf)
 }
 
+func TestImageMetadata(t *testing.T) {
+	data, err := initImage("test.png").Metadata(PNG)
+	if err != nil {
+		t.Errorf("Cannot process the image: %#v", err)
+	}
+	if data.Alpha != true {
+		t.Fatal("Invalid alpha channel")
+	}
+	if data.Size.Width != 400 {
+		t.Fatal("Invalid width size")
+	}
+}
+
 func initImage(file string) *Image {
 	buf, _ := Read(path.Join("fixtures", file))
 	return NewImage(buf)