feat: support multiple outputs

image.go

@@ -9,7 +9,7 @@ func (i *Image) Resize(width int, height int) ([]byte, error) {
 		Width:  width,
 		Height: height,
 	}
-	return Resize(i.buffer, options)
+	return i.Process(options)
 }
 
 func (i *Image) Extract(top int, left int, width int, height int) ([]byte, error) {
@@ -19,22 +19,36 @@ func (i *Image) Extract(top int, left int, width int, height int) ([]byte, error
 		Top:    top,
 		Left:   left,
 	}
-	return Resize(i.buffer, options)
+	return i.Process(options)
 }
 
-func (i *Image) Rotate(degrees Angle) ([]byte, error) {
+func (i *Image) Rotate(a Angle) ([]byte, error) {
-	options := Options{Rotate: degrees}
+	options := Options{Rotate: a}
-	return Resize(i.buffer, options)
+	return i.Process(options)
 }
 
 func (i *Image) Flip() ([]byte, error) {
 	options := Options{Flip: VERTICAL}
-	return Resize(i.buffer, options)
+	return i.Process(options)
 }
 
 func (i *Image) Flop() ([]byte, error) {
 	options := Options{Flip: HORIZONTAL}
-	return Resize(i.buffer, options)
+	return i.Process(options)
+}
+
+func (i *Image) Convert(t ImageType) ([]byte, error) {
+	options := Options{Type: t}
+	return i.Process(options)
+}
+
+func (i *Image) Process(o Options) ([]byte, error) {
+	image, err := Resize(i.buffer, o)
+	if err != nil {
+		return nil, err
+	}
+	i.buffer = image
+	return image, nil
 }
 
 func (i *Image) Type() string {

image_test.go

@@ -0,0 +1,20 @@
+package bimg
+
+import (
+	"io/ioutil"
+	"os"
+	"path"
+	"testing"
+)
+
+func TestImageResize(t *testing.T) {
+	data, _ := os.Open(path.Join("fixtures/test.jpg"))
+	buf, err := ioutil.ReadAll(data)
+
+	image := NewImage(buf)
+
+	buf, err = image.Resize(300, 240)
+	if err != nil {
+		t.Errorf("Cannot process the image: %#v", err)
+	}
+}

options.go

@@ -48,6 +48,8 @@ type Options struct {
 	Extend       int
 	Embed        bool
 	Quality      int
+	Compression  int
+	Type         ImageType
 	Rotate       Angle
 	Flip         Direction
 	Gravity      Gravity

resize.go

@@ -7,6 +7,7 @@ package bimg
 import "C"
 
 import (
+	"errors"
 	"math"
 )
 
@@ -27,7 +28,7 @@ const (
 func Resize(buf []byte, o Options) ([]byte, error) {
 	defer C.vips_thread_shutdown()
 
-	image, err := vipsRead(buf)
+	image, imageType, err := vipsRead(buf)
 	if err != nil {
 		return nil, err
 	}
@@ -36,6 +37,12 @@ func Resize(buf []byte, o Options) ([]byte, error) {
 	if o.Quality == 0 {
 		o.Quality = QUALITY
 	}
+	if o.Compression == 0 {
+		o.Compression = 6
+	}
+	if o.Type == 0 {
+		o.Type = imageType
+	}
 
 	// get WxH
 	inWidth := int(image.Xsize)
@@ -74,7 +81,17 @@ func Resize(buf []byte, o Options) ([]byte, error) {
 		}
 	}
 
-	buf, err = vipsSave(image, vipsSaveOptions{Quality: o.Quality})
+	if IsTypeSupported(o.Type) == false {
+		return nil, errors.New("Unsupported image output type")
+	}
+
+	saveOptions := vipsSaveOptions{
+		Quality:     o.Quality,
+		Type:        o.Type,
+		Compression: o.Compression,
+	}
+
+	buf, err = vipsSave(image, saveOptions)
 	if err != nil {
 		return nil, err
 	}

resize_test.go

@@ -33,3 +33,31 @@ func TestResize(t *testing.T) {
 		t.Fatal("Cannot save the image")
 	}
 }
+
+func TestConvert(t *testing.T) {
+	options := Options{Width: 640, Height: 480, Crop: false, Type: PNG}
+	img, err := os.Open("fixtures/test.jpg")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer img.Close()
+
+	buf, err := ioutil.ReadAll(img)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	newImg, err := Resize(buf, options)
+	if err != nil {
+		t.Errorf("Resize(imgData, %#v) error: %#v", options, err)
+	}
+
+	if DetermineImageType(newImg) != PNG {
+		t.Fatal("Image is not png")
+	}
+
+	err = ioutil.WriteFile("result.png", newImg, 0644)
+	if err != nil {
+		t.Fatal("Cannot save the image")
+	}
+}

type.go

@@ -1,7 +1,9 @@
 package bimg
 
+type ImageType int
+
 const (
-	UNKNOWN = iota
+	UNKNOWN ImageType = iota
 	JPEG
 	WEBP
 	PNG
@@ -9,7 +11,7 @@ const (
 	MAGICK
 )
 
-func DetermineImageType(buf []byte) int {
+func DetermineImageType(buf []byte) ImageType {
 	return vipsImageType(buf)
 }
 
@@ -28,7 +30,7 @@ func DetermineImageTypeName(buf []byte) string {
 		imageType = "png"
 		break
 	case imageCode == TIFF:
-		imageType = "png"
+		imageType = "tiff"
 		break
 	case imageCode == MAGICK:
 		imageType = "magick"
@@ -37,3 +39,12 @@ func DetermineImageTypeName(buf []byte) string {
 
 	return imageType
 }
+
+func IsTypeSupported(t ImageType) bool {
+	return t == JPEG || t == PNG || t == WEBP
+}
+
+func IsTypeNameSupported(t string) bool {
+	return t == "jpeg" || t == "jpg" ||
+		t == "png" || t == "webp"
+}

type_test.go

@@ -0,0 +1,50 @@
+package bimg
+
+import (
+	"io/ioutil"
+	"os"
+	"path"
+	"testing"
+)
+
+func TestDeterminateImageType(t *testing.T) {
+	files := []struct {
+		name     string
+		expected ImageType
+	}{
+		{"test.jpg", JPEG},
+		{"test.png", PNG},
+		{"test.webp", WEBP},
+	}
+
+	for _, file := range files {
+		img, _ := os.Open(path.Join("fixtures", file.name))
+		buf, _ := ioutil.ReadAll(img)
+		defer img.Close()
+
+		if DetermineImageType(buf) != file.expected {
+			t.Fatal("Image type is not valid")
+		}
+	}
+}
+
+func TestDeterminateImageTypeName(t *testing.T) {
+	files := []struct {
+		name     string
+		expected string
+	}{
+		{"test.jpg", "jpeg"},
+		{"test.png", "png"},
+		{"test.webp", "webp"},
+	}
+
+	for _, file := range files {
+		img, _ := os.Open(path.Join("fixtures", file.name))
+		buf, _ := ioutil.ReadAll(img)
+		defer img.Close()
+
+		if DetermineImageTypeName(buf) != file.expected {
+			t.Fatal("Image type is not valid")
+		}
+	}
+}

vips.go

@@ -60,12 +60,12 @@ func vipsFlip(image *C.struct__VipsImage, direction Direction) (*C.struct__VipsI
 	return out, nil
 }
 
-func vipsRead(buf []byte) (*C.struct__VipsImage, error) {
+func vipsRead(buf []byte) (*C.struct__VipsImage, ImageType, error) {
 	var image *C.struct__VipsImage
 	imageType := vipsImageType(buf)
 
 	if imageType == UNKNOWN {
-		return nil, errors.New("Input buffer contains unsupported image format")
+		return nil, UNKNOWN, errors.New("Input buffer contains unsupported image format")
 	}
 
 	// feed it
@@ -75,10 +75,10 @@ func vipsRead(buf []byte) (*C.struct__VipsImage, error) {
 
 	err := C.vips_init_image(imageBuf, length, imageTypeC, &image)
 	if err != 0 {
-		return nil, catchVipsError()
+		return nil, UNKNOWN, catchVipsError()
 	}
 
-	return image, nil
+	return image, imageType, nil
 }
 
 func vipsExtract(image *C.struct__VipsImage, left int, top int, width int, height int) (*C.struct__VipsImage, error) {
@@ -93,7 +93,7 @@ func vipsExtract(image *C.struct__VipsImage, left int, top int, width int, heigh
 	return buf, nil
 }
 
-func vipsImageType(buf []byte) int {
+func vipsImageType(buf []byte) ImageType {
 	imageType := UNKNOWN
 
 	length := C.size_t(len(buf))
@@ -126,18 +126,32 @@ func vipsExifOrientation(image *C.struct__VipsImage) int {
 }
 
 type vipsSaveOptions struct {
-	Quality int
+	Quality     int
+	Compression int
+	Type        ImageType
 }
 
 func vipsSave(image *C.struct__VipsImage, o vipsSaveOptions) ([]byte, error) {
 	var ptr unsafe.Pointer
 	length := C.size_t(0)
+	err := C.int(0)
 
-	err := C.vips_jpegsave_custom(image, &ptr, &length, 1, C.int(o.Quality), 0)
+	switch {
+	case o.Type == PNG:
+		err = C.vips_pngsave_custom(image, &ptr, &length, 1, C.int(o.Compression), C.int(o.Quality), 0)
+		break
+	case o.Type == WEBP:
+		err = C.vips_webpsave_custom(image, &ptr, &length, 1, C.int(o.Quality), 0)
+		break
+	default:
+		err = C.vips_jpegsave_custom(image, &ptr, &length, 1, C.int(o.Quality), 0)
+		break
+	}
+
+	C.g_object_unref(C.gpointer(image))
 	if err != 0 {
 		return nil, catchVipsError()
 	}
-	C.g_object_unref(C.gpointer(image))
 
 	buf := C.GoBytes(ptr, C.int(length))
 	// cleanup

vips.h

@@ -36,24 +36,12 @@ vips_jpegload_buffer_shrink(void *buf, size_t len, VipsImage **out, int shrink)
 	return vips_jpegload_buffer(buf, len, out, "shrink", shrink, NULL);
 };
 
-int
-vips_webpload_buffer_seq(void *buf, size_t len, VipsImage **out)
-{
-	return vips_webpload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
-};
-
 int
 vips_flip_seq(VipsImage *in, VipsImage **out)
 {
 	return vips_flip(in, out, VIPS_DIRECTION_HORIZONTAL, NULL);
 };
 
-int
-vips_pngload_buffer_seq(void *buf, size_t len, VipsImage **out)
-{
-	return vips_pngload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
-};
-
 int
 vips_shrink_0(VipsImage *in, VipsImage **out, double xshrink, double yshrink)
 {
@@ -82,32 +70,6 @@ vips_rotate(VipsImage *in, VipsImage **buf, int angle)
 	return vips_rot(in, buf, rotate, NULL);
 };
 
-int
-vips_init_image(void *buf, size_t len, int imageType, VipsImage **out) {
- 	int code = 1;
-
-  if (imageType == JPEG) {
-    code = vips_jpegload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
-  } else if (imageType == PNG) {
-    code = vips_pngload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
-  } else if (imageType == WEBP) {
-    code = vips_webpload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
-  } else if (imageType == TIFF) {
-    code = vips_tiffload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
-#if (VIPS_MAJOR_VERSION >= 8)
-  } else if (imageType == MAGICK) {
-    code = vips_magickload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
-#endif
-  }
-
-  if (out != NULL) {
-  	// Listen for "postclose" signal to delete input buffer
-  	//g_signal_connect(out, "postclose", G_CALLBACK(vips_malloc_cb), buf);
-	}
-
-  return code;
-};
-
 int
 vips_exif_orientation(VipsImage *image) {
   int orientation = 0;
@@ -144,3 +106,47 @@ vips_jpegsave_custom(VipsImage *in, void **buf, size_t *len, int strip, int qual
 {
 	return vips_jpegsave_buffer(in, buf, len, "strip", strip, "Q", quality, "optimize_coding", TRUE, "interlace", interlace, NULL);
 };
+
+int
+vips_pngsave_custom(VipsImage *in, void **buf, size_t *len, int strip, int compression, int quality, int interlace)
+{
+#if (VIPS_MAJOR_VERSION >= 8 || (VIPS_MAJOR_VERSION >= 7 && VIPS_MINOR_VERSION >= 42))
+  return vips_pngsave_buffer(in, buf, len, "strip", FALSE, "compression", compression,
+  	"interlace", interlace, "filter", VIPS_FOREIGN_PNG_FILTER_NONE, NULL);
+#else
+  return vips_pngsave_buffer(image, buf, len, "strip", FALSE, "compression", compression,
+		"interlace", interlace, NULL);
+#endif
+};
+
+int
+vips_webpsave_custom(VipsImage *in, void **buf, size_t *len, int strip, int quality, int interlace)
+{
+	return vips_webpsave_buffer(in, buf, len, "strip", strip, "Q", quality, "optimize_coding", TRUE, "interlace", interlace, NULL);
+};
+
+int
+vips_init_image(void *buf, size_t len, int imageType, VipsImage **out) {
+ 	int code = 1;
+
+  if (imageType == JPEG) {
+    code = vips_jpegload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
+  } else if (imageType == PNG) {
+    code = vips_pngload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
+  } else if (imageType == WEBP) {
+    code = vips_webpload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
+  } else if (imageType == TIFF) {
+    code = vips_tiffload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
+#if (VIPS_MAJOR_VERSION >= 8)
+  } else if (imageType == MAGICK) {
+    code = vips_magickload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
+#endif
+  }
+
+  if (out != NULL) {
+  	// Listen for "postclose" signal to delete input buffer
+  	//g_signal_connect(out, "postclose", G_CALLBACK(vips_malloc_cb), buf);
+	}
+
+  return code;
+};