feat(#3, #5): support image operations

options.go

@@ -1,5 +1,11 @@
 package bimg
 
+/*
+#cgo pkg-config: vips
+#include "vips/vips.h"
+*/
+import "C"
+
 const QUALITY = 80
 
 type Gravity int
@@ -16,6 +22,26 @@ func (i Interpolator) String() string {
 	return interpolations[i]
 }
 
+type Rotation struct {
+	angle int
+}
+
+func (a Rotation) calculate() int {
+	angle := a.angle
+	divisor := angle % 90
+	if divisor != 0 {
+		angle = a.angle - divisor
+	}
+	return angle
+}
+
+type Direction int
+
+const (
+	HORIZONTAL Direction = C.VIPS_DIRECTION_HORIZONTAL
+	VERTICAL   Direction = C.VIPS_DIRECTION_VERTICAL
+)
+
 type Options struct {
 	Height       int
 	Width        int
@@ -23,7 +49,9 @@ type Options struct {
 	Enlarge      bool
 	Extend       int
 	Embed        bool
-	Interpolator Interpolator
-	Gravity      Gravity
 	Quality      int
+	Rotate       int
+	Flip         Direction
+	Gravity      Gravity
+	Interpolator Interpolator
 }

resize.go

@@ -18,7 +18,6 @@ const (
 
 func Resize(buf []byte, o Options) ([]byte, error) {
 	// detect (if possible) the file type
-
 	defer C.vips_thread_shutdown()
 
 	image, err := vipsRead(buf)
@@ -26,16 +25,6 @@ func Resize(buf []byte, o Options) ([]byte, error) {
 		return nil, err
 	}
 
-	//var tmpImage *C.struct__VipsImage
-	/*
-		// feed it
-		imageLength := C.size_t(len(buf))
-		imageBuf := unsafe.Pointer(&buf[0])
-		debug("buffer: %s", buf[0])
-
-		C.vips_jpegload_buffer_seq(imageBuf, imageLength, &image)
-	*/
-
 	// defaults
 	if o.Quality == 0 {
 		o.Quality = QUALITY
@@ -46,7 +35,6 @@ func Resize(buf []byte, o Options) ([]byte, error) {
 	inHeight := int(image.Ysize)
 
 	// crop
-
 	if o.Crop {
 		left, top := calculateCrop(inWidth, inHeight, o.Width, o.Height, o.Gravity)
 		o.Width = int(math.Min(float64(inWidth), float64(o.Width)))
@@ -55,31 +43,16 @@ func Resize(buf []byte, o Options) ([]byte, error) {
 		if err != nil {
 			return nil, err
 		}
-		//err := C.vips_extract_area_0(image, &tmpImage, C.int(left), C.int(top), C.int(o.Width), C.int(o.Height))
-		//C.g_object_unref(C.gpointer(image))
-		//image = tmpImage
 	}
 
 	// rotate
-	r := Rotation{180}
+	if o.Rotate > 0 {
-	image, err = Rotate(image, r)
+		image, err = Rotate(image, Rotation{o.Rotate})
-	if err != nil {
+		if err != nil {
-		return nil, err
+			return nil, err
+		}
 	}
 
-	// Finally save
-	//var ptr unsafe.Pointer
-	//length := C.size_t(0)
-
-	//C.vips_jpegsave_custom(image, &ptr, &length, 1, C.int(o.Quality), 0)
-	//C.g_object_unref(C.gpointer(image))
-	//C.g_object_unref(C.gpointer(newImage))
-
-	// get back the buffer
-	//buf = C.GoBytes(ptr, C.int(length))
-	// cleanup
-	//C.g_free(C.gpointer(ptr))
-
 	buf, err = vipsSave(image, vipsSaveOptions{Quality: o.Quality})
 	if err != nil {
 		return nil, err
@@ -89,19 +62,6 @@ func Resize(buf []byte, o Options) ([]byte, error) {
 	return buf, nil
 }
 
-type Rotation struct {
-	angle int
-}
-
-func (a Rotation) calculate() int {
-	angle := a.angle
-	divisor := angle % 90
-	if divisor != 0 {
-		angle = a.angle - divisor
-	}
-	return angle
-}
-
 func Rotate(image *C.struct__VipsImage, r Rotation) (*C.struct__VipsImage, error) {
 	//vips := &Vips{}
 	return vipsRotate(image, r.calculate())

resize_test.go

@@ -8,7 +8,7 @@ import (
 )
 
 func TestResize(t *testing.T) {
-	options := Options{Width: 800, Height: 600, Crop: false}
+	options := Options{Width: 800, Height: 600, Crop: false, Rotate: 270}
 	img, err := os.Open("fixtures/space.jpg")
 	if err != nil {
 		t.Fatal(err)

type.go

@@ -1,5 +1,14 @@
 package bimg
 
+const (
+	UNKNOWN = "unknown"
+	JPEG    = "jpeg"
+	WEBP    = "webp"
+	PNG     = "png"
+	TIFF    = "tiff"
+	MAGICK  = "magick"
+)
+
 type Type struct {
 	Name string
 	Mime string

vips.go

@@ -9,6 +9,7 @@ import "C"
 import (
 	"errors"
 	"runtime"
+	"strings"
 	"unsafe"
 )
 
@@ -44,9 +45,24 @@ func vipsRotate(image *C.struct__VipsImage, degrees int) (*C.struct__VipsImage,
 	return out, nil
 }
 
+func vipsFlip(image *C.struct__VipsImage, direction Direction) (*C.struct__VipsImage, error) {
+	var out *C.struct__VipsImage
+
+	err := C.vips_flip_seq(image, &out)
+	C.g_object_unref(C.gpointer(image))
+	if err != 0 {
+		return nil, vipsError()
+	}
+	defer C.g_object_unref(C.gpointer(out))
+
+	return out, nil
+}
+
 func vipsRead(buf []byte) (*C.struct__VipsImage, error) {
 	var image *C.struct__VipsImage
 
+	debug("Format: %s", vipsImageType(buf))
+
 	// feed it
 	length := C.size_t(len(buf))
 	imageBuf := unsafe.Pointer(&buf[0])
@@ -75,6 +91,34 @@ type vipsSaveOptions struct {
 	Quality int
 }
 
+func vipsImageType(buf []byte) string {
+	imageType := UNKNOWN
+
+	length := C.size_t(len(buf))
+	imageBuf := unsafe.Pointer(&buf[0])
+	bufferType := C.GoString(C.vips_foreign_find_load_buffer(imageBuf, length))
+
+	switch {
+	case strings.HasSuffix(bufferType, "JpegBuffer"):
+		imageType = JPEG
+		break
+	case strings.HasSuffix(bufferType, "PngBuffer"):
+		imageType = PNG
+		break
+	case strings.HasSuffix(bufferType, "TiffBuffer"):
+		imageType = TIFF
+		break
+	case strings.HasSuffix(bufferType, "WebpBuffer"):
+		imageType = WEBP
+		break
+	case strings.HasSuffix(bufferType, "MagickBuffer"):
+		imageType = MAGICK
+		break
+	}
+
+	return imageType
+}
+
 func vipsSave(image *C.struct__VipsImage, o vipsSaveOptions) ([]byte, error) {
 	var ptr unsafe.Pointer
 	length := C.size_t(0)

vips.h

@@ -20,6 +20,13 @@ vips_jpegload_buffer_seq(void *buf, size_t len, VipsImage **out)
 	return vips_jpegload_buffer(buf, len, out, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
 };
 
+VipsImage*
+vips_image_buffer_seq(void *buf, size_t len)
+{
+	// todo: handle postclose callback
+	return vips_image_new_from_buffer(buf, len, "access", VIPS_ACCESS_SEQUENTIAL, NULL);
+};
+
 int
 vips_jpegload_buffer_shrink(void *buf, size_t len, VipsImage **out, int shrink)
 {
@@ -32,6 +39,12 @@ 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)
 {
@@ -48,7 +61,7 @@ int
 vips_copy_0(VipsImage *in, VipsImage **out)
 {
 	return vips_copy(in, out, NULL);
-}
+};
 
 int
 vips_rotate(VipsImage *in, VipsImage **buf, int angle)
@@ -64,13 +77,13 @@ vips_rotate(VipsImage *in, VipsImage **buf, int angle)
   }
 
 	return vips_rot(in, buf, rotate, NULL);
-}
+};
 
 int
 vips_embed_extend(VipsImage *in, VipsImage **out, int left, int top, int width, int height, int extend)
 {
 	return vips_embed(in, out, left, top, width, height, "extend", extend, NULL);
-}
+};
 
 int
 vips_colourspace_0(VipsImage *in, VipsImage **out, VipsInterpretation space)
@@ -82,10 +95,10 @@ int
 vips_extract_area_0(VipsImage *in, VipsImage **out, int left, int top, int width, int height)
 {
 	return vips_extract_area(in, out, left, top, width, height, NULL);
-}
+};
 
 int
 vips_jpegsave_custom(VipsImage *in, void **buf, size_t *len, int strip, int quality, int interlace)
 {
 	return vips_jpegsave_buffer(in, buf, len, "strip", strip, "Q", quality, "optimize_coding", TRUE, "interlace", interlace, NULL);
-}
+};