Merge pull request #9 from davidbyttow/d/transform

Implements new transform API

.travis.yml

@@ -64,7 +64,7 @@ script:
   - diff -u <(echo -n) <(gofmt -s -d ./)
   - diff -u <(echo -n) <(go vet ./)
 #  - diff -u <(echo -n) <(golint ./)
-  - go test -v -race -covermode=atomic -coverprofile=coverage.out
+  - go test -short -v -race -covermode=atomic -coverprofile=coverage.out
 
 after_success:
   - goveralls -coverprofile=coverage.out -service=travis-ci

bridge.go

@@ -11,7 +11,8 @@ import (
 )
 
 const (
-	defaultQuality = 80
+	defaultQuality     = 90
+	defaultCompression = 6
 )
 
 var stringBuffer4096 = fixedString(4096)
@@ -123,34 +124,38 @@ func vipsCallOperation(operation *C.VipsOperation, options []*Option) error {
 	return nil
 }
 
-func vipsPrepareForExport(image *C.VipsImage, params *ExportParams) (*C.VipsImage, error) {
-	var outImage *C.VipsImage
-
+func vipsPrepareForExport(input *C.VipsImage, params *ExportParams) (*C.VipsImage, error) {
 	if params.StripProfile {
-		C.remove_icc_profile(image)
+		C.remove_icc_profile(input)
 	}
 
 	if params.Quality == 0 {
 		params.Quality = defaultQuality
 	}
 
+	if params.Compression == 0 {
+		params.Compression = defaultCompression
+	}
+
 	// Use a default interpretation and cast it to C type
 	if params.Interpretation == 0 {
-		params.Interpretation = InterpretationSRGB
+		params.Interpretation = Interpretation(input.Type)
 	}
 
 	interpretation := C.VipsInterpretation(params.Interpretation)
 
 	// Apply the proper colour space
-	if int(C.is_colorspace_supported(image)) == 1 {
-		err := C.to_colorspace(image, &outImage, interpretation)
+	if int(C.is_colorspace_supported(input)) == 1 && interpretation != input.Type {
+		var out *C.VipsImage
+		defer C.g_object_unref(C.gpointer(input))
+		err := C.to_colorspace(input, &out, interpretation)
 		if int(err) != 0 {
 			return nil, handleVipsError()
 		}
-		image = outImage
+		input = out
 	}
 
-	return image, nil
+	return input, nil
 }
 
 func vipsLoadFromBuffer(buf []byte) (*C.VipsImage, ImageType, error) {
@@ -287,6 +292,26 @@ func vipsShrink(input *C.VipsImage, shrink int) (*C.VipsImage, error) {
 	return image, nil
 }
 
+func vipsFlattenBackground(input *C.VipsImage, color Color) (*C.VipsImage, error) {
+	var image *C.VipsImage
+	defer C.g_object_unref(C.gpointer(input))
+
+	bg := [3]C.double{
+		C.double(color.R),
+		C.double(color.G),
+		C.double(color.B),
+	}
+
+	if int(C.has_alpha_channel(input)) > 0 {
+		err := C.flatten_image_background(input, &image, bg[0], bg[1], bg[2])
+		if int(err) != 0 {
+			return nil, handleVipsError()
+		}
+	}
+
+	return image, nil
+}
+
 func handleVipsError() error {
 	defer C.vips_thread_shutdown()
 	defer C.vips_error_clear()

bridge.h

@@ -45,3 +45,11 @@ int flatten_image_background(VipsImage *in, VipsImage **out, double r, double g,
 int transform_image(VipsImage *in, VipsImage **out, double a, double b, double c, double d, VipsInterpolate *interpolator);
 
 void gobject_set_property(VipsObject* object, const char* name, const GValue* value);
+
+static int has_alpha_channel(VipsImage *image) {
+	return (
+		(image->Bands == 2 && image->Type == VIPS_INTERPRETATION_B_W) ||
+		(image->Bands == 4 && image->Type != VIPS_INTERPRETATION_CMYK) ||
+		(image->Bands == 5 && image->Type == VIPS_INTERPRETATION_CMYK)
+	) ? 1 : 0;
+}

examples/embed/embed.go

@@ -27,9 +27,11 @@ func main() {
 }
 
 func embed(inputFile, outputFile string) error {
-	return vips.NewPipeline().
+	_, err := vips.NewTransform().
 		LoadFile(inputFile).
 		PadStrategy(vips.ExtendBlack).
 		Resize(1200, 1200).
-		OutputFile(outputFile)
+		OutputFile(outputFile).
+		Apply()
+	return err
 }

examples/invert/invert.go

@@ -27,8 +27,10 @@ func main() {
 }
 
 func invert(inputFile, outputFile string) error {
-	return vips.NewPipeline().
+	_, err := vips.NewTransform().
 		LoadFile(inputFile).
 		Invert().
-		OutputFile(outputFile)
+		OutputFile(outputFile).
+		Apply()
+	return err
 }

examples/resize/resize.go

@@ -27,8 +27,10 @@ func main() {
 }
 
 func resize(inputFile, outputFile string) error {
-	return vips.NewPipeline().
+	_, err := vips.NewTransform().
 		LoadFile(inputFile).
 		Reduce(0.2).
-		OutputFile(outputFile)
+		OutputFile(outputFile).
+		Apply()
+	return err
 }

image.go

@@ -6,6 +6,7 @@ import "C"
 
 import (
 	"errors"
+	"io"
 	"io/ioutil"
 	"runtime"
 	"unsafe"
@@ -18,6 +19,15 @@ type ImageRef struct {
 	format ImageType
 }
 
+// LoadImage loads an ImageRef from the given reader
+func LoadImage(r io.Reader) (*ImageRef, error) {
+	buf, err := ioutil.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+	return NewImageFromBuffer(buf)
+}
+
 // NewImageFromFile loads an image from file and creates a new ImageRef
 func NewImageFromFile(file string) (*ImageRef, error) {
 	startupIfNeeded()
@@ -31,6 +41,7 @@ func NewImageFromFile(file string) (*ImageRef, error) {
 
 // NewImageFromBuffer loads an image buffer and creates a new Image
 func NewImageFromBuffer(buf []byte) (*ImageRef, error) {
+	defer runtime.KeepAlive(buf)
 	startupIfNeeded()
 
 	image, format, err := vipsLoadFromBuffer(buf)

leak_test.go

@@ -20,10 +20,10 @@ var (
 		vips.ResizeStrategyEmbed,
 	}
 	sizes = []size{
-		size{100, 100},
-		size{500, 0},
-		size{0, 500},
-		size{1000, 1000},
+		{100, 100},
+		{500, 0},
+		{0, 500},
+		{1000, 1000},
 	}
 	formats = []vips.ImageType{
 		vips.ImageTypeJPEG,
@@ -35,7 +35,7 @@ type transform struct {
 	Resize  vips.ResizeStrategy
 	Width   int
 	Height  int
-	Flip    vips.Direction
+	Flip    vips.FlipDirection
 	Format  vips.ImageType
 	Zoom    int
 	Blur    float64
@@ -57,7 +57,7 @@ func TestCleanup(t *testing.T) {
 					Resize:  resize,
 					Width:   size.w,
 					Height:  size.h,
-					Flip:    vips.DirectionHorizontal,
+					Flip:    vips.FlipBoth,
 					Kernel:  vips.KernelLanczos3,
 					Format:  format,
 					Blur:    4,
@@ -77,7 +77,7 @@ func TestCleanup(t *testing.T) {
 			go func(i int) {
 				defer wg.Done()
 
-				buf, err := vips.NewPipeline().
+				buf, err := vips.NewTransform().
 					LoadFile("fixtures/canyon.jpg").
 					ResizeStrategy(transform.Resize).
 					Resize(transform.Width, transform.Height).
@@ -88,7 +88,8 @@ func TestCleanup(t *testing.T) {
 					Interpolator(transform.Interp).
 					Zoom(transform.Zoom, transform.Zoom).
 					Quality(transform.Quality).
-					Output()
+					OutputBytes().
+					Apply()
 				require.NoError(t, err)
 
 				image, err := vips.NewImageFromBuffer(buf)