Merge pull request #61 from cshum/focal

feat(vips): focal filter

imagor.go

@@ -95,8 +95,7 @@ func New(options ...Option) *Imagor {
 	if app.Signer == nil {
 		app.Signer = imagorpath.NewDefaultSigner("")
 	}
-	// cast storages into loaders
-	app.ResultLoaders = loaderSlice(app.ResultStorages)
+	app.ResultLoaders = append(loaderSlice(app.ResultStorages), app.ResultLoaders...)
 	app.Loaders = append(loaderSlice(app.Storages), app.Loaders...)
 	return app
 }

processor/vipsprocessor/image.go

@@ -3,6 +3,7 @@ package vipsprocessor
 import (
 	"github.com/cshum/imagor"
 	"github.com/davidbyttow/govips/v2/vips"
+	"math"
 )
 
 func (v *VipsProcessor) newThumbnail(
@@ -115,13 +116,30 @@ func (v *VipsProcessor) thumbnail(
 	return v.animatedThumbnailWithCrop(img, width, height, crop, size)
 }
 
+func (v *VipsProcessor) focalThumbnail(img *vips.ImageRef, w, h int, fx, fy float64) (err error) {
+	if float64(w)/float64(h) > float64(img.Width())/float64(img.PageHeight()) {
+		if err = img.Thumbnail(w, v.MaxHeight, vips.InterestingNone); err != nil {
+			return
+		}
+	} else {
+		if err = img.Thumbnail(v.MaxWidth, h, vips.InterestingNone); err != nil {
+			return
+		}
+	}
+	var top, left float64
+	left = float64(img.Width())*fx - float64(w)/2
+	top = float64(img.PageHeight())*fy - float64(h)/2
+	left = math.Max(0, math.Min(left, float64(img.Width()-w)))
+	top = math.Max(0, math.Min(top, float64(img.PageHeight()-h)))
+	return img.ExtractArea(int(left), int(top), w, h)
+}
+
 func (v *VipsProcessor) animatedThumbnailWithCrop(
 	img *vips.ImageRef, w, h int, crop vips.Interesting, size vips.Size,
 ) (err error) {
 	if size == vips.SizeDown && img.Width() < w && img.PageHeight() < h {
 		return
 	}
-	// use ExtractArea for animated cropping
 	var top, left int
 	if float64(w)/float64(h) > float64(img.Width())/float64(img.PageHeight()) {
 		if err = img.ThumbnailWithSize(w, v.MaxHeight, vips.InterestingNone, size); err != nil {

processor/vipsprocessor/process.go

@@ -14,7 +14,7 @@ import (
 )
 
 func (v *VipsProcessor) process(
-	ctx context.Context, img *vips.ImageRef, p imagorpath.Params, load imagor.LoadFunc, thumbnail, stretch, upscale bool,
+	ctx context.Context, img *vips.ImageRef, p imagorpath.Params, load imagor.LoadFunc, thumbnail, stretch, upscale bool, focalRects []focal,
 ) error {
 	if p.Trim {
 		if err := trim(ctx, img, p.TrimBy, p.TrimTolerance); err != nil {
@@ -76,8 +76,19 @@ func (v *VipsProcessor) process(
 					interest = vips.InterestingHigh
 				}
 			}
-			if err := v.thumbnail(img, w, h, interest, vips.SizeBoth); err != nil {
-				return err
+			if p.Smart && len(focalRects) > 0 {
+				focalX, focalY := parseFocalPoint(focalRects...)
+				if err := v.focalThumbnail(
+					img, w, h,
+					focalX/float64(img.Width()),
+					focalY/float64(img.PageHeight()),
+				); err != nil {
+					return err
+				}
+			} else {
+				if err := v.thumbnail(img, w, h, interest, vips.SizeBoth); err != nil {
+					return err
+				}
 			}
 		}
 	}
@@ -124,6 +135,26 @@ func (v *VipsProcessor) process(
 	return nil
 }
 
+type focal struct {
+	Left   float64
+	Right  float64
+	Top    float64
+	Bottom float64
+}
+
+func parseFocalPoint(focalRects ...focal) (focalX, focalY float64) {
+	var sumWeight float64
+	for _, f := range focalRects {
+		sumWeight += (f.Right - f.Left) * (f.Bottom - f.Top)
+	}
+	for _, f := range focalRects {
+		r := (f.Right - f.Left) * (f.Bottom - f.Top) / sumWeight
+		focalX += (f.Left + f.Right) / 2 * r
+		focalY += (f.Top + f.Bottom) / 2 * r
+	}
+	return
+}
+
 func trim(ctx context.Context, img *vips.ImageRef, pos string, tolerance int) error {
 	if IsAnimated(ctx) {
 		// skip animation support

processor/vipsprocessor/vips.go

@@ -117,6 +117,10 @@ func (v *VipsProcessor) Shutdown(_ context.Context) error {
 	return nil
 }
 
+func focalSplit(r rune) bool {
+	return r == 'x' || r == ',' || r == ':'
+}
+
 func (v *VipsProcessor) Process(
 	ctx context.Context, blob *imagor.Bytes, p imagorpath.Params, load imagor.LoadFunc,
 ) (*imagor.Bytes, error) {
@@ -129,6 +133,7 @@ func (v *VipsProcessor) Process(
 		format                = vips.ImageTypeUnknown
 		maxN                  = v.MaxAnimationFrames
 		maxBytes              int
+		focalRects            []focal
 		err                   error
 	)
 	ctx = WithInitImageRefs(ctx)
@@ -173,6 +178,9 @@ func (v *VipsProcessor) Process(
 				thumbnailNotSupported = true
 			}
 			break
+		case "focal":
+			thumbnailNotSupported = true
+			break
 		case "trim":
 			thumbnailNotSupported = true
 			break
@@ -276,6 +284,8 @@ func (v *VipsProcessor) Process(
 	var (
 		quality int
 		pageN   = img.Height() / img.PageHeight()
+		dw      = float64(img.Width())
+		dh      = float64(img.PageHeight())
 	)
 	if format == vips.ImageTypeUnknown {
 		format = img.Format()
@@ -296,9 +306,27 @@ func (v *VipsProcessor) Process(
 		case "autojpg":
 			format = vips.ImageTypeJPEG
 			break
+		case "focal":
+			if args := strings.FieldsFunc(p.Args, focalSplit); len(args) == 4 {
+				f := focal{}
+				f.Left, _ = strconv.ParseFloat(args[0], 64)
+				f.Top, _ = strconv.ParseFloat(args[1], 64)
+				f.Right, _ = strconv.ParseFloat(args[2], 64)
+				f.Bottom, _ = strconv.ParseFloat(args[3], 64)
+				if f.Left < 1 && f.Top < 1 && f.Right <= 1 && f.Bottom <= 1 {
+					f.Left *= dw
+					f.Right *= dw
+					f.Top *= dh
+					f.Bottom *= dh
+				}
+				if f.Right > f.Left && f.Bottom > f.Top {
+					focalRects = append(focalRects, f)
+				}
+			}
+			break
 		}
 	}
-	if err := v.process(ctx, img, p, load, thumbnail, stretch, upscale); err != nil {
+	if err := v.process(ctx, img, p, load, thumbnail, stretch, upscale, focalRects); err != nil {
 		return nil, wrapErr(err)
 	}
 	for {

processor/vipsprocessor/vips_test.go

@@ -65,16 +65,16 @@ type test struct {
 }
 
 func doTests(t *testing.T, resultDir string, tests []test, opts ...Option) {
+	resStorage := filestorage.New(
+		resultDir,
+		filestorage.WithSaveErrIfExists(true),
+	)
 	app := imagor.New(
 		imagor.WithLoaders(filestorage.New(testDataDir)),
 		imagor.WithUnsafe(true),
 		imagor.WithDebug(true),
 		imagor.WithLogger(zap.NewExample()),
 		imagor.WithProcessors(New(opts...)),
-		imagor.WithResultStorages(filestorage.New(
-			resultDir,
-			filestorage.WithSaveErrIfExists(true),
-		)),
 	)
 	require.NoError(t, app.Startup(context.Background()))
 	t.Parallel()
@@ -84,6 +84,7 @@ func doTests(t *testing.T, resultDir string, tests []test, opts ...Option) {
 			app.ServeHTTP(w, httptest.NewRequest(
 				http.MethodGet, fmt.Sprintf("/unsafe/%s", tt.path), nil))
 			assert.Equal(t, 200, w.Code)
+			_ = resStorage.Put(context.Background(), tt.path, imagor.NewBytes(w.Body.Bytes()))
 			path := filepath.Join(resultDir, imagorpath.Normalize(tt.path, nil))
 
 			buf, err := ioutil.ReadFile(path)
@@ -112,6 +113,8 @@ func TestVipsProcessor(t *testing.T) {
 		{"original", "gopher-front.png"},
 		{"resize center", "100x100/filters:quality(70):format(jpeg)/gopher.png"},
 		{"resize smart", "100x100/smart/filters:autojpg()/gopher.png"},
+		{"resize smart focal", "300x100/smart/filters:fill(white):format(jpeg):focal(589x401:1000x814)/gopher.png"},
+		{"resize smart focal float", "300x100/smart/filters:fill(white):format(jpeg):focal(0.35x0.25:0.6x0.3)/gopher.png"},
 		{"resize top", "200x100/top/filters:quality(70):format(tiff)/gopher.png"},
 		{"resize top", "200x100/right/top/gopher.png"},
 		{"resize bottom", "200x100/bottom/gopher.png"},
@@ -151,6 +154,7 @@ func TestVipsProcessor(t *testing.T) {
 		{"original animated", "dancing-banana.gif"},
 		{"crop animated", "30x20:100x150/dancing-banana.gif"},
 		{"crop-percent animated", "0.1x0.2:0.89x0.72/dancing-banana.gif"},
+		{"smart focal animated", "100x30/smart/filters:focal(0.1x0:0.89x0.72)/dancing-banana.gif"},
 		//{"resize center animated", "100x100/dancing-banana.gif"},
 		//{"resize top animated", "200x100/top/dancing-banana.gif"},
 		//{"resize top animated", "200x100/right/top/dancing-banana.gif"},