Adjust image dimensions for exif orientation (#5188)

go.mod

@@ -38,6 +38,7 @@ require (
 	github.com/natefinch/pie v0.0.0-20170715172608-9a0d72014007
 	github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8
 	github.com/remeh/sizedwaitgroup v1.0.0
+	github.com/rwcarlsen/goexif v0.0.0-20190401172101-9e8deecbddbd
 	github.com/shurcooL/graphql v0.0.0-20181231061246-d48a9a75455f
 	github.com/sirupsen/logrus v1.9.3
 	github.com/spf13/cast v1.6.0

go.sum

@@ -590,6 +590,8 @@ github.com/rs/zerolog v1.30.0/go.mod h1:/tk+P47gFdPXq4QYjvCmT5/Gsug2nagsFWBWhAiS
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/rwcarlsen/goexif v0.0.0-20190401172101-9e8deecbddbd h1:CmH9+J6ZSsIjUK3dcGsnCnO41eRBOnY12zwkn5qVwgc=
+github.com/rwcarlsen/goexif v0.0.0-20190401172101-9e8deecbddbd/go.mod h1:hPqNNc0+uJM6H+SuU8sEs5K5IQeKccPqeSjfgcKGgPk=
 github.com/ryanuber/columnize v0.0.0-20160712163229-9b3edd62028f/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/ryanuber/columnize v2.1.0+incompatible/go.mod h1:sm1tb6uqfes/u+d4ooFouqFdy9/2g9QGwK3SQygK0Ts=
 github.com/ryanuber/go-glob v1.0.0/go.mod h1:807d1WSdnB0XRJzKNil9Om6lcp/3a0v4qIHxIXzX/Yc=

pkg/file/image/orientation.go

@@ -0,0 +1,75 @@
+package image
+
+import (
+	"errors"
+	"fmt"
+	"io"
+
+	"github.com/rwcarlsen/goexif/exif"
+	"github.com/stashapp/stash/pkg/logger"
+	"github.com/stashapp/stash/pkg/models"
+)
+
+func adjustForOrientation(fs models.FS, path string, f *models.ImageFile) {
+	isFlipped, err := areDimensionsFlipped(fs, path)
+	if err != nil {
+		logger.Warnf("Error determining image orientation for %s: %v", path, err)
+		// isFlipped is false by default
+	}
+
+	if isFlipped {
+		f.Width, f.Height = f.Height, f.Width
+	}
+}
+
+// areDimensionsFlipped returns true if the image dimensions are flipped.
+// This is determined by the EXIF orientation tag.
+func areDimensionsFlipped(fs models.FS, path string) (bool, error) {
+	r, err := fs.Open(path)
+	if err != nil {
+		return false, fmt.Errorf("reading image file %q: %w", path, err)
+	}
+	defer r.Close()
+
+	x, err := exif.Decode(r)
+	if err != nil {
+		if errors.Is(err, io.EOF) {
+			// no exif data
+			return false, nil
+		}
+
+		return false, fmt.Errorf("decoding exif data: %w", err)
+	}
+
+	o, err := x.Get(exif.Orientation)
+	if err != nil {
+		// assume not present
+		return false, nil
+	}
+
+	oo, err := o.Int(0)
+	if err != nil {
+		return false, fmt.Errorf("decoding orientation: %w", err)
+	}
+
+	return isOrientationDimensionsFlipped(oo), nil
+}
+
+// isOrientationDimensionsFlipped returns true if the image orientation is flipped based on the input orientation EXIF value.
+// From https://sirv.com/help/articles/rotate-photos-to-be-upright/
+// 1 = 0 degrees: the correct orientation, no adjustment is required.
+// 2 = 0 degrees, mirrored: image has been flipped back-to-front.
+// 3 = 180 degrees: image is upside down.
+// 4 = 180 degrees, mirrored: image has been flipped back-to-front and is upside down.
+// 5 = 90 degrees: image has been flipped back-to-front and is on its side.
+// 6 = 90 degrees, mirrored: image is on its side.
+// 7 = 270 degrees: image has been flipped back-to-front and is on its far side.
+// 8 = 270 degrees, mirrored: image is on its far side.
+func isOrientationDimensionsFlipped(o int) bool {
+	switch o {
+	case 5, 6, 7, 8:
+		return true
+	default:
+		return false
+	}
+}

pkg/file/image/scan.go

@@ -25,36 +25,17 @@ type Decorator struct {
 func (d *Decorator) Decorate(ctx context.Context, fs models.FS, f models.File) (models.File, error) {
 	base := f.Base()
 
-	decorateFallback := func() (models.File, error) {
-		r, err := fs.Open(base.Path)
-		if err != nil {
-			return f, fmt.Errorf("reading image file %q: %w", base.Path, err)
-		}
-		defer r.Close()
-
-		c, format, err := image.DecodeConfig(r)
-		if err != nil {
-			return f, fmt.Errorf("decoding image file %q: %w", base.Path, err)
-		}
-		return &models.ImageFile{
-			BaseFile: base,
-			Format:   format,
-			Width:    c.Width,
-			Height:   c.Height,
-		}, nil
-	}
-
 	// ignore clips in non-OsFS filesystems as ffprobe cannot read them
 	// TODO - copy to temp file if not an OsFS
 	if _, isOs := fs.(*file.OsFS); !isOs {
 		logger.Debugf("assuming ImageFile for non-OsFS file %q", base.Path)
-		return decorateFallback()
+		return decorateFallback(fs, f)
 	}
 
 	probe, err := d.FFProbe.NewVideoFile(base.Path)
 	if err != nil {
 		logger.Warnf("File %q could not be read with ffprobe: %s, assuming ImageFile", base.Path, err)
-		return decorateFallback()
+		return decorateFallback(fs, f)
 	}
 
 	// Fallback to catch non-animated avif images that FFProbe detects as video files
@@ -79,12 +60,53 @@ func (d *Decorator) Decorate(ctx context.Context, fs models.FS, f models.File) (
 		return videoFileDecorator.Decorate(ctx, fs, f)
 	}
 
-	return &models.ImageFile{
+	ret := &models.ImageFile{
 		BaseFile: base,
 		Format:   probe.VideoCodec,
 		Width:    probe.Width,
 		Height:   probe.Height,
-	}, nil
+	}
+
+	adjustForOrientation(fs, base.Path, ret)
+
+	return ret, nil
+}
+
+func decodeConfig(fs models.FS, path string) (config image.Config, format string, err error) {
+	r, err := fs.Open(path)
+	if err != nil {
+		err = fmt.Errorf("reading image file %q: %w", path, err)
+		return
+	}
+	defer r.Close()
+
+	config, format, err = image.DecodeConfig(r)
+	if err != nil {
+		err = fmt.Errorf("decoding image file %q: %w", path, err)
+		return
+	}
+	return
+}
+
+func decorateFallback(fs models.FS, f models.File) (models.File, error) {
+	base := f.Base()
+	path := base.Path
+
+	c, format, err := decodeConfig(fs, path)
+	if err != nil {
+		return f, err
+	}
+
+	ret := &models.ImageFile{
+		BaseFile: base,
+		Format:   format,
+		Width:    c.Width,
+		Height:   c.Height,
+	}
+
+	adjustForOrientation(fs, path, ret)
+
+	return ret, nil
 }
 
 func (d *Decorator) IsMissingMetadata(ctx context.Context, fs models.FS, f models.File) bool {