feat(thumbnails): optional libvips based thumbnail generation

Can be enabled by setting the 'enable_vips' tag on 'go build'

services/thumbnails/pkg/preprocessor/preprocessor_imaging.go

@@ -1,3 +1,5 @@
+//go:build !enable_vips
+
 package preprocessor
 
 import (

services/thumbnails/pkg/preprocessor/preprocessor_vips.go

@@ -0,0 +1,20 @@
+//go:build enable_vips
+
+package preprocessor
+
+import (
+	"io"
+
+	"github.com/davidbyttow/govips/v2/vips"
+)
+
+func init() {
+	vips.LoggingSettings(nil, vips.LogLevelError)
+}
+
+type ImageDecoder struct{}
+
+func (v ImageDecoder) Convert(r io.Reader) (interface{}, error) {
+	img, err := vips.NewImageFromReader(r)
+	return img, err
+}

services/thumbnails/pkg/thumbnail/encoding_imaging.go

@@ -1,3 +1,5 @@
+//go:build !enable_vips
+
 package thumbnail
 
 import (

services/thumbnails/pkg/thumbnail/encoding_vips.go

@@ -0,0 +1,66 @@
+//go:build enable_vips
+
+package thumbnail
+
+import (
+	"io"
+
+	"github.com/davidbyttow/govips/v2/vips"
+	"github.com/owncloud/ocis/v2/services/thumbnails/pkg/errors"
+)
+
+// PngEncoder encodes to png
+type PngEncoder struct{}
+
+// Encode encodes to png format
+func (e PngEncoder) Encode(w io.Writer, img interface{}) error {
+	m, ok := img.(*vips.ImageRef)
+	if !ok {
+		return errors.ErrInvalidType
+	}
+
+	buf, _, err := m.ExportPng(vips.NewPngExportParams())
+	if err != nil {
+		return err
+	}
+	_, err = w.Write(buf)
+	return err
+}
+
+// Types returns the png suffix
+func (e PngEncoder) Types() []string {
+	return []string{typePng}
+}
+
+// MimeType returns the mimetype for png files.
+func (e PngEncoder) MimeType() string {
+	return "image/png"
+}
+
+// JpegEncoder encodes to jpg
+type JpegEncoder struct{}
+
+// Encode encodes to jpg
+func (e JpegEncoder) Encode(w io.Writer, img interface{}) error {
+	m, ok := img.(*vips.ImageRef)
+	if !ok {
+		return errors.ErrInvalidType
+	}
+
+	buf, _, err := m.ExportJpeg(vips.NewJpegExportParams())
+	if err != nil {
+		return err
+	}
+	_, err = w.Write(buf)
+	return err
+}
+
+// Types returns the jpg suffixes.
+func (e JpegEncoder) Types() []string {
+	return []string{typeJpeg, typeJpg}
+}
+
+// MimeType returns the mimetype for jpg files.
+func (e JpegEncoder) MimeType() string {
+	return "image/jpeg"
+}

services/thumbnails/pkg/thumbnail/generator_simple.go

@@ -1,3 +1,5 @@
+//go:build !enable_vips
+
 package thumbnail
 
 import (

services/thumbnails/pkg/thumbnail/generator_vips.go

@@ -0,0 +1,62 @@
+//go:build enable_vips
+
+package thumbnail
+
+import (
+	"image"
+	"strings"
+
+	"github.com/davidbyttow/govips/v2/vips"
+	"github.com/owncloud/ocis/v2/services/thumbnails/pkg/errors"
+)
+
+// SimpleGenerator is the default image generator and is used for all image types expect gif.
+type SimpleGenerator struct {
+	crop    vips.Interesting
+	size    vips.Size
+	process string
+}
+
+func NewSimpleGenerator(filetype, process string) (SimpleGenerator, error) {
+	switch strings.ToLower(process) {
+	case "thumbnail":
+		return SimpleGenerator{crop: vips.InterestingAttention, process: process, size: vips.SizeBoth}, nil
+	case "fit":
+		return SimpleGenerator{crop: vips.InterestingNone, process: process, size: vips.SizeBoth}, nil
+	case "resize":
+		return SimpleGenerator{crop: vips.InterestingNone, process: process, size: vips.SizeForce}, nil
+	default:
+		return SimpleGenerator{crop: vips.InterestingNone, process: process}, nil
+	}
+}
+
+// ProcessorID returns the processor identification.
+func (g SimpleGenerator) ProcessorID() string {
+	return g.process
+}
+
+// Generate generates a alternative image version.
+func (g SimpleGenerator) Generate(size image.Rectangle, img interface{}) (interface{}, error) {
+	m, ok := img.(*vips.ImageRef)
+	if !ok {
+		return nil, errors.ErrInvalidType
+	}
+
+	if err := m.ThumbnailWithSize(size.Dx(), 0, g.crop, g.size); err != nil {
+		return nil, err
+	}
+
+	if err := m.RemoveMetadata(); err != nil {
+		return nil, err
+	}
+
+	return m, nil
+}
+
+func (g SimpleGenerator) Dimensions(img interface{}) (image.Rectangle, error) {
+	m, ok := img.(*vips.ImageRef)
+	if !ok {
+		return image.Rectangle{}, errors.ErrInvalidType
+	}
+	return image.Rect(0, 0, m.Width(), m.Height()), nil
+}