thumbnail/decodeImage.go

44 lines
761 B
Go
Raw Normal View History

package thumbnail
import (
"image"
"image/gif"
"image/jpeg"
"image/png"
"io"
"os"
"golang.org/x/image/bmp"
"golang.org/x/image/webp"
)
type imageDecoder func(io.Reader) (image.Image, error)
var imageDecoders map[string]imageDecoder = map[string]imageDecoder{
`image/jpeg`: jpeg.Decode,
`image/png`: png.Decode,
`image/gif`: gif.Decode,
`image/webp`: webp.Decode,
`image/bmp`: bmp.Decode,
}
func (this *DirectThumbnailer) imageSnapshot(absPath, mimeType string) (image.Image, error) {
// Load file from path
fh, err := os.OpenFile(absPath, os.O_RDONLY, 0400)
if err != nil {
return nil, err
}
defer fh.Close()
// Decode image
fn, ok := imageDecoders[mimeType]
if !ok {
return nil, ErrUnsupportedFiletype
}
return fn(fh)
}