photoprism/internal/thumb/create.go

143 lines
3.7 KiB
Go

package thumb
import (
"errors"
"fmt"
"image"
"image/png"
"os"
"path"
"path/filepath"
"github.com/disintegration/imaging"
"github.com/photoprism/photoprism/pkg/fs"
"github.com/photoprism/photoprism/pkg/sanitize"
)
// Suffix returns the thumb cache file suffix.
func Suffix(width, height int, opts ...ResampleOption) (result string) {
method, _, format := ResampleOptions(opts...)
result = fmt.Sprintf("%dx%d_%s.%s", width, height, ResampleMethods[method], format)
return result
}
// FileName returns the thumb cache file name based on path, size, and options.
func FileName(hash string, thumbPath string, width, height int, opts ...ResampleOption) (fileName string, err error) {
if InvalidSize(width) {
return "", fmt.Errorf("resample: width exceeds limit (%d)", width)
}
if InvalidSize(height) {
return "", fmt.Errorf("resample: height exceeds limit (%d)", height)
}
if len(hash) < 4 {
return "", fmt.Errorf("resample: file hash is empty or too short (%s)", sanitize.Log(hash))
}
if len(thumbPath) == 0 {
return "", errors.New("resample: folder is empty")
}
suffix := Suffix(width, height, opts...)
p := path.Join(thumbPath, hash[0:1], hash[1:2], hash[2:3])
if err := os.MkdirAll(p, os.ModePerm); err != nil {
return "", err
}
fileName = fmt.Sprintf("%s/%s_%s", p, hash, suffix)
return fileName, nil
}
// FromCache returns the thumb cache file name for an image.
func FromCache(imageFilename, hash, thumbPath string, width, height int, opts ...ResampleOption) (fileName string, err error) {
if len(hash) < 4 {
return "", fmt.Errorf("resample: invalid file hash %s", sanitize.Log(hash))
}
if len(imageFilename) < 4 {
return "", fmt.Errorf("resample: invalid file name %s", sanitize.Log(imageFilename))
}
fileName, err = FileName(hash, thumbPath, width, height, opts...)
if err != nil {
log.Error(err)
return "", err
}
if fs.FileExists(fileName) {
return fileName, nil
}
return "", ErrThumbNotCached
}
// FromFile returns the thumb cache file name for an image, and creates it if needed.
func FromFile(imageFilename, hash, thumbPath string, width, height, orientation int, opts ...ResampleOption) (fileName string, err error) {
if fileName, err := FromCache(imageFilename, hash, thumbPath, width, height, opts...); err == nil {
return fileName, err
} else if err != ErrThumbNotCached {
return "", err
}
// Generate thumb cache filename.
fileName, err = FileName(hash, thumbPath, width, height, opts...)
if err != nil {
log.Error(err)
return "", err
}
// Load image from storage.
img, err := Open(imageFilename, orientation)
if err != nil {
log.Error(err)
return "", err
}
// Create thumb from image.
if _, err := Create(img, fileName, width, height, opts...); err != nil {
return "", err
}
return fileName, nil
}
// Create creates an image thumbnail.
func Create(img image.Image, fileName string, width, height int, opts ...ResampleOption) (result image.Image, err error) {
if InvalidSize(width) {
return img, fmt.Errorf("resample: width has an invalid value (%d)", width)
}
if InvalidSize(height) {
return img, fmt.Errorf("resample: height has an invalid value (%d)", height)
}
result = Resample(img, width, height, opts...)
var saveOption imaging.EncodeOption
if filepath.Ext(fileName) == "."+string(fs.FormatPng) {
saveOption = imaging.PNGCompressionLevel(png.DefaultCompression)
} else if width <= 150 && height <= 150 {
saveOption = imaging.JPEGQuality(JpegQualitySmall)
} else {
saveOption = imaging.JPEGQuality(JpegQuality)
}
err = imaging.Save(result, fileName, saveOption)
if err != nil {
log.Errorf("resample: failed to save %s", sanitize.Log(filepath.Base(fileName)))
return result, err
}
return result, nil
}