79 lines
2.2 KiB
Go
79 lines
2.2 KiB
Go
/*
|
|
|
|
Package thumb provides JPEG resampling and thumbnail generation.
|
|
|
|
Copyright (c) 2018 - 2022 PhotoPrism UG. All rights reserved.
|
|
|
|
This program is free software: you can redistribute it and/or modify
|
|
it under Version 3 of the GNU Affero General Public License (the "AGPL"):
|
|
<https://docs.photoprism.app/license/agpl>
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU Affero General Public License for more details.
|
|
|
|
The AGPL is supplemented by our Trademark and Brand Guidelines,
|
|
which describe how our Brand Assets may be used:
|
|
<https://photoprism.app/trademark>
|
|
|
|
Feel free to send an email to hello@photoprism.app if you have questions,
|
|
want to support our work, or just want to say hello.
|
|
|
|
Additional information can be found in our Developer Guide:
|
|
<https://docs.photoprism.app/developer-guide/>
|
|
|
|
*/
|
|
package thumb
|
|
|
|
import (
|
|
"fmt"
|
|
"math"
|
|
|
|
_ "image/gif"
|
|
_ "image/jpeg"
|
|
_ "image/png"
|
|
|
|
_ "golang.org/x/image/bmp"
|
|
_ "golang.org/x/image/tiff"
|
|
_ "golang.org/x/image/webp"
|
|
|
|
"github.com/photoprism/photoprism/internal/event"
|
|
)
|
|
|
|
var log = event.Log
|
|
|
|
// Url returns a thumbnail url based on hash, thumb name, cdn uri, and preview token.
|
|
func Url(h, name, contentUri, previewToken string) string {
|
|
return fmt.Sprintf("%s/t/%s/%s/%s", contentUri, h, previewToken, name)
|
|
}
|
|
|
|
// Thumb represents a photo thumbnail.
|
|
type Thumb struct {
|
|
W int `json:"w"`
|
|
H int `json:"h"`
|
|
Src string `json:"src"`
|
|
}
|
|
|
|
// New creates a new photo thumbnail.
|
|
func New(w, h int, hash string, s Size, contentUri, previewToken string) Thumb {
|
|
if s.Width >= w && s.Height >= h {
|
|
// Smaller
|
|
return Thumb{W: w, H: h, Src: Url(hash, s.Name.String(), contentUri, previewToken)}
|
|
}
|
|
|
|
srcAspectRatio := float64(w) / float64(h)
|
|
maxAspectRatio := float64(s.Width) / float64(s.Height)
|
|
|
|
var newW, newH int
|
|
|
|
if srcAspectRatio > maxAspectRatio {
|
|
newW = s.Width
|
|
newH = int(math.Round(float64(newW) / srcAspectRatio))
|
|
} else {
|
|
newH = s.Height
|
|
newW = int(math.Round(float64(newH) * srcAspectRatio))
|
|
}
|
|
|
|
return Thumb{W: newW, H: newH, Src: Url(hash, s.Name.String(), contentUri, previewToken)}
|
|
}
|