You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
121 lines
3.4 KiB
121 lines
3.4 KiB
// Copyright © 2023 OpenIM. All rights reserved.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package minio
|
|
|
|
import (
|
|
"image"
|
|
_ "image/gif"
|
|
_ "image/jpeg"
|
|
_ "image/png"
|
|
"io"
|
|
|
|
_ "golang.org/x/image/bmp"
|
|
_ "golang.org/x/image/tiff"
|
|
_ "golang.org/x/image/webp"
|
|
)
|
|
|
|
const (
|
|
formatPng = "png"
|
|
formatJpeg = "jpeg"
|
|
formatJpg = "jpg"
|
|
formatGif = "gif"
|
|
)
|
|
|
|
func ImageStat(reader io.Reader) (image.Image, string, error) {
|
|
return image.Decode(reader)
|
|
}
|
|
|
|
func ImageWidthHeight(img image.Image) (int, int) {
|
|
bounds := img.Bounds().Max
|
|
return bounds.X, bounds.Y
|
|
}
|
|
|
|
func resizeImage(img image.Image, maxWidth, maxHeight int) image.Image {
|
|
bounds := img.Bounds()
|
|
imgWidth := bounds.Max.X
|
|
imgHeight := bounds.Max.Y
|
|
|
|
// Calculating scaling
|
|
scaleWidth := float64(maxWidth) / float64(imgWidth)
|
|
scaleHeight := float64(maxHeight) / float64(imgHeight)
|
|
|
|
// If both are 0, then no scaling is done and the original image is returned
|
|
if maxWidth == 0 && maxHeight == 0 {
|
|
return img
|
|
}
|
|
|
|
// If both width and height are greater than 0, select a smaller zoom ratio to maintain the aspect ratio
|
|
if maxWidth > 0 && maxHeight > 0 {
|
|
scale := scaleWidth
|
|
if scaleHeight < scaleWidth {
|
|
scale = scaleHeight
|
|
}
|
|
|
|
// Calculate Thumbnail Size
|
|
thumbnailWidth := int(float64(imgWidth) * scale)
|
|
thumbnailHeight := int(float64(imgHeight) * scale)
|
|
|
|
// Thumbnails are generated using the Resample method of the "image" library.
|
|
thumbnail := image.NewRGBA(image.Rect(0, 0, thumbnailWidth, thumbnailHeight))
|
|
for y := 0; y < thumbnailHeight; y++ {
|
|
for x := 0; x < thumbnailWidth; x++ {
|
|
srcX := int(float64(x) / scale)
|
|
srcY := int(float64(y) / scale)
|
|
thumbnail.Set(x, y, img.At(srcX, srcY))
|
|
}
|
|
}
|
|
|
|
return thumbnail
|
|
}
|
|
|
|
// If only width or height is specified, thumbnails are generated based on the maximum not to exceed rule
|
|
if maxWidth > 0 {
|
|
thumbnailWidth := maxWidth
|
|
thumbnailHeight := int(float64(imgHeight) * scaleWidth)
|
|
|
|
// Thumbnails are generated using the Resample method of the "image" library.
|
|
thumbnail := image.NewRGBA(image.Rect(0, 0, thumbnailWidth, thumbnailHeight))
|
|
for y := 0; y < thumbnailHeight; y++ {
|
|
for x := 0; x < thumbnailWidth; x++ {
|
|
srcX := int(float64(x) / scaleWidth)
|
|
srcY := int(float64(y) / scaleWidth)
|
|
thumbnail.Set(x, y, img.At(srcX, srcY))
|
|
}
|
|
}
|
|
|
|
return thumbnail
|
|
}
|
|
|
|
if maxHeight > 0 {
|
|
thumbnailWidth := int(float64(imgWidth) * scaleHeight)
|
|
thumbnailHeight := maxHeight
|
|
|
|
// Thumbnails are generated using the Resample method of the "image" library.
|
|
thumbnail := image.NewRGBA(image.Rect(0, 0, thumbnailWidth, thumbnailHeight))
|
|
for y := 0; y < thumbnailHeight; y++ {
|
|
for x := 0; x < thumbnailWidth; x++ {
|
|
srcX := int(float64(x) / scaleHeight)
|
|
srcY := int(float64(y) / scaleHeight)
|
|
thumbnail.Set(x, y, img.At(srcX, srcY))
|
|
}
|
|
}
|
|
|
|
return thumbnail
|
|
}
|
|
|
|
// By default, the original image is returned
|
|
return img
|
|
}
|