没有人有使用“ github.com/gohugoio/hugo/resources/images/exif”使用Go从本地图像中提取元数据的示例吗?
我浏览了文档,由于我是Go语言的新手,所以我不确定100%是否正在写东西。我确实读过图像,但不确定下一步将是什么。
fname := "image.jpg"
f, err := os.Open(fname)
if err != nil {
log.Fatal("Error: ", err)
}
(编辑1)实际上,我认为我找到了解决方案:
d, err := exif.NewDecoder(exif.IncludeFields("File Type"))
x, err := d.Decode(f)
if err != nil {
log.Fatal("Error: ", err)
}
fmt.Println(x)
但是,问题是我如何知道哪些字段可用?例如,File Type
返回<nil>
看起来像雨果使用github.com/rwcarlsen/goexif。
go.dev上的软件包文档显示Exif.Walk可以遍历每个非nil EXIF字段的名称和标记。
例如,一个小程序:
package main
import (
"fmt"
"log"
"os"
"github.com/rwcarlsen/goexif/exif"
"github.com/rwcarlsen/goexif/tiff"
)
type Printer struct{}
func (p Printer) Walk(name exif.FieldName, tag *tiff.Tag) error {
fmt.Printf("%40s: %s\n", name, tag)
return nil
}
func main() {
if len(os.Args) < 2 {
log.Fatal("please give filename as argument")
}
fname := os.Args[1]
f, err := os.Open(fname)
if err != nil {
log.Fatal(err)
}
x, err := exif.Decode(f)
if err != nil {
log.Fatal(err)
}
var p Printer
x.Walk(p)
}
示例:
$ go run main.go IMG_123.JPG
ResolutionUnit: 2
YCbCrPositioning: 2
Make: "Canon"
Model: "Canon IXUS 255 HS"
ThumbJPEGInterchangeFormat: 5620
PixelYDimension: 3000
FocalPlaneResolutionUnit: 2
GPSVersionID: [2,3,0,0]
ExifVersion: "0230"
WhiteBalance: 1
DateTime: "2016:10:04 17:27:56"
CompressedBitsPerPixel: "5/1"
... etc ...
Orientation: 1
MeteringMode: 5
FocalLength: "4300/1000"
PixelXDimension: 4000
InteroperabilityIFDPointer: 4982
FocalPlaneXResolution: "4000000/244"
XResolution: "180/1"
ComponentsConfiguration: ""
ShutterSpeedValue: "96/32"
ApertureValue: "101/32"
ExposureBiasValue: "-1/3"
FocalPlaneYResolution: "3000000/183"
SceneCaptureType: 0