go-exiftool

go-exiftool

go-exiftool is a golang library that wraps ExifTool.

ExifTool’s purpose is to extract and update as much metadata as possible (EXIF, IPTC, XMP, GPS, …) from a lots of differents file types (Office documents, pictures, movies, PDF, …).

go-exiftool uses ExifTool’s stay_open feature to optimize performance.

Requirements

go-exiftool needs ExifTool to be installed.

• On Debian : sudo apt-get install exiftool

By default, go-exiftool binary will look for exiftool binary in $PATH, but another location can be specified (see SetExiftoolBinaryPath functional option).

Usage

Metadata extraction

et, err := exiftool.NewExiftool()
if err != nil {
    fmt.Printf("Error when intializing: %v\n", err)
    return
}
defer et.Close()

fileInfos := et.ExtractMetadata("testdata/20190404_131804.jpg")

for _, fileInfo := range fileInfos {
    if fileInfo.Err != nil {
        fmt.Printf("Error concerning %v: %v\n", fileInfo.File, fileInfo.Err)
        continue
    }

    for k, v := range fileInfo.Fields {
        fmt.Printf("[%v] %v\n", k, v)
    }
}

Output :

[FOV] 69.4 deg
[Orientation] Rotate 90 CW
[ColorSpace] sRGB
[Compression] JPEG (old-style)
[YCbCrSubSampling] YCbCr4:2:2 (2 1)
[Aperture] 1.7
[ColorComponents] 3
[SubSecCreateDate] 2019:04:04 13:18:03.0937
[FileSize] 26 kB
[FileAccessDate] 2019:05:17 22:44:26+02:00
[DateTimeOriginal] 2019:04:04 13:18:03
[CreateDate] 2019:04:04 13:18:03
(...)

Metadata update

See example function ExampleExiftool_Write in exiftool_sample_test.go

Changelog

• v1.1.0 : initial release
• v1.1.1
  • add typed getters for filemetadata fields
• v1.1.3
  • add Mac & Windows support (thanks to @PROger4ever)
  • increase errors readability (thanks to @PROger4ever)
• v1.2.0
  • add stdout and stderr buffer configuration capabilities (thank to @asannikov)
• v1.3.0
  • Add functionnal option to set ExifTool’s -charset parameter (thank to @PROger4ever)
• v1.3.1
  • fix line separator on macOS
• v1.3.2
  • add Freebsd support (thanks to @ghyman1)
• v1.4.0
  • “NoPrintConversion” functional option (thanks to Kjeldgaard)
• v1.5.0
  • “ExtractEmbedded” functional option
• v1.6.0
  • “ExtractAllBinaryMetadata” functional option
• v1.6.1
  • “SetExiftoolBinaryPath” functional option : specify where to find exiftool binary (default : $path)
• v1.6.2
  • Several improvements (thanks to Dale Hui)
• v1.7.0
  • Add metadata writing capabilities (thanks to Dale Hui)
• v1.8.0
  • Fix a bug that was blocking go-exiftool when a folder was provided. Folder metadata extraction will now return a new sentinel error (ErrNotFile).
  • Add a new sentinel error (ErrBufferTooSmall) that is returned when go-exiftool’s buffer isn’t big enough for a specifi file (countermeasure: initialize go-exiftool with the Buffer option)
  • New option to specify a date format (DateFormat) (thanks to Andy Gorman)
  • New option to output format for GPS coordinates (CoordFormat) (thanks to Andy Gorman)
• v1.9.0
  • New option to specify -api parameter to Exiftool (thanks to Blesmol)
• v1.10.0
  • New option to prefix metadata keys with group names (specifies -G parameter to Exiftool) (thanks to Andy Gorman)