Functions

Warning

It could set any value in exif without actual value. For example, actual XResolution is 300, whereas XResolution value in exif is 0. Confliction might happen.

Warning

To edit exif tags and values appropriately, read official document from P167-. http://www.cipa.jp/std/documents/e/DC-008-2012_E.pdf

load

piexif.load(jpegData)

Get exif data as object. jpegData must be a string that starts with “data:image/jpeg;base64,”(DataURL), “\xff\xd8”, or “Exif”.

Arguments:
  • jpegData (string) – JPEG data
Returns:

Exif data({“0th”:object, “Exif”:object, “GPS”:object, “Interop”:object, “1st”:object, “thumbnail”:string})

Return type:

object

var exifObj = piexif.load(jpegData);
for (var ifd in exifObj) {
    if (ifd == "thumbnail") {
        continue;
    }
    console.log("-" + ifd);
    for (var tag in exifObj[ifd]) {
        console.log("  " + piexif.TAGS[ifd][tag]["name"] + ":" + exifObj[ifd][tag]);
    }
}

dump

piexif.dump(exifObj)

Get exif binary as string to insert into JPEG.

Arguments:
  • exifObj (object) – Exif data({“0th”:0thIFD - object, “Exif”:ExifIFD - object, “GPS”:GPSIFD - object, “Interop”:InteroperabilityIFD - object, “1st”:1stIFD - object, “thumbnail”:JPEG data - string})
Returns:

Exif binary

Return type:

string

var zeroth = {};
var exif = {};
var gps = {};
zeroth[piexif.ImageIFD.Make] = "Make";
zeroth[piexif.ImageIFD.XResolution] = [777, 1];
zeroth[piexif.ImageIFD.YResolution] = [777, 1];
zeroth[piexif.ImageIFD.Software] = "Piexifjs";
exif[piexif.ExifIFD.DateTimeOriginal] = "2010:10:10 10:10:10";
exif[piexif.ExifIFD.LensMake] = "LensMake";
exif[piexif.ExifIFD.Sharpness] = 777;
exif[piexif.ExifIFD.LensSpecification] = [[1, 1], [1, 1], [1, 1], [1, 1]];
gps[piexif.GPSIFD.GPSVersionID] = [7, 7, 7, 7];
gps[piexif.GPSIFD.GPSDateStamp] = "1999:99:99 99:99:99";
var exifObj = {"0th":zeroth, "Exif":exif, "GPS":gps};
var exifbytes = piexif.dump(exifObj);

Properties of piexif.ImageIFD help to make 0thIFD and 1stIFD. piexif.ExifIFD is for ExifIFD. piexif.GPSIFD is for GPSIFD. piexif.InteropIFD is for InteroperabilityIFD.

Note

ExifTag(34665), GPSTag(34853), and InteroperabilityTag(40965) in 0thIFD automatically are set appropriate value.

Note

JPEGInterchangeFormat(513), and JPEGInterchangeFormatLength(514) in 1stIFD automatically are set appropriate value.

Note

If ‘thumbnail’ is contained in exifObj, ‘1st’ must be contained – and vice versa. 1stIFD means thumbnail’s information.

insert

piexif.insert(exifbytes, jpegData)

Insert exif into JPEG.

Arguments:
  • exifbytes (string) – Exif binary
  • jpegData (string) – JPEG data
Returns:

JPEG data

Return type:

string

var exifbytes = piexif.dump(exifObj)
var newJpeg = piexif.insert(exifbytes, jpegData)

remove

piexif.remove(jpegData)

Remove exif from JPEG.

Arguments:
  • jpegData (string) – JPEG data
Returns:

JPEG data

Return type:

string

var newJpeg = piexif.remove("foo.jpg")