12
\$\begingroup\$

I want to change the Exif data for some .PNG files so that they have the "Date Taken" tag. Is it possible to use that tag on .PNG files?

Is it possible to copy the "Date Modified" date to the "Date Taken" date for then same .PNG file? I'm using ExifTool and I've read in this question that the copying part is possible via exiftool -v "-FileModifyDate>DateTimeOriginal" * but I can't figure out how to use it on the .PNG file.

My questions:

  1. Is it possible to use then "Date Taken" Exif tag on .PNG files?

2.If it is possible, how can I use ExifTool to copy the "Date Modified" tag to the "Date Taken" tag?

Improve this question
\$\endgroup\$

2 Answers 2

Reset to default
10
\$\begingroup\$

What Windows displays under the "Date Taken" property isn't an embedded tag. It fills that property from a number of tags depending upon the file type. For example, for a JPG, Windows will use any of these tags: EXIF:DateTimeOriginal, XMP:DateTimeOriginal, EXIF:CreateDate, and the system FileCreateDate.

ExifTool can create an EXIF:DateTimeOriginal tag in a PNG for you, but Windows doesn't support reading EXIF data in PNGs. Most software doesn't as the EXIF standard in PNG files is only a few years old.

It looks like the tag you want to use is PNG:CreationTime. That shows up in Windows as the "Date Taken" property for me (Win 8.1). So your command would be:
ExifTool "-PNG:CreationTime<FileModifyDate" FILE/DIR

Improve this answer
\$\endgroup\$
1
  • 1
    \$\begingroup\$ Thank you for the help, "ExifTool -v "-PNG:CreationTime<FileModifyDate" -overwrite_original *" solved the problem. \$\endgroup\$
    – Dempa
    Commented Jun 14, 2015 at 10:52
7
\$\begingroup\$

Very recent versions of PNG support EXIF, but a lot of software still does not understand or work with it. The lack of a standardized metadata block has been one of its big disadvantages for photography. If you need a lossless format which preserves (very-similar-to-EXIF, since it's the basis for EXIF) metadata, try TIFF. The downside, though, is that TIFF rendering support is not as widespread as that for PNG (for web applications and other consumer-level display kind of things — for all but the most basic image editing applications, TIFF is everywhere).

Improve this answer
\$\endgroup\$
4
  • \$\begingroup\$ Does TIFF have support for "Date Taken" tag? How can I easily convert all of these .PNG files to .TIFF and preserve the "Date Created" or move it to "Date Taken"? \$\endgroup\$
    – Dempa
    Commented Jun 12, 2015 at 19:39
  • 1
    \$\begingroup\$ @Dempa In Linux, or similar: 1. convert sample.png -compression lzw sample.tif 2. touch --reference=sample.png sample.tif 3. exiftool '-FileModifyDate>DateTimeOriginal' sample.tif \$\endgroup\$
    – mattdm
    Commented Jun 13, 2015 at 1:15
  • \$\begingroup\$ I would qualify that statement about "TIFF rendering support is not as widespread as that for PNG" a little bit... this is very much true if we're talking about web formats, but TIFF has a very long history of support in imaging applications. \$\endgroup\$
    – junkyardsparkle
    Commented Jun 13, 2015 at 3:26
  • \$\begingroup\$ @junkyardsparkle Yeah, good clarification. I've expanded a bit. \$\endgroup\$
    – mattdm
    Commented Jun 13, 2015 at 3:35

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.