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Does any picture file format embed author, title etc.? I'm currently playing with ffmpeg and such info ships with a video file and I thought it useful. I was wondering if an image file can also pack these attributes.

I realise if they did exist they'd probably be easily changed and so won't protect intellectual property rights. Nevertheless, I think it is a good feature.

I also realise that Windows has extended file properties but I was hoping for something embedded in the file itself rather than the O.S. file descriptor (which I presume is how windows does this).

  • Any metadata that is specific to a genre of file types (e.g., images, audio or video) is stored in the file.  So, when a file has metadata like title, artist, composer, author, dimensions, date taken, etc., those are stored in the file.  The OS keeps track only of universal things like file name, owner, file system attributes (e.g., read-only or hidden), file size, date modified, etc.  (But Windows Explorer does understand how to read, and in many cases modify, metadata fields in common file types; e.g., JPEG.) – Scott Jul 22 at 19:59
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Exif can contain metadata about title, author, etc

Exif (Exchangeable image file format) can contain authorship, copyright information:

The metadata tags defined in the Exif standard cover a broad spectrum:

  • Date and time information
  • Descriptions
  • Copyright information

Exif metadata can be present in JPEG images, for example. There is a complete listing of Exif tags which is too long to include here, but you are probably interested in the ImageDescription, Artist (or XPAuthor) tags.

Alternatively, XMP (Extensible Metadata Platform) provides a standard for embedding metadata in a file in the form of XML including multiple image formats.

PNG images use a different format, but can also contain metadata:

PNG provides the tEXt, iTXt, and zTXt chunks for storing text strings associated with the image, such as an image description or copyright notice. Keywords are used to indicate what each text string represents. Any number of such text chunks may appear, and more than one with the same keyword is permitted.

GIF files can include metadata in a comment block (thanks A C for pointing that out) as standard. They could also include information in plain text or application-extension blocks.

For vector image files, SVGs are XML and so can include metadata via the <metadata>, <title> and <desc> elements. (thanks A C for reminding me about SVGs)

Many of these metadata listings will conform to the Dublin Core schema/vocabulary, which gives standardised naming for each of the elements, eg 'Contributor', 'Creator', 'Date', etc.

Other means of including data in image files

As pointed out in the comments, there are other ways of including metadata in image files. I would point out that these are not necessarily part of an official file format or specification, however.

Steganography is the method of concealing a message within a message. This is a general technique and not limited to image files; it can also be done in video files, audio files, even in a physical medium.

There are images given as examples, such as:

tree with steganographysteganographic image

(credit to Cyp on English Wikipedia for both images)

Additionally, a signature and date could be added to the image to embed author and creation time, for example.

Of course, all of these examples affect the actual image data itself, to a greater or lesser extent, unlike extra information contained in tags or fields.

  • Any image format can contain such data, but it might not easily be readable (think steganography) :) – DavidPostill Jul 21 at 14:26
  • @DavidPostill Or easily: a signature in the corner. :) – Kamil Maciorowski Jul 21 at 19:29
  • Cute point, @DavidPostill - you can take a picture of your business card and say that the image contains author info as well. I think it's important for OP's understanding to distinguish extra data which does not affect the image data vs steganography or watermarks. To be clear, while you're talking about the latter, bertieb is talking about the former. It might also be worth mentioning that GIF files can include comments, SVGs can include a bunch of stuff - the ability to embed extra information is present in most common image formats. (And OP is right: it is editable and won't protect IP) – A C Jul 21 at 20:28

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