Suppose I make a photo and publish it and then find that someone else published it and claimed it's their photo. Or any similar situation - it doesn't matter. So one of the parties of such an argument decides to prove that they were indeed the author of the photo and the other party just unfairly claims authorship.

I heard owning a raw version of the photo is a commonly accepted proof. The author somehow shows that they have a raw version and the other party doesn't have such and so the other party loses the argument. This assumes the author doesn't initially publish the raw photo of course.

What if the photo was taken in JPEG initially? There're many cameras which don't output raw at all - they only output JPEG. Now one person has a JPEG and another person has a JPEG and how do we know who was the author?

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    I can't help but wonder... is this a hypothetical question, or are you actually facing this issue for real?
    – osullic
    Aug 7, 2018 at 11:58
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    This question is inspired by this story pikabu.ru/story/_6075720 in Russian - A claims that B submitted A's photo to a contest under B's name and... won the contest under B's name. I've also read a number of stories where photos are used without permit and sometimes that even turns into a lawsuit.
    – sharptooth
    Aug 7, 2018 at 12:28
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    And so photo.se was flooded with questions about SWIM
    – xiota
    Aug 7, 2018 at 18:28
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    @ToddWilcox, you can't file suit if you haven't registered the copyright, but you can register the copyright after the infringement and still sue. The only restriction that comes from not registering is that, for infringement prior to registration, you can only sue for actual damages, not punitive damages.
    – Mark
    Aug 7, 2018 at 22:05
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    @Mark As long as the copyright is registered within 90 days of first publication, one may still also file for punitive damages (unless the changes effective February 20, 2018 changed that), even if the infringement preceded registration. No one mentioned such a change in the summaries I saw, which mainly dealt with how many images may be included in a single filing and how "single author" is defined for groups of images done by different individuals as work for hire for the same person/entity.
    – Michael C
    Aug 8, 2018 at 8:05

7 Answers 7


Throw away the technology for a second, and consider before digital. Before digital, the negative was defacto proof: there was (typically) only one, and the author had it. But if there was no negative, due to loss or damage, then standard detective/police work is needed: Proof that the photographer was in the location when the shot was taken; testimony of others in the shot or at the location, other photos taken in the same location at same time, etc.

The situation is the same here: you would need additional evidence that the author was at the location at the time of the shot: mobile phone records, GPS, and witnesses. The easiest item is to produce additional photos at the same time and location: the imposter would not have other images.

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    It is no problem to make a copy of a negative. When done correctly, the copy will likely be so good, that it is impossible to distinguish it from the original.
    – jarnbjo
    Aug 7, 2018 at 12:31
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    @jarnbjo - Yes, but I'm guessing that, much as a digital photographer is far more likely to share jpegs than raw, a film photographer is far more likely to share prints than negatives. Hence "there was (typically) only one".
    – AndyT
    Aug 7, 2018 at 13:33
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    If both the original negative and copy are available, I would expect an expert/scientist to be able to distinguish which was which.
    – dav1dsm1th
    Aug 7, 2018 at 16:09
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    @jarnbjo The copy negative can never contain information that an original does not. The obverse is not true. It is almost always possible to forensically determine which of two negatives is the one from which the other was sourced, either directly or indirectly via an intermediate print.
    – Michael C
    Aug 7, 2018 at 19:48
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    Film cameras almost always left a pattern scratch marks on the negative that were characteristic of the particular camera, even if the marks were too small to regrade the print quality. If it's admissible legal evidence to match a bullet to the gun it was shot from, the same applies to film and cameras. A copy of the negative would not preserve those "fingerprints".
    – alephzero
    Aug 7, 2018 at 23:12

You can prove that the picture is yours if you have other data that are not in the subject picture:

  • the RAW file from which the JPEG can be produced (framing/perspective)
  • a higher-definition picture from which the subject JPEG has been scaled down
  • a larger picture (at the same definition) from which the subject JPEG has been cropped or some details removed (for instance, that phone pole which is there IRL)
  • a series of pictures taken at the same time and place from which the subject picture is extracted
  • all of the above :)

Basically, never post all the pixels of the shot...

  • Good points, except for your first one which is explicitly ruled out by the OP.
    – Robin
    Aug 7, 2018 at 14:54
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    Yes, but I wanted the answer to be complete.
    – xenoid
    Aug 7, 2018 at 17:29
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    Not sure about the conclusion: arguably, the cropped picture may (should?) be better than the uncropped one
    – clabacchio
    Aug 8, 2018 at 7:24
  • @clabacchio But if one party can produced an uncropped image and the other party can only produce the cropped version that was published by the first party...
    – Michael C
    Aug 9, 2018 at 2:45

There are several possibilities, and the hierarchy will vary from one place to the next.

But in general, the idea of precedence is the starting point. That is, who published the image first? Absent of any other compelling evidence to the contrary, the person who first published the image will probably be recognized as the author of the image.

Things that could possibly override the earliest original publication date:

  • If one party can produce a higher resolution version of the image than the other (that does not appear to only be an up-scaled version of the information contained in the smaller sized version), or any other more pristine version of the image. For instance, a less compressed version of the image at the same resolution would carry similar weight as a higher resolution version would.
  • Copyright information in the metadata of both images that agrees that the same person is the author of both images. Almost all major publications require the IPTC metadata in an image to include copyright owner/author information.¹
  • A camera or lens serial number in the metadata of both published images that matches a camera or lens to which one but not the other had access.¹
  • Any other details in both copies of the image or its metadata that can establish a specific camera produced the image if only one of the two persons claiming to have the produced the image had access to that specific camera.²
  • Corroborating evidence that one but not the other person was present at the time and place the image was captured. If the image is from a specific event and one person was issued a media pass that placed them in the position to have captured the shot from a "press only" area while the other person can not demonstrate they were present at the event then the person who can demonstrate that they were there probably prevails. This would be particularly the case if everyone who had access to the place from which the image was recorded required documentation/registration/media pass/etc.
  • The testimony/deposition of any persons pictured in the photo, or person(s) who witnessed the photo being taken, as to who took the photo.

¹ Please notice that all references to metadata as valid for determining authorship is placed in the context of both versions of the image as published by both parties having the same metadata content for the particular fields in question. It would also be based upon the premise that the actual image information can be shown to have been produced by the camera indicated in the metadata. If the metadata does not agree, then it would behoove both parties to make their case based on other factors, or to establish that their version of the metadata is the original version using whatever forensic methods they may have at their disposal. Please see note 2 below for more regarding congruence between image information and metadata.
The question seems to demonstrate no awareness that such information can even exist within the image file itself. It therefore seems possible that a party who violates someone else's copyright might also be unaware of such metadata and publish the image as their own without altering the metadata. In such a case, establishment of ownership would likely be resolved long before going to trial.
² For instance, if the content of the actual image data does not match those used by the camera indicated in the metadata, that would raise a red flag that the metadata has, in fact, been altered. It could be one or more of any number of things: Does the compression algorithm used, or the pixel mapping used to map out hot pixels, or other sensor characteristics revealed by the actual image data, match the camera referenced in the camera information fields of the metadata? Is the serial number in the metadata a valid serial number for the type of camera that took the image? Can the camera indicated in the metadata have been used to produce the image in question, or is there some characteristic of the actual image contents that eliminates any possibly doctored metadata, such as camera identifying EXIF fields, from being valid?

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    I sincerely hope that image metadata is not considered proof of anything by a court. Any child can take one of your image files and insert metadata with my equipment's serial numbers.
    – jarnbjo
    Aug 7, 2018 at 10:53
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    @jarnbjo I have absolutely no clue about legal things, but I suppose it would be up to your legal representative to explain that to the court.
    – osullic
    Aug 7, 2018 at 11:57
  • @jarnbjo first of all, the internet is not the place for anyone to obtain legal "definitives". Now, isn't it the case that courts listen to evidence and make judgements? So, legal representative A uses metadata as "evidence" of something. Legal representative B refutes that metadata proves anything. That's how I see it working. I'm certainly not arguing with you - as I plainly said, I have no expertise in this area - but I will certainly repeat that the internet is not the place for anyone to be getting answers to questions of law.
    – osullic
    Aug 7, 2018 at 14:23
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    @jarnbjo, so in that case why post it as a comment to this answer, which specifically and repeatedly talks about commonalities between the metadata of both images? Aug 7, 2018 at 16:00
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    For those who are overly concerned about the metadata, while it is easy to alter (exiftool -SerialNumber="0000" image.jpg), you need multiple lines of evidence to prove something. You cannot hang your hat on just one thing. That is why the answer currently has 4 paragraphs and 6 bullet points. All available information has to be considered.
    – xiota
    Aug 8, 2018 at 8:15

It might also be worth noting that cameras have a specific signatures in the form of the noise pattern which apparently is worth, here is one article talking about this:

Hidden “Signature” in Online Photos Could Help Nab Child Abusers
A new technique exploits sensor noise patterns unique to each camera that can help identify criminals via photographs posted online

The article talks about how this could be used for forensics, but maybe for this purpose here as well, especially if we are talking about multiple photos.


Steganography (messages hidden in plain sight) can prevent this situation

A steganographic watermark can be used on digital images to hide a message within the image. This would allow an author to put a secret ownership message within the image itself without altering the image's colors enough to be seen by the naked eye.

enter image description here (https://www.endgame.com/blog/technical-blog/instegogram-leveraging-instagram-c2-image-steganography)

Even if a person were to screenshot the image from the web or download it and spoof the EXIF data, the secret message can be extracted. You can place in a message into the image saying "Copyright Sharptooth" in random spots. If there is ever question to who owns the image, you can extract the steganographic message and reveal that you are the owner.

For more information on how image Steganography works, check out this video by Computerphile: https://www.youtube.com/watch?v=TWEXCYQKyDc

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    Ordinary people call this digital watermarking. People being watched by certain government agencies call it stegosaurusy. Also, depending on methods used, it's unlikely that it would survive through even JPEG rounding errors intact.
    – xiota
    Aug 8, 2018 at 1:56
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    @xiota: if someone recompresses the image, it will necessarily lose at least a little quality. That's normally detectable (see other answer), so you can either prove that you have a higher-quality copy of the image than the other person making a claim, or their copy is bit-exact or high-enough quality to preserve the steganography. Hiding a small message over a whole image can (I think) be done fairly robustly, in ways that will survive recompression at any nearly-transparent quality level. Aug 8, 2018 at 4:11
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    @PeterCordes My comment is specifically about stegasaurus-watermarking. The naive approach is to modify the least significant bits of an image. This would not survive JPEG compression, even at 100%. A JPEG-specific approach, such as modifying the quantization coefficients, would also not survive JPEG-recompression, and it certainly wouldn't survive a screenshot. Stegasauruses aren't particularly robust. That's why they're extinct.
    – xiota
    Aug 8, 2018 at 5:41
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    @xiota A good watermarking algorithm is designed to withstand compression. Hiding the message in the LSB is not good watermarking. It is true however that, as always in information security, the method depends on your threat model. Aug 8, 2018 at 10:34
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    Steganography refers to messages hidden in the medium with the purpose of concealing their presence. What you're talking about is indeed called watermarking. Of course you could use steganography for the purpose of watermarking, but it would be suboptimal. Aug 8, 2018 at 11:43

Time stamps of each image would be one way. Obviously, if you posted your image first, it's timestamp would be earlier than the stolen copy.

EXIF data. In many cameras, you have the ability to add copyright information right into the EXIF data. Plus, if you have the original, then your image will have all of the EXIF data. Images uploaded to the web are commonly stripped of their EXIF data in whole or in part. Some cameras will write the model & serial number of the image. GPS information could allow one to prove that the alleged perpetrator couldn't have taken the shot since they were never in the specified location.

Image Size: If you upload lower-resolution images, then only you will have the full-resolution image while the person who uploaded the stolen copy can't.

There are apps that will embed copyright data right into the image itself which is impossible to remove.

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    Timestamp where? If the timestamp is part of any data hosted by your website, then you have control over it, and so it is not reliable. I suppose if your website is archived by another website, then that website's timestamp would be admissible evidence. Aug 7, 2018 at 19:57
  • GPS isn't useful here. If one of the contenders has really taken the picture, s/he knows where this was, and can prove it with shots from other folks (or Google's StreetView....) if it was taken outdoors or in a public building.
    – xenoid
    Aug 7, 2018 at 23:50
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    AFAIK EXIF doesn't have a proper digital signature of the photo, so I could take a photo similar to yours, rip the EXIF from it and attach to your photo. Aug 8, 2018 at 11:31
  • Accumulation - The timestamp is embedded within the file's metadata.
    – Frank
    Aug 8, 2018 at 21:29
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    @DmitryGrigoryev That is correct. But you don't even need to "rip" something from anything, because EXIF data is trivial to edit. There is lots of software to do that and it doesn't leave any traces in the file. So EXIF data does not prove anything. I would downvote this answer, but I don't have the necessary reputation on this site.
    – Philipp
    Aug 9, 2018 at 8:28

Having the original in JPEG is not that different from having it in RAW.

If the author published the original JPEG straight from the camera, they will need proof besides the original image to prove authorship. Typically the author would have other shots of the subject/event that they didn't publish. It's also possible to prove that the shot was taken by a particular camera (by analysing the sensor defects which result in similar artefacts in other photos). If the author owned the camera, they would have no problem presenting other shots they have done with it.

If the author processed the original shot before publishing, they could prove authorship by releasing the original shot together with instructions on how to process it. Generating a fake unprocessed shot in JPEG isn't any easier than generating a fake unprocessed shot in RAW.

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