Copyright of a white pixel
<p>We had a theoretical discussion on copyright and couldn't agree on an answer.</p>
<p>Please keep in mind that we purposely ignored common sense and were just thinking about the hard legal implications.</p>
<p>Say there is a copyrighted picture. Making a copy of that picture falls under the protection of the copyright, even if it is not a perfect copy, even if the quality of the copy is significantly worse than the original.</p>
<p>Is there a limit to this?</p>
<p>Or in other words, if I reduce the color resolution of the copy to 1 bit (meaning, only black or white are possible) and the spacial resolution to one square pixel, is this still a copy of the original for the purposes of copyright?</p>
<p>If so, isn't a white pixel a copyrighted version of half of the world's copyrighted content?</p>
<p>If not, where is the limit where copyright vanishes?</p>

<p>US law simply prohibits copying, not possession of a pixel. If you copy 90% of a work, you are still copying, infringing on the creators exclusive right. Same is true if you copy 20%, and so on. The pertinent first question is, how do the courts decide if there has been copying? This is a factual matter decided on the basis of preponderance of evidence. Defense will argue, very persuasively, that it is more likely that the presence of an identical pixel in two works is purely coincidental (likewise, the appearance of the word &quot;is&quot; in two texts is purely coincidental&quot;). We <em>can</em> imagine future technology with megabyte pixels, where the particular &quot;white&quot; pixel is unique to the original work, and no reasonable fact-finder could hold that the later word accidentally stumbled onto exactly that pixel.</p>
<p>The second thing that has to be established is that the degree of copying &quot;matters&quot;, starting with <a href="https://en.wikipedia.org/wiki/Perris_v._Hexamer" rel="noreferrer">Perris  v.  Hexamer</a>, so that to be infringing, the degree of copying must be more than minimal.
Courts have long relied on the notion of <a href="https://repository.law.umich.edu/cgi/viewcontent.cgi?article=1060&amp;context=mbelr" rel="noreferrer">&quot;substantial similarity&quot;</a>, where you know it when you see it, that is, ordinary observation would cause it to be recognized as having been taken from another work. There is no bright line drawn by Congress of SCOTUS regarding how much copying is &quot;material&quot;. It is extremely unlikely that a reasonable line could be drawn that would render single-pixel copying &quot;material&quot;.</p>

<p>The law is not mathematics. There is no exact number of pixels which is a minimum. You cannot say that 1 pixel is exempt from copyright, that N+1 pixels are free from copyright when N pixels are free from copyright, and that therefore all images are free from copyright.</p>
<p>Lawsuits deal with actual cases, so this is not a practical problem for the use of copyright law. At stake won't be a theoretical image with an abstract number N of pixels. There will be a specific image, and that will not be an image with 1 pixel.</p>

copyright