Also matching by root mean squared error is pretty specific. It is possible to match based on other error criteria.
I see your point now, although I do not see the original person (@tomcam) explicitly saying 'patents prevented photomosaics'. I only see "Fun to see it commoditized like this." [1]
>> Also matching by root mean squared error is pretty specific. It is possible to match based on other error criteria.
The applicability of the said patent [2] is not limited to use of RMS error. I do not see "root mean square" anywehere in Claim 1 or any independent claim of the patent. That is introduced only in dependent claims like claim 3.
In case you do not already, you may consider reading [3-5] below to understand how coverage of a patent depends on independent and dependent claims.
[1] https://news.ycombinator.com/item?id=27532662
[2] https://worldwide.espacenet.com/patent/search/family/0267124...
[3] https://en.wikipedia.org/wiki/Patent_application#Claims
[4] https://en.wikipedia.org/wiki/Patent_claim
[5] https://en.wikipedia.org/wiki/Patent_claim#Basic_types_and_c...
"A mosaic image is formed from a database of source images. More particularly, the source images are analyzed, selected and organized to produce the mosaic image. A target image is divided into tile regions, each of which is compared with individual source image portions to determine the best available matching source image by computing red, green and blue channel root-mean square error. The mosaic image is formed by positioning the respective best-matching source images at the respective tile regions."
Please take a look at the claims I have cited in this comment chain, and also read about the importance and relevance of the claims from the links I recommended.
When reading a patent to understand what it covers or not, it's recommended to start with the independent claims.
Hope this helps. :-)
