Does heavily editing someone else’s photo avoid copyright infringement?

No. Heavily editing someone else’s photo does not automatically remove copyright protection.

In general, copyright covers the original work and also gives the copyright owner control over adaptations or “derivative works.” That means cropping, retouching, compositing, recoloring, or otherwise altering an image usually still requires permission from the copyright holder.

The idea that changing an image “enough” makes it free to use is a myth. The legal line is not based on a simple percentage of change.

There are limited exceptions in some countries, such as fair use/fair dealing, but editing by itself is not what creates that exception. Whether an unlicensed use is lawful depends on specific legal factors and, if disputed, ultimately a court decision.

A safer rule: if the image was created by someone else, assume you need permission unless the photo is clearly licensed for your use, in the public domain, or your use clearly falls under a legal exception.