x265 Licensing FAQ

Who owns x265?

MulticoreWare is the primary developer of x265.  MulticoreWare owns the copyright to x265 and the x265 trademark.  All portions of x265 are either works of original authorship of MulticoreWare, contributions from developers who have signed a Contributor Agreement, or were otherwise fully licensed with all necessary rights by MulticoreWare.

How is x265 licensed?

x265 is made available under the open source GNU GPL v2 license, to anyone who is willing to comply with the terms of this license.  x265 is also offered by MulticoreWare under Commercial License Agreements.

Can I use x265 in my open-source product?

If your open source product is offered under and compliant with the GPL v2, the answer is yes:  you can incorporate and distribute the combined work in full compliance with x265’s GPL v2 license.  You can build and distribute products under even more permissive open source licenses like the BSD modified or Apache license, but you must keep the x265 library as a separate library, distributed under the GPL v2.  You cannot cause x265 to become available under another open source license.

Can I use x265 in my commercial product?

If you have a commercial license, yes, you can incorporate x265 and distribute commercial products under the terms of that license.  Commercial licensees are not subject to the terms of the GPL v2 (for example, the requirement to offer your product under the GPL v2 and make the source code of your application available to anyone who requests it).  If you do not have a commercial license for x265 from MulticoreWare, the answer is no, unless your commercial product is distributed under the GPL v2 license.

If I use x265 in my product, will I be required to disclose my source code?

If you don’t have a commercial license, and you incorporate x265 offered under the GPL v2 license into your product, your product will be subject to the terms of the GPL v2 license.  Thus, you must make the source code to your product available to any user upon request.  If you have a commercial license, you will be able to keep your product’s source code proprietary.

What are the benefits of taking a commercial license to x265?

  • A commercial license allows you to distribute proprietary applications without being subject to the copyleft terms and other terms of the GPL v2.
  • A commercial license allows you to tightly integrate x265 into your application, optimizing performance and assuring your customers of a complete, tested solution.
  • Commercial licensees are supported directly by MulticoreWare’s x265 development team, with contractual commitments.
  • Commercial licensees have a say in the x265 product roadmap.  Features are prioritized based on feedback from commercial customers.
  • x265 is the first name in HEVC encoding.  Commercial licensees have the right to use the x265 logo and brand in their marketing.

Are commercial licensees required to contribute their modifications back to the x265 project?

Commercial licensees are granted the right to make modifications to x265, but they can only distribute the modified version of x265 if they contribute their modifications back to the x265 project.

If I use x265, obtained under the GNU GPL v2, am I allowed to modify the original code into a new program, then distribute and sell that new program commercially?

If you use x265 under the GPL v2 license you are allowed to sell copies of the modified program commercially, but only under the terms of the GNU GPL v2.  You must make the source code available to the users of the program as described in the GPL, and they must be allowed to redistribute and modify it as described in the GPL.  These requirements are the condition for including the GPL-covered code you received in a program of your own.

Can I add support for x265 to my product, encouraging my end-users to download the GPL version of x265 and plug it in on their own?

We don’t regard this attempted “workaround” to the conditions imposed by the GPL v2 to be any different than distributing x265 in your product directly.  See https://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.en.html#LinkingWithGPL

This is also a really bad idea for a commercial product, as end customers wouldn’t get a fully integrated, tested, supported solution.  Your commercial product would break often, and it would not perform nearly as well as competing products that have licensed x265 commercially.

Instead of using x265 (GPL v2), can I use FFMPEG or VLC (LGPL) with x265 in my commercial product?

Although FFMPEG and VLC are offered under the LGPL license, when compiled with x265 they are subject to the GPL v2 license.  If you use FFMPEG or VLC compiled with x265 in your commercial product it will be subject to the terms of the GPL v2.

To avoid causing my commercial product to be subject to the terms of the GPL v2, can I create or use a “wrapper” application or API, where the wrapper is offered under the LGPL?

An LGPL API or application cannot use GPL v2 software and still comply with the LGPL.  Doing this causes the wrapper application or API to be subject to the terms of the GPL v2.  If you would like to add x265 to your commercial application, your product will be subject to the terms of the GPL v2 open source license unless you get a commercial license from MulticoreWare.

Aren’t there exceptions to that would allow me to use x265 GPL v2 in my commercial application if I don’t do “deep integration” (for example, if I only pass a command-line to libx265, feeding frames in through pipes)?

Given the nature of what x265 does when used with any video related product, we don’t believe that this is possible.  See https://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.en.html#GPLInProprietarySystem.  “You cannot incorporate GPL-covered software in a proprietary system.  A system incorporating a GPL-covered program is an extended version of that program. The GPL says that any extended version of the program must be released under the GPL if it is released at all.”

Are there exceptions for dynamic linking instead of static linking x265?

No. Linking a GPL covered work statically or dynamically with other modules is making a combined work based on the GPL covered work. Thus, the terms and conditions of the GNU General Public License cover the whole combination.  See https://www.gnu.org/licenses/gpl-faq.html#GPLStaticVsDynamic

Isn’t MulticoreWare subject to the terms of the GPL v2?

No.  MulticoreWare owns x265.  MulticoreWare is the licensor, not the licensee.  However, MulticoreWare has made a commitments to the x264 developers that x265 will always be available under the GPL v2, and that there will be no private forks of x265.

What does a commercial license cost?

As we are in a competitive market, we don’t list our pricing and license terms publicly.  Our commercial licensees tell us that the terms are very competitive with proprietary codecs.  If you are a commercial company interested in adding x265 to your product or service, write to us at sales @ multicorewareinc.com.  We will be happy to provide our license options, pricing and a copy of the x265 commercial license agreement under a non-disclosure agreement.