Credits & Codec Licensing
The desktop app ships four engines inside it and invokes a few more that you install yourself, each under its own licence. The web app sends open-source engines to your browser tab and leans on WebCodecs, the codecs your browser vendor already ships, for video. This page names who does the work and the patent considerations some formats carry.
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The web converter at teraconvert.com runs conversions inside your browser tab using a small set of open-source engines that ship with the page: Mediabunny (WebCodecs), pdf-lib, PDF.js, mammoth, jSquash, gifenc, PaddleOCR, and U2-Net by Xuebin Qin and colleagues, which separates a subject from its background. That one is a model rather than a library, so we serve its weights from this domain under the Apache 2.0 licence they carry. These engines do the actual encoding and decoding work; we ship them to your browser but the file bytes never reach our servers.
The desktop app ships four engines inside the bundle: FFmpeg 8.1.2 for video and audio, Tesseract 5.5.3 for reading text out of images, and qpdf with pdfium for PDFs. Nothing to install. What is left runs as a separate process on your machine, with office documents going through LibreOffice, e-books through Calibre, a few document formats through Pandoc, and Ghostscript for the two PDF jobs pdfium cannot do, compressing a file and editing its metadata. You install those through Homebrew, and the app offers to do it at the moment a file needs one. We do not redistribute them, so your relationship with each is governed by that tool's own licence and by your OS distribution. On macOS the app also calls Apple's own tools: sips, textutil and qlmanage, plus the Vision framework, which is what removes a background there. Vision is part of macOS, so there is nothing to download and nothing to license. The About screen lists the licence notices for what we ship; if you believe an attribution required by an open-source licence has been missed, write to contact@teraconvert.com and we will fix it.
Some of the formats TeraConvert can read and write are covered by third-party patent pools. This is a property of the format itself, not of TeraConvert.
H.264 / AVC, H.265 / HEVC, H.266 / VVC, AAC, MPEG-2, and MPEG-4 visual are covered by patent pools administered by Via Licensing Alliance (which absorbed MPEG-LA in 2023). Distribution, broadcast, or large-scale streaming of content encoded with these codecs may require a separate licence from the pool administrator in some jurisdictions.
Where the source allows it, target AV1, VP9, or WebM for video, Opus, FLAC, or WAV for audio, and AVIF or WebP for images. These formats are designed to be royalty-free. We recommend them whenever they fit your use case.
You are responsible for ensuring that your particular use of any patented codec (especially commercial use, broadcast, or large-scale distribution) complies with the licence terms of the relevant pool in your jurisdiction. TeraConvert does not pay a downstream patent royalty on your behalf.
Useful references: Via LA AVC / H.264, Via LA AAC, FFmpeg legal, Alliance for Open Media (AV1 / AVIF), Opus.
LGPL source availability
The web app bundles no FFmpeg. Every conversion in the browser runs on Mediabunny and the browser's own WebCodecs and Web Audio APIs.
The desktop app ships a build of FFmpeg 8.1.2 that we compiled from unmodified upstream source, configured for the LGPL v2.1 alone: no GPL components, no x264 or x265, and the LGPL dependencies it needs, LAME and mpg123, linked in statically. We publish the complete and corresponding source for all three next to the binary, together with the exact configure line used to build it and the full licence text. The other codec libraries in that build, Opus, libvorbis, libogg, libvpx and dav1d, are BSD licensed and need attribution rather than source. The other engines we ship carry no source obligation either: Tesseract and qpdf are Apache 2.0, Leptonica is BSD 2-Clause, and pdfium is BSD 3-Clause together with the fourteen third-party licences shipped in the PDFium distribution, all of which travel inside the app. Take a copy of the FFmpeg side whenever you want it: the FFmpeg source, with LAME, mpg123, the configure line and the licence text beside it.
If you would like a written copy of the LGPL or believe an attribution required by it has been missed, write to contact@teraconvert.com.
The fonts used on this site are open-source under the SIL Open Font License.
| Font | Role | License |
|---|---|---|
| Caveat | Hand-drawn accent typeface used for marketing annotations. | SIL Open Font License 1.1 |
FFmpeg is a trademark of Fabrice Bellard, ImageMagick of ImageMagick Studio LLC, Pandoc of John MacFarlane, Ghostscript of Artifex Software, LibreOffice (registered) of The Document Foundation, and Calibre of Kovid Goyal, while macOS, sips, textutil, and QuickLook are trademarks of Apple Inc., registered in the U.S. and other countries. All other product names, logos, and brands are property of their respective owners. Use of these names does not imply endorsement.
The AI text cleaner shows the marks of OpenAI, Anthropic, Google and xAI to say which assistants it is meant for. Those marks belong to their owners, the artwork comes from the MIT-licensed Lobe Icons set and is shown unmodified, and none of it means those companies are involved with TeraConvert or have approved it. Any owner who would rather we drop their mark can write to contact@yogendrasingh.in and we will.
Disclaimer. This page is provided for informational and attribution purposes. It is not legal advice. Patent licensing requirements vary by jurisdiction, intended use, and specific codec implementation. If you have concerns about open-source compliance or codec licensing, particularly for commercial use, please consult a qualified legal professional. TeraConvert makes no warranty as to the patent-free status of any codec, container, or conversion method, and accepts no liability for third-party tools that you install on your own machine.
See our Terms of Service and Privacy Policy for the rest of the agreement between you and TeraConvert.
