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Comment by Animats | Hacker News Reader

The MP4 patent situation needs another close look. MP4, which was first standardized in 1998, ought to come out of patent soon, if it hasn't already. There are a few remaining patents in the MPEG-LA package, but they're mostly for stuff you don't need on the Internet, such as interlaced video, font loading, error tolerance for broadcast, and VRML. This hasn't been looked at hard since 2011[1] and it's time for a new look. Some of the key patents related to motion compensation expired last April.[2]

It looks like the last patent on MP3 audio decoding expires next month.

[1] http://www.osnews.com/story/24954/US_Patent_Expiration_for_M... [2] http://scratchpad.wikia.com/wiki/MPEG_patent_lists#MPEG-1_Au...

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If by MP4 you are referring to H.264, there are still many years remaining on most of the patents. MPEG-LA publishes patent lists, if you're interested to look.

You are right in that there are many other encumbered technologies that have patents expiring soon. MPEG-1 and MPEG-2 video, MP3 and AC3 audio, and several container formats are included. Notably, this is almost all of the technologies required to make a DVD.

MP4 usually means MPEG-4 Part 2 or MPEG-4 Visual (ISO 14496-2). That's the codec that DivX and XviD implemented.

Yes, MPEG-LA publishes lists, and they need to be looked at closely. Most of the patents have expired. When you go down the list, you see things such as US #6,181,712, which has to do with multiplexing two unrelated video streams into one. Broadcasters and cable systems do this, but Internet video does not. US #6,160,849 only applies to compression of interlaced video, which nobody uses on line. US #7,627,041 is about dealing with missing header data due to transmission noise. US #5,878,080 is about backwards-compatible multichannel (>2 channels) audio, also seldom used on-line. US #6,185,539 is for video with overcompressed extra-low-quality audio. So is US #6,009,399.

MPEG-LA has been padding their patent portfolio by dumping in all these patents on little-used features. Until this year, they still had some good patents, such as the ones on motion estimation, which is a hard problem and is needed to make compression work. But those have now expired. What's left looks like it can be avoided as unnecessary for Internet use.

I think you're right. It's worth the hard look as it would let us take advantage of the existing format instead of push a new one. One's always easier than the other. Looks like we'll be doing same for MP3 soon, too. Glad you mentioned that one as I was going to dodge it for a future project for licensing reasons. Might not have to. :)

If you're looking at new compression ideas, take a look at FrameFree.[1] This is a technology developed around 2005 at Kerner Optical, which was an effects unit of Lucasfilm. It's a completely different approach to compression, not based on frames. It's based on delaminating the image into layers which seem to be uniform in motion, then interpolating by morphing each layer, then reassembling the layers.

Because the interpolation operation is a full morph of a mesh, (which GPUs can do easily) you can interpolate as much as you want. Ultra slow motion is possible. You can also up the output frame rate and eliminate strobing during pans.

Kerner Optical was spun off as a separate company, then went bust. The technology was sold off, but nobody could figure out how to market it. The delamination phase turned out to be useful for 2D to 3D conversion, which was popular for a while. But Framefree as a compression system never went anywhere after Kerner tanked. Nobody is doing much with it at the moment, and it could probably be picked up cheaply. At one point, there was a browser plug-in for playback and an authoring program, but they're gone. I'm not sure who to contact; the "framefree.us" domain is dead. the "framefree.com" domain is dead. Here's its last readable version: [2] The remnants of the technology seem to be controlled by "Neotopy LLC" in San Francisco, which is Tom Randoph's operation.[3]

[1] https://hopa.memberclicks.net/assets/documents/2007_FFV_Comp... (Open with OpenOffice Impress; it's a slide show.) [2] https://web.archive.org/web/20120905065521/http://www.framef... [3] https://www.linkedin.com/in/neospace

Very different type of technology. I could see this being much easier to cheaply accelerate in hardware, too, due to simplicity. Thanks for link! Will keep copies of this and see who's interested.

I don't want to disagree just to be disagreeable, but I don't find much correlation between applicability of patents and their ability to prevent adoption of libre codecs. I've run through a few video patents myself (from the ones Nokia/MS claimed VP8 infringed on) and they were absurdity hidden behind legalize. Daala's approach at taking a radically different design is much more comforting. That being said, even IPR claims have scared off adoption of Opus by Digium : (

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