Add Meta Seal watermarking algorithms (PixelSeal, ChunkySeal, VideoSeal, AudioSeal, TextSeal)

[carlreid]

Registers some of the open source watermarking algorithms from Meta Seal suite as soft binding algorithms for C2PA:

ID	Algorithm	Type	Media
33	com.meta.pixelseal.1	watermark	image
34	com.meta.chunkyseal.1	watermark	image
35	com.meta.videoseal.1	watermark	video
36	com.meta.audioseal.1	watermark	audio
37	com.meta.textseal.1	watermark	text

I noticed the com.aiwatermark related entries, which appears to be a paid service exposing these same models. If I understand things correctly, then this algorithm list is to be used as a list of potential watermark implementations that would be required to detect all potential cases of content using a C2PA Soft Binding? Which leaves me a little concerned that it could lead to many paid providers re-exposing open source models, such that ultimately the C2PA manifest can't be discovered without paying for access. It seems a little counter intuitive to define an interoperable Soft Binding API spec, yet providers can register here behind paywalls.

I have also included an additional fix in README.md from softbinding-algorithm-list-schema.json to softbinding-algorithm-list.schema.json.

[jcollomosse]

In light of submission policy:
The PR shall be submitted by an individual affiliated with the company owning the submitted proprietary algorithm or a maintainer of the submitted open source algorithm or its fork.
please can you confirm that you have permission from Meta to register entries within the meta.com namespace.

[carlreid]

Ah, I've emailed opensource@meta.com asking if they can grant permission or otherwise comment here.

Regarding the policy quoted policy. On what grounds did #43 get approved? Would that count as a fork? Though as far as I can read, it's essentially a service utilizing these Meta models as is?

[domguinard]

@carlreid indeed #43 is a for of an open-source WM algorithm. The fork is what was submitted and this is complying with our policy:

The PR shall be submitted by an individual affiliated with the company owning the submitted proprietary algorithm or a maintainer of the submitted open source algorithm or its fork.

Feel free to join the watermarking task force if you'd like to contribute and discuss the approach.

[carlreid]

Thanks for the insight @domguinard.

Feel free to join the watermarking task force if you'd like to contribute and discuss the approach.

Would that be via https://lists.c2pa.org/g/twg?