Developer discussion for Creative Commons technology and tools

[Dan Mills <dan AT creativecommons.org>]

Hi SIddharth,

Awesome - this is definitely in the right direction, I think.

I just missed you on irc, I'll be on and off today, maybe I can catch you later/tonight.

On DOM changes: performance would be a concern - and it would need to be robust on client-side dynamic apps (which remain loaded and do a lot of JS/DOM work over time, instead of loading new pages on user action). But definitely an area to explore, and we should think about what APIs are more / less appropriate (e.g. we could listen for an event that the app is expected to emit on DOM changes, etc).

On text scanning: yes, agreed.

On fingerprinting: sounds good. we might need to make the web content api aware of fingerprinting for performance reasons in some situations, but your start is good. (by "performance reasons" I mean: perhaps we can do some fingerprinting client-side by dumping images into canvas and doing the math locally--that way we don't need to fetch the image server-side).

Also: it might be likely that users would want to limit scanning to certain classes/kinds of DOM nodes (e.g. all nodes class "article", etc).

Great start!

Dan

On Tuesday, April 30, 2013 at 5:52 AM, Siddharth Kothari wrote:

I built a basic WebContent library which can scan custom medias and

add a solid border if OpenHome service thinks it's a CC-licensed

content. Readme and demo here -

http://sids-aquarius.github.io/webcontent/.

The most glaring missing parts are -

* It doesn't track for changes in the DOM. It should ideally scan for

content in the nodes that are changed.

* Add support for scanning text.

* the fingerprinting is an identity function currently, but the

WebContent library has nothing to do with it.

A code-review would be helpful. It's a small lib (< 50 lines) -

https://github.com/sids-aquarius/webcontent/blob/master/lib/webcontent.js.

I would like to know if I am thinking in the correct direction.

I would also like to know about challenges I should anticipate over

time. Imho, the WebContent project sounds a bit under-scoped. The only

challenge I can think is making this robust to work in a variety of

settings.

Dan - Would you be on IRC sometime today? I wanted to chat about the

fingerprinting library.

Thanks,

Siddharth

On Mon, Apr 29, 2013 at 3:05 AM, Siddharth Kothari

<sids.aquarius AT gmail.com> wrote:

Hi Dan,

I have hosted my fork of Open Home here -

http://106.187.50.124:50124/. Is the schema for the DB laid? I had to

create one and change one of the arguments in getItem() and

updateItem() call, replacing HashKeyElement with the actual attribute

name to get it working. Also, look out for my pull request (it

contains minor fixes).

About the task -

I will wait till we discuss more about the Fingerprinting library.

Meanwhile, I will get started with the Web Content library.

1. For a start, I am planning to build/use a basic html parser that

can fetch all the sources from the <img>/<video>/<audio> tags and send

them over as a json object to Open Home server.

2. The Open Home server returns a json object indicating which of the

contents are CC-licensed.

3. Inject some markup to indicate the contents that are CC-licensed.

As far as fingerprinting is concerned, I will index SHA-1 hashes of

few static content files (or I can hash the files I retrieve from a

user's Dropbox account).

Let me know if you would like to make some amends in the above.

Thanks,

Siddharth

On Fri, Apr 26, 2013 at 7:31 AM, Dan Mills <dan AT creativecommons.org> wrote:

On Thursday, April 25, 2013 at 12:52 PM, Siddharth Kothari wrote:

Hi everyone,

Hello!

I am interested in a couple of projects - CC Web Content API, and Media

Fingerprinting Library. I wanted to see if I understand how these projects

fit in the OpenHome project before starting some contributions.

The way I envision OpenHome is as a central system where the CC licensed

contents will be indexed by their hashes. The CC Web Content API could be

used by sites that aggregate user content, let's say: github, youtube,

slideshare to find out remixing of an existing CC licensed content. The

Media Fingerprinting library helps in determining deduplication of content

(it should also work when a content is cropped, clipped, blurred or quoted

in parts). Am I understanding this correctly?

Roughly, yes. The DB needs to be laid out such that it can be queried from

fingerprint alone (which is not like a MD5/SHA-1 hash). The Fingerprinting

project should aim to catch cropped, distorted, resized, etc. files.

I find the Fingerprinting project fascinating, but delving more into the

idea and looking at pHash.org, I realized it already implements

fingerprinting for image, audio, and video content and provides this as a

nice API - http://www.phash.org/docs/howto.html. Unless we find GPLv3 too

restrictive, I can't think of a good reason to not use this. Perhaps, pHash

can be extended to support for text and compound media types (ppt, pdf). But

I think starting with pHash and supporting text using w-shingling can be a

pretty good start for the fingerprinting library. I would like to hear more

thoughts on this.

I have heard mixed reviews of pHash. I think a first step in the project

should be to come up with a set of tests and metrics, and try out pHash as

well as other solutions.

The CC Web Content API project sounds appealing, since it is the glue that

binds other parts, and perhaps crucial to the successful implementation of

OpenHome project. Imo, this could perhaps be meshed with the Fingerprinting

project (if pHash is used as a base). Essentially, the current

Fingerprinting task is reduced to exposing the pHash library via a nice API.

And over the time, pHash/Fingerprinting algorithms can be added/improved.

Yes, if you'd like to focus on the Web content API, then you can abstract

away the fingerprinting portion. Even straight-up SHA-1 would work for a

demo of the Web content API (it wouldn't catch modified images, but it would

catch the same file in other webpages).

Let me know if I am making sense. Sorry if it's difficult to follow, we can

carry this conversation on IRC. My nick is sids_aquarius.

Sounds good! I'm traveling until Sunday, but will try to drop by when

possible.

Dan