W3C home > Mailing lists > Public > public-html-media@w3.org > May 2014

Re: [EME] To what extent should EME support usage rules?

From: Joe Steele <steele@adobe.com>
Date: Wed, 14 May 2014 21:11:10 +0000
To: "Maruyama, Shinya" <Shinya.Maruyama@jp.sony.com>
CC: "public-html-media@w3.org" <public-html-media@w3.org>
Message-ID: <FFBD4224-B973-4E56-9B36-D57ECA124570@adobe.com>
There are a couple of additional usage rules that have been mentioned.

There has been discussion of usage rules around output protection (e.g. HDCP). This used to be represented via an error code, but that has gone away at this point. 

There has also been discussion around output downscaling in bug 25092.

My opinion is that the application only needs to know about things that might be impacting playback. 

For example:
* When a key is no longer available because it has expired. What type of expiration occurred and the exact times makes less sense to me. 
* When playback has stopped because output protection has been violated. Again the type of OP failure makes less sense to me. 
* When playback has degraded for some reason (e.g. OP failure). 

There are lots of other usage rules (geolocation, domain membership, etc.) but I think most of these can be invisible to the application and handle on the server side. Do you have a specific policy in mind that we do not have?


On May 13, 2014, at 12:07 AM, Maruyama, Shinya <Shinya.Maruyama@jp.sony.com> wrote:

> Now expiration time is the only usage rule EME API supports by Bug 25537.
> Is the expiration time sufficient for the envisioned use cases? or
> Is there still the room to add other parameters?
> For instance, in case of rental video, start time and period after first use are used in general.
> In this case, constructing UI only by expiration date might be confusing to users because end time shortens after first use implicitly.
> As to start time, it might be useful if video is upcoming movie; i.e. start time is future time.
> Honestly, Iím not sure what is the criteria to decide which usage rules are common concept in EME world.
> Any opinion?
> Thanks,
> Shinya

Received on Wednesday, 14 May 2014 21:11:46 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 15:48:49 UTC