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From: Jan Lindquist <jan.lindquist@ericsson.com>
Date: Tue, 1 Nov 2011 09:21:50 +0100
To: Clarke Stevens <C.Stevens@cablelabs.com>, "public-web-and-tv@w3.org" <public-web-and-tv@w3.org>
Message-ID: <82276AE38FD87A4C9CF6C820AC5276EA3478E5F22B@ESESSCMS0362.eemea.ericsson.se>
Hello Clarke,

I would appreciate having these additions added to the TPAC slides. The only comment I received were positive.

As requested in the phone conference in the last MPTF I have provided examples of additions to "suggested changes" with the work done in OIPF. These additions provide concrete examples of deployments that W3C can refer to. A hot topic is related to DRM and in the examples I have a list of examples of information that is exchanged like error codes, state changes, etc. 

Thank you,

-----Original Message-----
From: Clarke Stevens [mailto:C.Stevens@cablelabs.com] 
Sent: den 31 oktober 2011 21:37
To: public-web-and-tv@w3.org
Subject: Re: [MEDIA_PIPELINE_TF] Updated TPAC slides

One mover version. I added references to LC bug 12399.


On 10/31/11 12:26 PM, "Clarke Stevens" <C.Stevens@CableLabs.com> wrote:

>Here are the slides with some additional updates after discussions on 
>the MPTF reflector. This is the deck I plan to use for discussions with 
>the HTML WG.
>I will prepare a simplified version of this deck for presentation at 
>the plenary session. I'll send this out later today.
>On 10/27/11 4:25 PM, "Clarke Stevens" <C.Stevens@CableLabs.com> wrote:
>>I made changes to the slides based on feedback during the meeting and 
>>some emailed comments afterwards. Please let me know of any other 
>>suggested changes.

attached mail follows:


The references to OIPF in these areas are very helpful.

We should also include a reference in R7 to this excellent survey of video parameters in existing systems:

and reference the related LC1 bug 12399.


On Oct 30, 2011, at 1:53 AM, Jan Lindquist wrote:

Hello Clarke,

Here is the proposed text for the slides relating to suggestions on adaptive streaming and content protection. Note I did not manage to find "errors" when it comes to adaptive streaming. It felt more like an exachange of information rather than an error. I believe that the errors are fairly well covered. This may be simply an issue of interpretation.


Slide 4, R7 Adapative Bit Rate Parameters
Suggested changes:
- Receive events on change in representation of adaptive stream like quality.  This information provides statistics as to what representations were used and at which bandwidth for a given content.
- Receive events on change of periods of adaptive streaming. If live content has different manifests over time this event describes what future representations are available which allow change set limits as described below.
- Set limits on adaptive streaming upper and lower limits representations. The limits help provide a better video rendering experience and can be used depending on circumstances.
[This example is taken from OIPF DAE specification. Refer to Section 7.14.8 Extensions to A/V Control object for UI feedback of buffering A/V content]

Slide 6, R10 Content Protection Parameters
Suggested changes:
- Retrieve DRM system information like DRM system is ready, it is initializing, error, etc.
- Exchange DRM related messages with the underlying DRM system.
- Result on exchange of DRM related messages if exchange is successful or an error occured. Errors may include user consent is required, unknown DRM sytem id for incoming content, wrong format, etc.
[This example is taken from OIPF DAE specification. Refer to Section 7.6 on Content Service Protection]

Slide 7, R11 Content Protection Errors:
Suggested changes:
Receive errors from DRM system and receive additional information like DRM rights URL for retrieval of keys. Errors may include
- No license
- Invalid license
- Valid license
[This example is taken from OIPF DAE specification. Refer to Section 7.13.6 on Extension to video/broadcast for DRM rights errors]
Received on Thursday, 3 November 2011 00:26:26 UTC

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