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RE: Definition for ma:compressions and ma:format

From: Evain, Jean-Pierre <evain@ebu.ch>
Date: Mon, 29 Nov 2010 14:16:17 +0100
To: 'Joakim Söderberg' <joakim.soderberg@ericsson.com>, "public-media-annotation@w3.org" <public-media-annotation@w3.org>
CC: Robin Berjon <robin@berjon.com>, Torbjörn Einarsson <torbjorn.einarsson@ericsson.com>, David Singer <singer@apple.com>
Message-ID: <7D1656F54141C042A1B2556AE5237D60010D37C7CEE6@GVAMAIL.gva.ebu.ch>
How often is RFC4281 (Qualcomm, Apple, Ericsson) used? I remember having seen it being promoted by it authors (fair enough ;-) and the idea is not uninteresting but where is it really implemented?  

Regards, Jean-Pierre

-----Original Message-----
From: public-media-annotation-request@w3.org [mailto:public-media-annotation-request@w3.org] On Behalf Of Joakim Söderberg
Sent: lundi, 29. novembre 2010 11:48
To: public-media-annotation@w3.org
Cc: Robin Berjon; Torbjörn Einarsson; David Singer
Subject: Definition for ma:compressions and ma:format

Regarding the definition for ma:compressions and ma:format.

The response I got from my colleague, Torbjörn Einarsson, is that he agrees with LC comment (LC-2418, Robin Berjon), in that's unclear what to return for "ma:compression" as it is defined now.

"- even something as simple as JPEG can be coded in different ways. The file format was called "jfif", but as we know "jpeg" became de facto."

He suggest that the mime-type (which is well defined) should be in ma:format (as it is) but also include rfc4281 extensions (that describes what's in the file). 
Then consequently ma:compression becomes somewhat obsolete, but it could be used in for the case there are no codec parameters, and then perhaps rename it to "ma:codecs".


substantial: It's unclear what to return for Compression. Is JPEG a compression? Something more specific? Is it case sensitive? Partially controlled?

substantial: Does ma:format include media type parameters?
Received on Monday, 29 November 2010 13:17:00 UTC

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