- From: Ralph Giles <giles@mozilla.com>
- Date: Tue, 27 Nov 2012 14:24:57 -0800
- To: whatwg@lists.whatwg.org
On 12-11-27 9:19 AM, Gordon P. Hemsley wrote: > Is it sufficient to sniff just for "application/ogg" and then let the > UA's Ogg library determine whether or not the contents of the file can > be handled? (I'm sensing the consensus is yes.) I think so. Defining a codec enumerating algorithm and mime type decision tree is going to be several pages of spec for container formats like Ogg and Matroska. As an example, the 'file' tool reads the first codec header present in an Ogg file, which can be found at a set of fixed offsets. This lets it get some useful information for a lot of files, especially since it's RECOMMENDED that primary codecs are listed first. I.e. theora should be first in a 'video/ogg', opus should be first in an 'audio/ogg; codecs=opus'. But files can be muxed without following the priority rule and will still play fine, and there can be a 'skeleton' header in front of the other codec data, obcuring primary role. Just looking at fixed offsets isn't sufficient to distinguish audio and video reliably. IMHO, -r
Received on Tuesday, 27 November 2012 22:28:11 UTC