On 23/10/05 1:14 AM, "James M Snell" <[EMAIL PROTECTED]> wrote:
> The challenge with using alternate to point to files of different types > is that why would someone do (a) when they can already do (b) without > the help of a new extension > > (a) > <link rel="enclosure" type="audio/mpeg" href="http://example.com/file.mp3";> > <x:alternate type="application/ogg" href="http://example2.com/file.ogg"; /> > </link> > > (b) > <link rel="enclosure" type="audio/mpeg" > href="http://example.com/file.mp3"; /> > <link rel="enclosure" type="application/ogg" > href="http://example2.com/file.ogg"; /> With (b), how could you ever then provide multiple distinct enclosures for an entry. With (b) you're trying to say that the two sound files are the same thing, just different formats. For example, I might want to provide a movie file with commentary, and another movie file without commentary, and a third movie file showing just the special effects part in slow motion. They are not substitutes for each other. With (a), we know the .mp3 and the .ogg are simply different formats of the same thing. With (b) we don't know either way. > What I want is a way of indicating that a particular resource is > available at multiple locations. I'll use multiple link elements to > indicate that there are multiple formats. And some aggregators will treat that as a basket of different enclosures and try downloading all of them. >> it would be fair to say that any two x:alternate with different @href's but >> equivalent x:md5 are mirrors. That can fit into the model with no other >> modifications :-) >> > I would argue that the x:md5 for all alternates should be the same as > the parent link. > What about this though: <entry xml:lang="en"> <link href="1" rel="enclosure" type="audio/mpeg" x:md5="hash1" title="soundtrack"> <x:alternate href="2" type="audio/mpeg" x:md5="hash1"/> <x:alternate href="3" type="audio/mpeg" x:md5="hash1"/> <x:alternate href="4" type="audio/mpeg" x:md5="hash1"/> <x:alternate href="5" type="application/ogg" x:md5="hash2"/> <x:alternate href="6" type="application/ogg" x:md5="hash2"/> <x:alternate href="7" type="application/ogg" x:md5="hash2"/> <x:alternate href="8" type="audio/wav"/> </link> <link href="9" rel="enclosure" type="audio/mpeg" title="commentary"> <x:alternate href="10" type="audio/mpeg" hreflang="pt"/> </link> </entry> Here we have an entry with two enclosures. The first enclosure is the soundtrack, and is available in mp3 from one primary URI and three mirrors, and also available in .ogg from three mirrors, and for the truly desperate also available as a .wav file. The second enclosure is a commentary sound track, but not available in any other formats or from any other mirrors, but there is a Portuguese translation variant if you (really) want. e.
