windows media codec's availability

[extra]

When developing an application using DMO, say WMA 9 encoding, we want to make sure this program can run on a user's machine. But how can we make sure the dll is available on the user's machine? I saw in windows media SDK's documentation that WMA 9 codec requires Windows Vista or Windows XP. Can I say that any user with these OS can use WMA 9 encoding for sure? How about users with 64 bit version Vista or XP?

Also I read in the VC1's FAQ that Vista 64bit provides both 64 bit and 32 bit version of DMO. How are they differentiated, by filename? How can I explicitly designate using one over the other?

I am really confused about this part. So please forgive me if my question doesn't make a lot of sense...

[LoRd_MuldeR]

I think you will need to ship the Windows Media Player or at least the Windows Media Format Runtime (http://www.citizeninsomniac.com/WMV/wmfdist11.exe) along with your application....

[benwaggoner]

I think you will need to ship the Windows Media Player or at least the Windows Media Format Runtime (http://www.citizeninsomniac.com/WMV/wmfdist11.exe) along with your application....
That's correct, for XP.

Vista and Win 7 have what they have; there's nothing to update beyond that.

Note that XPSP2 and higher already has at WMP 9, and so will support WMA 9.2 and back to the dawn of time. The only two codecs you might care about not in WMP 9 are WVC1 (advanced profile) and WMA 10 Pro LBR decoder. Both of those are included with WMP 11, and so an app can include the redistributible for that, or for just the Format Runtime, which adds the new codecs, but won't change the player.