No amount of analysing is going to give the answer how much silence is added to the track.
Read this for some more info:
http://en.wikipedia.org/wiki/Gapless_playback
I guess that, unlike me, you're not old enough to remember early PC media players that couldn't do gapless playback on the fly, the relief when they finaly came along or the disappointment of early portable devices that again couldn't do it.
Normally this info is embedded in metadata and player just trims it off.
I don't know that it is. You're assuming there is an agreed standard as to how to encode the information that is in use by all media players. Different playback software possibly needs different information in order to know just when to start preprocessing the next track or how to manage the data from the two different streams.
Even if analysis and determining could give that answer, just embed it in metadata and use, it is not going to change.
The assumption that the answer is not going to change holds only if no changes have been made to the algorithm or the track-order of the album since the tracks were first imported and that iTunes identified the tracks as gapless to start with. iTunes often fails to correctly group and order tracks when first imported, an issue I deal with here -
http://samsoft.org.uk/iTunes/grouping.asp - and there have been plenty of new builds during the time I've been using iTunes.
And, regarding crossfade, again - iTunes has no way of knowing in which order you are going to play tracks.
But while playing the current track it knows which track it is about to play next...
If that track is the next seqential track from the same album
and crossfade is enabled
and the (current|next|both?) tracks are marked as gapless
then crossfading will be ignored in favour of gapless transition.
If you(r) iPod behave in such a strange way, there must be something wrong.
My iPod is fine thanks, while my findings are necessarily subjective I'd hoped you would find it a useful indication that iTunes is doing
something when it claims to be doing "Gapless Analysis" and that, just possibly, that
something might even be related to the final user experience.
tt2