Lyric synch is not about following the lyrics. Following the lyrics is blindly listening to your music, and if it says "She hopped on a bed eating apples", you put in your video a girl hopping on a bed eating apples. Lyric synch is completely different.
In fact, it doesn't even matter what the lyrics are saying, because what's being said has nothing to do with lyric synch. Lyric synch is, what I like to call, "going with the flow".
For example, if the singer's voice gets louder in the song, you fade in to something. If it gets softer, you fade out. If the words are long and smooth, I'd use long and smooth transitions from each clip. If the words were short and forceful, I would probably just cut from scene to scene.
This description pretty much speaks for itself, but I'll give you some examples anyway.
Singing getting louder, I faded in.
Singing short and forceful, notice my cuts.
The purpose of synching to the lyrics like this is that it usually allows your audience to "feel the groove" of the song. For example, if someone was singing "In the end" and you had something blowing up, you wouldn't have as much of a response as compared to a scene for each word, such as "in" and a missle, "the" the missle hitting something, and "end" where you have a huge nuclear blast. Get my drift?
In this manner, you don't even have to pay attention to action synch at all if you didn't want to, and more often than not, the audience wouldn't mind at all. ^_^
This part of the guide is really small, and that's only because I couldn't figure out how to explain this in simpler terms. All in all, it depends on what you hear, and what you want your video to do.
The synch has nothing to do with the waveform, it has everything to do with your ears. Try looking through the action synch guides and relating what was said there to what is trying to be said here. You may just figure out how to do this better on your own.
Remember that your video can only be as good as you make it. ;)
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