View Full Version : Keyframes vs. Sound on the timeline

09-21-2006, 01:28 PM
I'm not sure if anyone else has had this problem, and it's a bit difficult to explain. I'm currently working on a flash "slideshow," with voiceovers. The voice tracks are mp3 files stored in the library. I'm simply placing them on the timeline so that i can sync up my bullet points that appear with the times the voice plays in the audio tracks. Simple right?

Well, it turns out that the bullet points and the voice tracks sync up perfectly in the preview mode, and even when i view them as SWF files. As soon as i load these SWFs into another movie and play them in a browser, the bullet points are appearing well after they should be.

The problem stems from areas where i have multiple bullet points for one LONG voice track. Although the keyframes and the peaks showing up in the timeline are perfectly aligned (and the preview confirms this!), the actual display of the bullet points are delayed. Both movies (the externally loaded SWF and the holder SWF) have the exact same frame rate.

Does this make sense? Has anyone run into this before?

09-22-2006, 04:38 PM
I have had similar problems in the past. I think it is because flash triggers the sound which then plays independently of the timeline as a sound object. The timeline plays along with it but if it encounters a problem (other network traffic, CPU usage etc) it slows down to compensate and gets out of sync. Obviously this problem gets worse the longer the time line is.

This is only the explanation I came up with from doing tests for myself and may be wrong (i would like to hear from people who know for sure) but it makes sense.

I have heard that you can add trigger points to .flv files that trigger functions in the parent movie, can you do the same with .MP3s maybe? or is this just a rumour I have made up?

09-26-2006, 01:58 PM
Thanks, that DOES seem to make sense. What doesn't seem right to me are all those "flash music videos" floating around the interweb. The authors HAVE to be using one big long mp3 file that the text and animations are being synced to.

Unless, of course, the sound isn't being imported directly on the timeline, but rather using actionscript. But then you wouldn't have the waveform to try and sync your events up against, which could be problematic during authoring time.

Has anyone else found a workaround for this problem, such as forcing the sound to stream with the timeline or something? I'm really grasping at straws here. :confused:

09-27-2006, 03:34 AM
Removed for lack of interest.