Papagayo is a great (and free) program made by Mike Clifton and is distributed by LostMarble.com. Papagayo is designed to help you line up phonemes (mouth shapes) with the actual recorded sound of actors speaking. Papagayo makes it easy to lip sync animated characters by making the process very simple - just type in the words being spoken (or copy/paste them from the animation's script), then drag the words on top of the sound's waveform until they line up with the proper sounds.
Papagayo Lip Sync Support in Spriter Pro

# Spriter Pro User’s Manual version 1.0

Quickstart
Sprites
Bones
Animating
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TM
Papagayo can be downloaded from http://www.lostmarble.com/papagayo/ for either Windows or Mac. To add lip syncing to your Spriter animation you must follow the following steps after installing Papagayo:
1) Start Papagayo and load up your WAV file containing the dialogue into Papagayo by dropping the file into the designated spot in Papagayo’s window. Then in the “spoken text” window, type all of the words spoken in the sound file in their propper order. once you do so you’ll see orange blocks representing all the individual words spread out across the graphic representation of the sound file. Now left click and drag on the beginning block or the ending block of each word to properly make each word start and end properly according to the actual sounds.
2) Once all the words are properly alligned, export the file (DAT) from Papagayo making sure to have the export mode set to Anime Studio. (it is by default). Then make sure the sound file. (WAV) and the DAT file from Papagayo are in your Spriter projects folder, either directly or in a sub folder.
4) In Spriter, once the animation is otherwise finished, add the sound file at the proper point in the animations time line. IMPORTANT: Because the next step in the process will permanently add a very large amount of key frames to the animation, which would make editing the animatio after the fact very difficuly, we highly recommend you first create a clone of the animation as a back- up BEFORE you proceed to step 4!
5) Assuming you’ve made a backup copy of your otherwise finished animation as described above, now just find and right click on the graphical representation of the sound file in the timeline, and choose “import lip sync”. Then a small dialogue box will appear asking you to choose the lip Sinc File (This is the DAT file exported from Papagayo) and the “Mouth Timeline” (this is asking for the name of the object timeline, aka the sprite which Spriter will be image swapping to prepresent all the mouth shapes for the lip syncing. Once these options are set properly, click OK and the lyp syncing process should add all the necessary keyframes to the animation in order to change the mouth image at the apropriate times to represent the sound being made at that moment in time. Remember, if you need to change the animation after importing the lyp sync, you should once again copy the back up of the animation that was created BEFORE the import of lip sync, edit the copy, and then re-iumport the lip sync. This process will ensure you always have a clean, lip sync free version of the animation to change and edit as needed.
3) In order for lip syncing to work, you need to have created a series of swapible mouth images, each carefully designed to represent the pronounciation of specific sounds that people make while speaking. Each file must be carefully named exactly like the reference chart above shows. Create a folder in your Spriter project folder for each of the angles the mouth will be seen from...for example a folder called “mouth_sideview” and one called “mouth_frontview” and put all the apropriate mouth images into their folders. The animation you’ll be aplying lip sync to should already have one of these mouth images present throughout the entire timeline, the “rest” image for example. If your head changes angles within the animation, you can image swap the mouth image at that point in the timeline from the mouth image “rest” in one folder to the “rest” image in the forlder for the diferent angle...such as changeing from front view to side view. (you can find other mouth shap references here: http://www.brashmonkeygames.com/spriter/Papagayo/PapagayoMouthShapes.html)