Ok, I'll give a detailed explanation of how to use my script.
1. For each movie you want to compare with, you start snes9x, edit the recoder script to indicate which smv file it is going to be run for, then load the recorder script
http://folk.uio.no/sigurdkn/recorder.lua and then play the smv movie. Two files will be created, with names based on what you put in the recorder script.
2. When you have done this for all the movies you want to compare with, you will not need to run the recorder again. Now edit the configuration section of player.lua
http://folk.uio.no/sigurdkn/player.lua to suit your preferences, and indicate the smv files you wish to compare with (these must be smv files for which you have run recorder.lua). The settings are:
moviefile, which is not really relevant for current versions of snes9x-lua. Leave it alone.
others: This is a list of the files you want to compare with. You will want to edit this.
ingame: This is 0 for realtime mode, 1 for realtime synchronization but with skipping of non-realtime frame, and 2 for ingame mode. 0 and 2 are the most relevant.
room: this is false for absolute synchronization, and true for room synchronization. This makes all movies enter each room at the same time, so you can compare each room.
The recorder.lua file used to include an unsupported call to movie.open. I have fixed this now, so try again if you tried yesterday.
To be even more explicit: Say that I have the movies a.smv, b.smv and c.smv, and I want to compare a.smv to the two others. Then I first edit recorder.lua and set moviefile = "b.smv", start snes9x and load recorder.lua. Then, when I am prompted, I start b.smv, and let it run to completion, after which I exit snes9x.
Next, I edit recorder.lua and set moviefile = "c.smv", start snes9x, load recorder.lua and then load the movie file c.smv, let it run to completion, and then exit.
This should have created four files: b.smv.dump, b.smv.index, c.smv.dump and c.smv.index. The purpose of recorder lua is simply to generate these files, so once you have them, you don't need to run it again.
Now, to compare a.smv to these, you edit player.lua. Let's say you want ingame mode with room comparison. Then you make the following changes:
others = { "b.smv", "c.smv" }
ingame = 2
room = true
After this, just start snex9, load player.lua (this could take a few seconds), and then play the movie file a.smv when prompted.
With lua version >= 0.06, you can use savestates with the script, as long as they were created while it was running.