Friday, July 11, 2014

The Trankey Do Transformation: How Hard Could It Be to Redub a Two-Minute Dance Video?

This is a long and detailed explanation of the process by which I re-dubbed and extended the Spirit Moves Trankey Do video. As with the video itself, it is possible that this is interesting to no one except me. The video can be viewed here.

Context: An Overview of Spirit Moves

In the 1930s, a German Immigrant dancer named Mura Dehn discovered the Savoy Ballroom, inspiring her to spend decades documenting Jazz Dance. The result is the five-hour documentary Spirit Moves.

If you watch the chunks of Spirit Moves on youtube, you'll notice that the music never quite matches the movement. Recording sound and video was not as simple as it is now, and it appears Dehn simply recorded the dance and dubbed the music in later.

One of the things Dehn captured was the Trankey Do (referred to as the "Trunky Doo" in a Spirit Moves title card, one of many alternate spellings; Wikipedia says it's Tranky Doo, for what that's worth.)

The Beginnings: Learning a Dance from Videos, and a Bright Idea

A few weeks ago, I decided I would teach myself the Trankey Do. There are a number of youtube videos where the steps are broken down and other videos that show it performed. The steps themselves are listed on Wikipedia and LindyWiki.

Everyone seems to do the routine a little differently, so I figured I'd go to the earliest recorded version in Spirit Moves, featuring Al Minns, Leon James, and Pepsi Bethel. (While Pepsi is sometimes credited as the routine's choreographer, swing history Bobby White makes a persuasive case that it was originally choreographed by Frankie Manning and later extended with the simpler final moves by Minns and James.)

Unfortunately, I couldn't dance along to the Pepsi video because the song dubbed in - The Dipsy Doodle - was one beat off. The first move, Fall off the log, traditionally starts on 8, but it was dubbed to start on 1. It felt wrong when I tried to dance along.

I decided to redub the sound to match the dance. I figured it would be easy.

A Simple Tweak: The Right Music on the Right Beat

Because of the Spirit Moves video, dancers nowadays usually do the routine to the Dipsy Doodle, but according to wikipedia and other sources it was originally danced to Erskine Hawkins' Tuxedo Junction. I figured as long as I was changing the soundtrack, I might as well be authentic.

Hawkin's version of Tuxedo Junction on youtube was too slow for the  video, so I edited them together with Vegas Pro 12, which allowed me to speed up the music. I got the speed so it matched the first few eights fairly perfectly and got the opening kick on the 8 where it belonged. I called it a success and uploaded it to youtube.

There was something strange though. While the first part of the video was close to other versions, I found that there were places where the dancers were not doing what was done in the instructional videos; for example, they were doing the knee slap on 7 instead of 8. I assumed that over the years the routine had been altered somewhat, but eventually I realized what the real issue was.

Getting Ambitious: Completing the Routine

The Spirit Moves video does not show the complete Trankey Do, fading out around the Paddles. I found a couple more old Trankey Do videos on youtube. One has only the first third of the routine, but the other, which was danced over the end credits of some old TV show, has Al Minns and Leon James doing the whole thing very fast. The quality is terrible and a big chunk shows Al and Leon in the distance behind the band, but the part missing from the Spirit Moves video is clearly filmed in spite of the credit text. I took that video and slowed it down to match the music. Then I synced it up so the Droop Boogies matched between the two videos and I dissolved there from one to the other.

When I danced along, I realized there was a bit missing from the end - there were only two shouts, instead of four, so I repeated the first shout a couple of times to fill out that section. Then I put it up on youtube, and since you can't replace youtube videos with new versions, I put a link in the first video pointing to this "better" one.

The Realization: This Isn't Right. At All.

I could now dance along to an authentic old school video of the entire Trankey Do routine. But as I did, I found there were some places where the second half seemed out of sync. I edited it again. I felt like there might be a difference between the Spirit Moves and TV Credits versions regarding where the Boogie Drops fell, and put them a couple of beats apart. I uploaded that version, then realized that if I compared the TV credits version with what I'd done, Al and Leon were on different beats entirely. I needed to start again.

At this point I decided to make a basic assumption; regardless of how the routine might have changed over the years, Al Minns and Leon James would be doing the same routine on TV that they did for Mura Dehn. Therefore, both routines should have the Eagle Slide happen on the same count in the same place in the music, and my goal was to make that happen in my video.

But while Al and Leon kicked on 8 on TV, Pepsi was kicking on 2, even though he synced up beautifully in the beginning of the video. So I began to look very carefully at where things went off.

First, there's a cutaway during the second of the Apple Jacks, and I realized that when the video goes back to a long shot, things are no longer in sync. I cut the video there and slid it forward a few tenths of a second until it matched, then stretched the cutaway, which doesn't really sync up well anyway, so it looked fairly seamless.

But that wasn't enough. It seemed as though the dancers were no longer dancing at the same speed. Did the cutaway represent a transition between two different takes?

I tried changing the speed of the dancers, and it got better, but it was still off.

The Realization: I Have Embarked on a Fool's Errand

Then I began to think about the music, and I realized I had been making the foolish assumption that Erskine and the dancers were both keeping the beat with machine-like accuracy.

Was this likely? What were the dancers listening to anyway? A 78 record? A friend with a harmonica?

I got a metronome and checked its beat against Hawkins' song, and sure enough, there is no steady beat that will consistently match that song. It speeds up and slows down, varying by as much as 10 bpm. I found the same thing when comparing the soundless Spirit Moves video against that metronome.

I started watching the Spirit Moves without sound, just counting the steps, and going by the number of steps while ignoring the music, the Eagle Slide appeared to happen on 8. But it wasn't working with the music. For some reason, the dancers rush right before that Eagle Slide, as though that guy with a harmonica sped up or skipped a note and the dancers just kept with him.

At this point I decided to do something extreme. If I counted the dance (as I was editing, I was counting everything outloud), the Crazy Legs after the jump starts on 1. There was no way to make that happen with minor speed shifts. I made a cut in the middle of the jump and slid the whole thing over around half a second, leaving a moment of blank video in its place. Now everything was where it should be - more or less.

I needed to get the TV credits part in better shape. At least here I had the original music as a guide to when they did what step, but once again, beats weren't accurate, and I had to fiddle with some chunks to get things synced up. Not perfectly synced , but enough so that I could dance along without getting totally thrown off.

While I had previously been uploading a new version to youtube every time I completed one, this time I decided to spend some time dancing along with this one to make sure that I finally had what I wanted. This was good, because I kept thinking of further tweaks.

First off, I realized I shouldn't leave Pepsi hanging in the air for 4 beats. I put the jump back together and took a clip of the landing and stretched it out so that Pepsi is simply crouched and waiting for a while. Later I decided it would be better to slow down the section before the jump a little so I didn't have to pad the pause as long, although this created an obvious slow motion quality to the jump.

The jump into the Crazy Legs was still an issue, because I couldn't jump that slow. Studying the video some more, I concluded that it would make sense if he jumped so that he landed on 5 (without the padding he would land on 3 in my edit), then jumped into the squat on 7. I moved thing around until he was making a very slow jump turn on 3 and 4. It was still unrealistic, and it seemed more likely he would start the jump after the 3.  I stretched the first three beats so that instead of putting his foot down on 2 before the jump it doesn't come down until 3. That seemed to make sense, looked more-or-less right, and I could dance along.

And That's It ... I Hope

At this point the Spirit Moves video was as close as I thought I could get it. Oh, I could get it closer if I were to break the video into tiny pieces and stretch and contract each of them to perfectly match the music, and every time I see something that's a little off I'm tempted to move it into place, but I've already sunk hours and hours into this "simple" project and I just can't take much more. It also occurred to me that it might have made more sense - since my focus was on the dance - to edit the music to fit the dance rather than vice versa, but I'll leave that experiment to someone else.

Was it worth it? Perhaps. Breaking the dance down so finely, and doing the steps on the right beat and on the wrong beat (I still think the knee slaps on 7 works really well) means I have an unusually strong sense of how Trankey Do is constructed. But if I knew it was going to take the five or six hours I spent on video editing rather than expected half hour, this video would not exist.