[Colin Braley]

I’ll try to explain the expression with some comments:

//begin expression

tracks = [ ____ , ______, _____ ,_____ ,_____];
//The line above makes an array of objects that can be referenced
//by using code such as tracks[0] which would be the first tracker
//tracks[2] would be the third tracker
//and tracks[tracks.length -1] would be the last tracker

p = [0,0];
//this line initializes a variable name “p” and makes it an array [0,0]

/*
This next line is where it gets a bit more confusing
I use something called a “for loop” to add up the x and y components of each of the trackers and put them in “p” (the variable i made earlier. for loops follow this syntax:
for( create a variable here; a condition for the loop to end; a condition to increment the variable that will be called at the end of the loop);
It is also good to note that any part of a for loop can be left blank.

Here is what is happening in my for looop:
-create a variable “i” and initiialize it to zero
-add to the x component of p the x componenet of the first tracker
-add to the y component of p the y component of the first tracker
-move on to the next tracker in the arrray “tracks”

Note that i used += (the add and increment operator)
a += b
is the same as saying:
a = a + b;
*/
for(i = 0; i < tracks.length; i++) { p[0] += tracks[i][0]; p[1] += tracks[i][1]; //I could have written this: } //In this last part I divide the x and y componenet of p by the number of trackers //I could have written // [p[0]/tracks.length, p[1]/tracks.length] p/tracks.length //end expression I hope that helps you understand it better. ~Colin

[Colin Braley]

I’ll try to explain the expression with some comments:

//begin expression

tracks = [ ____ , ______, _____ ,_____ ,_____];
//The line above makes an array of objects that can be referenced
//by using code such as tracks[0] which would be the first tracker
//tracks[2] would be the third tracker
//and tracks[tracks.length -1] would be the last tracker

p = [0,0];
//this line initializes a variable name “p” and makes it an array [0,0]

/*
This next line is where it gets a bit more confusing
I use something called a “for loop” to add up the x and y components of each of the trackers and put them in “p” (the variable i made earlier. for loops follow this syntax:
for( create a variable here; a condition for the loop to end; a condition to increment the variable that will be called at the end of the loop);
It is also good to note that any part of a for loop can be left blank.

Here is what is happening in my for looop:
-create a variable “i” and initiialize it to zero
-add to the x component of p the x componenet of the first tracker
-add to the y component of p the y component of the first tracker
-move on to the next tracker in the arrray “tracks”

Note that i used += (the add and increment operator)
a += b
is the same as saying:
a = a + b;
*/
for(i = 0; i < tracks.length; i++) { p[0] += tracks[i][0]; p[1] += tracks[i][1]; //I could have written this: } //In this last part I divide the x and y componenet of p by the number of trackers //I could have written // [p[0]/tracks.length, p[1]/tracks.length] p/tracks.length //end expression I hope that helps you understand it better. ~Colin

[Colin Braley]

When I am averaging multiple tracks I use an expression like this:

//begin expression

tracks = [ ____ , ______, _____ ,_____ ,_____];

//don’t modify below this line

p = [0,0];
for(i = 0; i < tracks.length; i++) { p[0] += tracks[i][0]; p[1] += tracks[i][1]; } p/tracks.length //end expression All you need to do is highlight the spots that say ______ and pick whip to the attatch point property of a tracker. Add as many of these as you want just make sure it uses this format: tracks = [pick whip to tracker one , pick whip to tracker two, pick whip to tracker three ]; On a little sidenote, you could use this script if you wanted to https://www.aenhancers.com/viewtopic.php?t=136
I have never used it before, but it could be helpful if you do this kinda thing alot.
~Colin

[Colin Braley]

When I am averaging multiple tracks I use an expression like this:

//begin expression

tracks = [ ____ , ______, _____ ,_____ ,_____];

//don’t modify below this line

p = [0,0];
for(i = 0; i < tracks.length; i++) { p[0] += tracks[i][0]; p[1] += tracks[i][1]; } p/tracks.length //end expression All you need to do is highlight the spots that say ______ and pick whip to the attatch point property of a tracker. Add as many of these as you want just make sure it uses this format: tracks = [pick whip to tracker one , pick whip to tracker two, pick whip to tracker three ]; On a little sidenote, you could use this script if you wanted to https://www.aenhancers.com/viewtopic.php?t=136
I have never used it before, but it could be helpful if you do this kinda thing alot.
~Colin

[Colin Braley]

To do this you won’t wan’t to track the motion of the head, you will want to stabilize the motion of the head. The process is quite simple, just click the “Stabilize motion” option in the tracker controls pallette. Theres a lot of info on this in the AE Help files too.
~Colin

[Colin Braley]

If you are just trying to crop out the head that you have tracked I would do the following:
– Create a new solid that is the dimensions of the area you want to include.
– Position it over the head and then link the new solid layer’s position to the attatch point of the tracker that tracks the head. Make sure this layer is directly above the layer containing the footage of the head.
– Set the layer with the footage of the head’s Track matte to “Alpha matte.” Then you should have a nice crop of the head.

This will definetly work, but maybe someone has a less convoluted workflow you could follow.

~Colin

[Colin Braley]

haha A.N you beat me to it 🙂 I was typing in my response while you posted yours. Nice explanation btw.

[Colin Braley]

This behavior is normal and this will happen no matter how you do stabilization. What happens is the computer tracks a point in the clip and finds how much it strays away from it’s original position. The inverse of this data is then applied to the motion of the clip to stabilize it. Essentially, AE tries to track your object and keep it in the middle of the frame. It does this by moving the clip around. Therefore the clip will inevetablely no longer fill your frame perfectly. You can scale the clip up to make it cover the whole screen. Before you do this remember that the edges of your clip will be clipped if you are outputting to TV so you might not have to worry about it. This is kindof a hard topic to explain in words, if you have the Myer’s “Creating Motion Graphics- Volume 2” I recomnend reading the section on stabilization it’s quite helpful.

[Colin Braley]

AE can’t really natively do 3d exruded text. I would reccomend using Zaxwerks as you mentioned or doing whatever you need to do in a 3d program if it is sophisticated. If you just need some quick, non-bevelled 3d text you can fake it with the shatter effect and use AE’s cameras. Roland Kahlenberg made a tutorial on this I believe, do a quick search and you wil find what you are looking for.

~Colin

[Colin Braley]

I have both AE 6.5 and 7.0 installed on Windows XP Pro and I have not noticed any problems, or heard of any from anywhere else.
~Colin