Problems with applying corner pin data on a footage with alpha channel


#1

Hello.

I’ve tracked a footage and copied After Effects Corner Pin data to clipboard.

Before pasting the data to the target footage, I tested it on a solid layer. Everything worked very well.

So then I pasted the data to my target footage (the footage is of the same size as my comp, CTI set at 00:00:00).

However, after I had pasted the tracking data to the footage layer, it became an extremely small, barely noticeable dot. It follows the track all right, but it is almost invisible tiny dot. What could be the reason of this? Why it works well with a solid of comp size, but not with the footage of comp size?

My target footage has this history:

  1. It was recorded in .mts format, 1920x1080, 50fps. (my project comp is also 1920x1080, 50fps)

  2. Then it was imported to AE, stabilized. Then an area of interest was masked out

  3. Then the comp with the area masked out was rendered to .mov file (Animation codec, RGB+Alpha)

  4. And finally I imported this .mov footage to my main comp and now trying to apply tracking data from mocha

Also, the masked out (visible) area in my target footage is not located at the exact center (where the anchor point is). Does it have any significance? I tried to put the anchor point on the visible part and then apply corner pin data, but then the whole target footage became invisible


#2

The mask could be defining the size of the layer which means it’s no longer the same size as the footage. Try removing the mask and see if your layer matches.

Are you exporting a full-frame aligned surface, or just the surface positioned around the target area?


#3

Hi Martin,

the mask no longer exist, since I pre-rendered my comp with mask into a .mov file with alpha channel. (I had a raw footage of a human face and I masked out the eye area. So now i have a .mov footage with only the eye visible and all the rest is transparent).

And yes, I exported the surface around the target area.

I think i will try to scale up the footage and re-render, so that the eye covers larger area of the footage, maybe it will help


#4

Yes, it works OK now. My footage had a too small visible area (and a lot of transparent pixels).