Automat the Auto-Trace process

Hi guys,

I'm new on this forum and wanna ask you all, is someone knowing about a script or expression that will automate the process Auto-Trace (Alpha png to Masks) Without AE UI.What i mean is,

01_When I want to use .PNG image (Alpha) in Element 3d than i use auto track in AE.(suppose everything goes fine)

02_Next time if i change the source image (.png image which we used earlier).

03_And if I open the project again so now the mask comes in the shape of the new .png image.

I have given a link below to explain this process.

https://www.youtube.com/watch?v=-t5IbvGfWcQ&feature=youtu.be

Thank you