I took your pine cone, dropped it into a comp, selected the layer and used Layer > Autotrace and that created a pretty good mask. If you need it in a shape layer, you would twirl open your mask, select the pine cone "mask path" and copy that. Go to Layer > New > Shape Layer to make your new shape layer. Then twirl open the shape layer "Add" a new "Path", twirl open path, click on the "Path" next to the stopwwatch and paste. Then just add a fill if you need to see it.
Here's a project with the auto trace and shape layer of your pine cone.png.
"I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work."
---THOMAS EDISON on inventing the light bulb.