I picked out that your front knee if very stiff and straight a lot of the time. Most of your weight seems to be at best centered and a bit more to the back, especially when you have that front knee locked.
You seem to initiate the turns with your hips giving you the skidded turns. These are fine if this is how you are trying to turn.
Your camera work gives a great view of your feet showing that there is no torsional twist on your front foot to start your turns to pull the board into the turn giving you that sharp turn or carve.
Like Donutz said, you should see a clean line in the snow behind you, not spray.
Wolf will nail it down for sure he has this answer on file and then modified for each rider. He is stronger at pointing this out than me but this is what I see.