for loop slows down with read(readerobj)

Hello All,

We are manipulating frames of a movie and we are running into a speed issue. Our code loads in each frame of a video one by one and then we extract information from it. What we've noticed is that the first several loops of the code run really fast but it quickly bogs down over time. We've used the tic toc function to see that our algorithm doesn't slow down over time, but the function

 movieFrame = read(readerobj, frameNumber);

gets really slow quite quickly (within a hundred frames). We are using a modest computer (Windows 64, i7, 16G of RAM and a solid state drive).

Is there anyway around this slow down.

Thank you tremendously, Quentin