Faster RCNN code in Matlab

Hello,

I am tring to run Faster RCNN code in Matlab.

I took matlab vehicle example and run it on my DB.

My image size is 901x1201.

I want to reduce it because I get out of memory error.

The first thing I need to do is the resize the images.

1. I want to use 'SmallestImageDimenstion SmallestImageDimenstion' to do that but I am not sure I know how to use it and what it does exactly.
2. I want to keep the proportion if my image dimention, for example to increae each axes in half. How do I do that?
3. Does it effected from the size of the object I want to find?

Thx