We present a new filter for the Insight Toolkit (ITK) for reducing the resolution of an image by an integer factor while averaging called BinShrink. This filter provides a new level of performance to ITK for reducing resolution and noise present in an image. The filter supports streaming, multi-threading and most of ITK's pixel types including scalars, Vectors, SymmetricSecondRankTensors, and RGBPixels. The filter has been optimized to efficiently access the input image thereby greatly increasing performance over conventional methods.