That's a representation of where you are in model space as you walk along the bitstream of a sound file. Each step is 640 bits. The red curve plots the CIC value for explaining the bits as a sample from a complete bitnet of size 2,3, ..., 10. The green arrow represents change in complexity. The size of the green arrow is proportional to the Kullback number between (the best model of) where you are and where you are going to. The head of the arrow points up if the increment in CIC is >0 and down if negative. The vertical green lines appear each time the place where CIC is minimal changes, so that there is a change in model dimension. The structure of the .aiff file: wrapper+header+data is clearly displayed. Can you tell the times of the boundaries?