Quadrature Encoder Question

I got this encoder and it say its 600 pulses/rev.

When I used the encoder library below I get a reading of ~2500 pulse/rev. Is this normal?
http://www.pjrc.com/teensy/td_libs_Encoder.html

leakedazaz:
I got this encoder and it say its 600 pulses/rev.

Incremental Rotary Encoder 600p/r 6mm Shaft 5-24vdc | eBay

When I used the encoder library below I get a reading of ~2500 pulse/rev. Is this normal?
Encoder Library, for Measuring Quadarature Encoded Position or Rotation Signals

Sorry, I think this is a question of how to convert pulse/rev to counts.

There are 4 counts per pulse, so 600 ppr is 2400 cpr.