Hello again 2kaud and Paul,

After build the project as Paul said, the speed is better, but it seems still is very slow compare with the small ruby code I mentioned in my first post. I'm not sure why, the ruby code processes a 2GB file in 7 min and a 20MB file ina few seconds, but I've tested the C++ code with a 20MB file and waiting for more than 10 min and only the 10% of the file was processed

I don't have idea where to modify in order to enhance the processing speed in a good manner.

Maybe you can have an idea.

Thanks again.