code: public static int estimatecompress(final int[] in, int currentPos, int inlength) {
  		final int finalin = currentPos + inlength;
  		int counter = 0;
  		while (currentPos < finalin) {
  			int inoffset = fakecompressblock(in, currentPos, inlength);
  			if (inoffset == -1)
  				throw new RuntimeException("Too big a number");
  			currentPos += inoffset;
  			inlength -= inoffset;
  			++counter;
  		}
  		return counter;
  	}
docs: Estimate size of the compressed output.
  
  @param in
  array to compress
  @param currentPos
  where to start reading
  @param inlength
  how many integers to read
  @return estimated size of the output (in 32-bit integers)