private boolean isEmptyLine(int index) {
        int blackCounter = 0;
        for (int i = index; i < index + letHeight; i += H_STEP) {
            if (i >= imh)
                break;
            for (int j = 0; j < this.imw; j += W_STEP) {
                if (j >= imw)
                    break;
                try
                {
                    Color c = new Color(image.getRGB(j, i));
                    int gray = c.getRed();
                    if (gray == 0)
                        blackCounter++;
                }
                catch (Exception e)
                {
                    System.out.println("error in empty line");
                    return false;
                }
            }
        }
        int totalCount = letHeight * imw;
        System.out.println((float)blackCounter);
        if (blackCounter == 0)
//        if ((float)blackCounter/(float)totalCount < EMPTY_EPS)
            return true;
        else
            return false;
    }