/**
  * Set the value of Tesseract's internal parameter.
  *
  * @param key variable name, e.g., <code>tessedit_create_hocr</code>, <code>
  *     tessedit_char_whitelist</code>, etc.
  * @param value value for corresponding variable, e.g., "1", "0", "0123456789", etc.
  */
 public void setTessVariable(String key, String value) {
   prop.setProperty(key, value);
 }
 /**
  * Enables hocr output.
  *
  * @param hocr to enable or disable hocr output
  */
 public void setHocr(boolean hocr) {
   this.hocr = hocr;
   prop.setProperty("tessedit_create_hocr", hocr ? "1" : "0");
 }