ress indication/processing termination</h4>
    <pre>        typedef int (*progress_callback)(void *callback_data,enum LibRaw_progress stage, int iteration, int expected);<br>        void LibRaw::set_progress_handler(progress_callback func,void *callback_data);<br>    </pre>
    <p>LibRaw user can set own callback which will be called 10-50 times during
      RAW postprocessing by dcraw_process().</p>
    <p>This callback may terminate current image processing by returning of
      non-zero value. In such c