In file DCTStream.cc:75 at method init() field cinfo.err is initialized after call to jpeg_create_decompress(&cinfo) and this makes a segmentation fault when an error thrown while calling this function (jpeg_create_decompress).

The correct usage should be like this:
void DCTStream::init()
{
  jpeg_std_error(&jerr);
  jerr.error_exit = &exitErrorHandler;
  cinfo.err = &jerr;
  src.pub.init_source = str_init_source;
  src.pub.fill_input_buffer = str_fill_input_buffer;
  src.pub.skip_input_data = str_skip_input_data;
  src.pub.resync_to_restart = jpeg_resync_to_restart;
  src.pub.term_source = str_term_source;
  src.pub.bytes_in_buffer = 0;
  src.pub.next_input_byte = NULL;
  src.str = str;
  src.index = 0;
  src.abort = false;
  cinfo.src = (jpeg_source_mgr *)&src;

  jpeg_create_decompress(&cinfo);
  x = 0;
  row_buffer = NULL;
}