djet.c

This is code tutorial for image processing include:histogram,sketon....

    *
    *   Print the two arrays to make a 100x200 output.
    *   To do this you loop over 100 rows, set the
    *   r buffer to the image values, set the
    *   graphics, and print the row via function
    *   print_original_200_row.
    *
    *************************************************/

   for(i=0; i<100; i++){
      for(j=0; j<100; j++){
         r[j]     = image1[i][j];
         r[j+100] = image2[i][j];
      }  /* ends loop over j */

      end_graphics_mode(printer);
      select_300_dpi_resolution(printer);
      set_raster_width(printer);
      start_raster_graphics(printer);
      select_full_graphics_mode(printer);

      print_original_200_row(printer, r);

      printf("\n\tPrinting row %d", i);
   }  /* ends loop over i */


      /**********************************************
      *
      *   If show_hist is 1 then calculate the 
      *   histogram for the two image arrays and 
      *   print the histogram.
      *
      ***********************************************/

   if(show_hist == 1){
      if(color_transform[0] == 'S'){
         calculate_histogram(image1, histogram);
         calculate_histogram(image2, histogram);
         print_hist_image(printer, histogram);
      }
      if(color_transform[0] == 'H'){
         print_hist_image(printer, final_hist);
      }
   }

        /*********************************************
        *
        *   Print a couple of blank lines then print
        *   the caption.
        *
        **********************************************/

   end_graphics_mode(printer);
   strcpy(page, "      \n");
   fputs(page, printer);
   fputs(page, printer);

   sprintf(page, "                      %s\n", caption);
   fputs(page, printer);

   fputc(FORMFEED, printer);

   fclose(printer);

   printf("\nEnd");

}  /* ends print_graphics_image */



   /******************************************
   *
   *   get_graphics_caption(...
   *
   ******************************************/

get_graphics_caption(caption)
   char caption[];
{
   printf("\nEnter the caption to be printed\n---");
   gets(caption);

}  /* ends get_graphics_caption */




   /************************************************
   *
   *   select_full_graphics_mode(...
   *
   ************************************************/

select_full_graphics_mode(printer)

   FILE *printer;
{
   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('b', printer);
   fputc('0', printer);
   fputc('M', printer);

}



   /************************************************
   *
   *   set_horizontal_offset(...
   *
   ************************************************/

set_horizontal_offset(printer)

   FILE *printer;
{
   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('b', printer);
   fputc('4', printer);
   fputc('9', printer);
   fputc('6', printer);
   fputc('X', printer);

}





   /************************************************
   *
   *   set_shorter_horizontal_offset(...
   *
   ************************************************/

set_shorter_horizontal_offset(printer)

   FILE *printer;
{
   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('b', printer);
   fputc('4', printer);
   fputc('8', printer);
   fputc('0', printer);
   fputc('X', printer);

}





   /************************************************
   *
   *   end_graphics_mode(...
   *
   ************************************************/

end_graphics_mode(printer)
   FILE *printer;
{
   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('r', printer);
   fputc('B', printer);
}



   /************************************************
   *
   *   set_raster_width(...
   *
   ************************************************/

set_raster_width(printer)

   FILE *printer;
{
   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('r', printer);
   fputc('2', printer);
   fputc('2', printer);
   fputc('0', printer);
   fputc('0', printer);
   fputc('S', printer);

}




   /************************************************
   *
   *   start_raster_graphics(...
   *
   ************************************************/

start_raster_graphics(printer)

   FILE *printer;
{
   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('r', printer);
   fputc('0', printer);
   fputc('A', printer);

}




   /************************************************
   *
   *   select_300_dpi_resolution(...
   *
   ************************************************/

select_300_dpi_resolution(printer)

   FILE *printer;
{
   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('t', printer);
   fputc('3', printer);
   fputc('0', printer);
   fputc('0', printer);
   fputc('R', printer);

}




   /************************************************
   *
   *   print_bytes(...
   *
   ************************************************/

print_bytes(printer, buffer)
   FILE *printer;
   char buffer[];
{
   int        i;

   fputc(ESCAPE, printer);
   fputc('*', printer);
   fputc('b', printer);
   fputc('2', printer);
   fputc('0', printer);
   fputc('0', printer);
   fputc('W', printer);


   for(i=0; i<200; i++){
      fputc(buffer[i], printer);
   }
}  /* ends print_bytes */




   /**************************************************
   *
   *   print_original_200_row(...
   *
   ***************************************************/

print_original_200_row(printer, short_row)
   FILE  *printer;
   short short_row[200];
{
   char  row[8][200];
   char  c[200], response[80];
   int         i, j, k;
   short value;
   for(i=0; i<200; i++){
      value = short_row[i];
      if(value > 63) value = 63;
      if(value < 0)  value =  0;

      for(j=0; j<8; j++)
         row[j][i] = patterns[value][j];

   }  /* ends loop over i */

   for(i=0; i<8; i++){
      for(j=0; j<200; j++)
         c[j] = row[i][j];
      set_horizontal_offset(printer);
      print_bytes(printer, c);
   }  /* ends loop over i */

}  /* ends print_original_200_row */






   /***********************************
   *
   *   print_hist_image(...
   *
   ************************************/

print_hist_image(printer, hist)
   FILE *printer;
   unsigned long hist[];
{
   char   c, d;
   int          i, j, k;
   unsigned long limit, max;

   d = 0;
   c = 255;

      /********************************
      *
      *   First scale the histogram
      *
      *********************************/

   max = 0;
   for(i=0; i<256; i++)
      if(hist[i] > max) max = hist[i];

   if(max > 200){
      for(i=0; i<256; i++){
        hist[i] = (hist[i]*200)/max;
      }
   }


      /********************************
      *
      *   Second print it
      *
      *   Print a space between the image
      *   and the histogram.
      *
      *********************************/


   for(i=0; i<20; i++){
         end_graphics_mode(printer);
         select_300_dpi_resolution(printer);
         set_raster_width(printer);
         start_raster_graphics(printer);
         select_full_graphics_mode(printer);
         set_horizontal_offset(printer);
         fputc(ESCAPE, printer);
         fputc('*', printer);
         fputc('b', printer);
         fputc('2', printer);
         fputc('0', printer);
         fputc('0', printer);
         fputc('W', printer);

         for(j=0; j<200; j++)
            fputc(d, printer);
   }


   printf("\n\nHIST> Now printing the histogram");
   for(i=0; i<256; i++){
      printf("\n\tHIST> Histogram[%d]=%ld", 
            i, hist[i]);

            /* print the line 2 times */
      for(k=0; k<2; k++){

         end_graphics_mode(printer);
         select_300_dpi_resolution(printer);
         set_raster_width(printer);
         start_raster_graphics(printer);
         select_full_graphics_mode(printer);


            /***************************
            *
            *  Print grid marks every
            *  50 pixels.  Do this by
            *  setting a shorter margin
            *  then printing 2 marks then
            *  the data.
            *
            ****************************/

         if( (i ==   0) ||
             (i ==  50) ||
             (i == 100) ||
             (i == 150) ||
             (i == 200) ||
             (i == 255)){

            set_shorter_horizontal_offset(printer);
            fputc(ESCAPE, printer);
            fputc('*', printer);
            fputc('b', printer);
            fputc('2', printer);
            fputc('0', printer);
            fputc('2', printer);
            fputc('W', printer);

            fputc(c, printer);
            fputc(c, printer);


            if(hist[i] >= 200)
               hist[i] = 200;

            limit = 200 - hist[i];

            if(hist[i] == 0)
               fputc(c, printer);

            for(j=0; j<hist[i]; j++)
               fputc(c, printer);

            for(j=0; j<limit; j++)
              fputc(d, printer);

         }  /* ends print grid marks */


            /***************************
            *
            *  If you do not print
            *  grid marks, set the normal
            *  margin and then print the
            *  data.
            *
            ****************************/

         else{
            set_horizontal_offset(printer);
            /* this prints 200 bytes so print 200 */
            fputc(ESCAPE, printer);
            fputc('*', printer);
            fputc('b', printer);
            fputc('2', printer);
            fputc('0', printer);
            fputc('0', printer);
            fputc('W', printer);

            if(hist[i] >= 200)
               hist[i] = 200;

            limit = 200 - hist[i];

            if(hist[i] == 0)
               fputc(c, printer);

            for(j=0; j<hist[i]; j++)
               fputc(c, printer);

            for(j=0; j<limit; j++)
              fputc(d, printer);

         }  /* ends else no grid marks */

      }  /* ends loop over k */

   }  /* ends loop over i */

}  /* ends print_hist_image */