Add characters to a training file.

The operator append_ocr_trainf serves to prepare the training with the operator trainf_ocr_class_box. Hereby regions, representing characters, including their gray values (region and pixel) and the corresponding class name will be written into a file. An arbitrary number of regions within one image is supported. For each character (region) in Character the corresponding class name must be specified in Class. The gray values are passed via the parameter Image. In contrast to the operator write_ocr_trainf the characters are appended to an existing file using the same training file format as this file. If the file does not exist, a new file is generated. In this case, the file format can be chosen by the parameter 'ocr_trainf_version' of the operator set_system. If no file extension is specified in FileName, the extension '.trf' is appended to the name.

char       name[128];
char       class[128];

read_image(&Image,"character.tiff");
bin_threshold(Image,&Dark);
connection(Dark,&Character);
count_obj(Character,&num);
create_tuple(&Class,num);
open_window(0,0,-1,-1,0,"","",&WindowHandle);
set_color(WindowHandle,"red");
for (i=0; i<num; i++) {
  select_obj(Character,&SingleCharacter,i);
  clear_window(WindowHandle);
  disp_region(SingleCharacter,WindowHandle);
  printf("class of character %d ?\n",i);
  scanf("%s\n",class);
  append_ocr_trainf(Character,Image,name,class);
}

If the parameters are correct, the operator append_ocr_trainf returns the value 2 (H_MSG_TRUE). Otherwise an exception will be raised.

append_ocr_trainf is processed under mutual exclusion against itself and without parallelization.

threshold, connection, create_ocr_class_box, read_ocr

trainf_ocr_class_box, info_ocr_class_box, write_ocr, do_ocr_multi, do_ocr_single

write_ocr_trainf, write_ocr_trainf_image

OCR/OCV