Function ReadNextBox

deps/tesseract/ccstruct/boxread.cpp:119–122

TODO(rays) convert all uses of ReadNextBox to use the new ReadAllBoxes. Box files are used ONLY DURING TRAINING, but by both processes of creating tr files with tesseract, and unicharset_extractor. ReadNextBox factors out the code to interpret a line of a box file so that applybox and unicharset_extractor interpret the same way. This function returns the next valid box file utf8 string and coords

// utf8_str is set with the unichar string, and bounding box with the box.
// If there are page numbers in the file, it reads them all.
bool ReadNextBox(int *line_number, FILE* box_file,
                 STRING* utf8_str, TBOX* bounding_box) {
  return ReadNextBox(-1, line_number, box_file, utf8_str, bounding_box);
}

// As ReadNextBox above, but get a specific page number. (0-based)
// Use -1 to read any page number. Files without page number all