Move code for hOCR renderer to new file

Signed-off-by: Stefan Weil <sw@weilnetz.de>

Author: stweil

src/api/Makefile.am

@@ -32,7 +32,11 @@ libtesseract_api_la_CPPFLAGS = $(AM_CPPFLAGS)
 if VISIBILITY
 libtesseract_api_la_CPPFLAGS += -DTESS_EXPORTS
 endif
-libtesseract_api_la_SOURCES = baseapi.cpp capi.cpp renderer.cpp pdfrenderer.cpp altorenderer.cpp
+libtesseract_api_la_SOURCES = baseapi.cpp capi.cpp
+libtesseract_api_la_SOURCES += altorenderer.cpp
+libtesseract_api_la_SOURCES += hocrrenderer.cpp
+libtesseract_api_la_SOURCES += pdfrenderer.cpp
+libtesseract_api_la_SOURCES += renderer.cpp
 
 lib_LTLIBRARIES += libtesseract.la
 libtesseract_la_LDFLAGS = $(LEPTONICA_LIBS) $(OPENCL_LDFLAGS)

src/api/baseapi.cpp

@@ -1340,363 +1340,14 @@ char* TessBaseAPI::GetUTF8Text() {
   return result;
 }
 
-/**
- * Gets the block orientation at the current iterator position.
- */
-static tesseract::Orientation GetBlockTextOrientation(const PageIterator *it) {
-  tesseract::Orientation orientation;
-  tesseract::WritingDirection writing_direction;
-  tesseract::TextlineOrder textline_order;
-  float deskew_angle;
-  it->Orientation(&orientation, &writing_direction, &textline_order,
-                  &deskew_angle);
-  return orientation;
-}
-
-/**
- * Fits a line to the baseline at the given level, and appends its coefficients
- * to the hOCR string.
- * NOTE: The hOCR spec is unclear on how to specify baseline coefficients for
- * rotated textlines. For this reason, on textlines that are not upright, this
- * method currently only inserts a 'textangle' property to indicate the rotation
- * direction and does not add any baseline information to the hocr string.
- */
-static void AddBaselineCoordsTohOCR(const PageIterator *it,
-                                    PageIteratorLevel level,
-                                    STRING* hocr_str) {
-  tesseract::Orientation orientation = GetBlockTextOrientation(it);
-  if (orientation != ORIENTATION_PAGE_UP) {
-    hocr_str->add_str_int("; textangle ", 360 - orientation * 90);
-    return;
-  }
-
-  int left, top, right, bottom;
-  it->BoundingBox(level, &left, &top, &right, &bottom);
-
-  // Try to get the baseline coordinates at this level.
-  int x1, y1, x2, y2;
-  if (!it->Baseline(level, &x1, &y1, &x2, &y2))
-    return;
-  // Following the description of this field of the hOCR spec, we convert the
-  // baseline coordinates so that "the bottom left of the bounding box is the
-  // origin".
-  x1 -= left;
-  x2 -= left;
-  y1 -= bottom;
-  y2 -= bottom;
-
-  // Now fit a line through the points so we can extract coefficients for the
-  // equation:  y = p1 x + p0
-  double p1 = 0;
-  double p0 = 0;
-  if (x1 == x2) {
-    // Problem computing the polynomial coefficients.
-    return;
-  }
-  p1 = (y2 - y1) / static_cast<double>(x2 - x1);
-  p0 = y1 - static_cast<double>(p1 * x1);
-
-  hocr_str->add_str_double("; baseline ", round(p1 * 1000.0) / 1000.0);
-  hocr_str->add_str_double(" ", round(p0 * 1000.0) / 1000.0);
-}
-
-static void AddIdTohOCR(STRING* hocr_str, const std::string base, int num1,
-                        int num2) {
-  const size_t BUFSIZE = 64;
-  char id_buffer[BUFSIZE];
-  if (num2 >= 0) {
-    snprintf(id_buffer, BUFSIZE - 1, "%s_%d_%d", base.c_str(), num1, num2);
-  } else {
-    snprintf(id_buffer, BUFSIZE - 1, "%s_%d", base.c_str(), num1);
-  }
-  id_buffer[BUFSIZE - 1] = '\0';
-  *hocr_str += " id='";
-  *hocr_str += id_buffer;
-  *hocr_str += "'";
-}
-
-static void AddIdTohOCR(STRING* hocr_str, const std::string base, int num1,
-  int num2, int num3) {
-  const size_t BUFSIZE = 64;
-  char id_buffer[BUFSIZE];
-  snprintf(id_buffer, BUFSIZE - 1, "%s_%d_%d_%d", base.c_str(), num1, num2,num3);
-  id_buffer[BUFSIZE - 1] = '\0';
-  *hocr_str += " id='";
-  *hocr_str += id_buffer;
-  *hocr_str += "'";
-}
-
-static void AddBoxTohOCR(const ResultIterator* it, PageIteratorLevel level,
-                         STRING* hocr_str) {
-  int left, top, right, bottom;
-  it->BoundingBox(level, &left, &top, &right, &bottom);
-  // This is the only place we use double quotes instead of single quotes,
-  // but it may too late to change for consistency
-  hocr_str->add_str_int(" title=\"bbox ", left);
-  hocr_str->add_str_int(" ", top);
-  hocr_str->add_str_int(" ", right);
-  hocr_str->add_str_int(" ", bottom);
-  // Add baseline coordinates & heights for textlines only.
-  if (level == RIL_TEXTLINE) {
-    AddBaselineCoordsTohOCR(it, level, hocr_str);
-    // add custom height measures
-    float row_height, descenders, ascenders;  // row attributes
-    it->RowAttributes(&row_height, &descenders, &ascenders);
-    // TODO(rays): Do we want to limit these to a single decimal place?
-    hocr_str->add_str_double("; x_size ", row_height);
-    hocr_str->add_str_double("; x_descenders ", descenders * -1);
-    hocr_str->add_str_double("; x_ascenders ", ascenders);
-  }
-  *hocr_str += "\">";
-}
-
 static void AddBoxToTSV(const PageIterator* it, PageIteratorLevel level,
-                        STRING* hocr_str) {
+                        STRING* text) {
   int left, top, right, bottom;
   it->BoundingBox(level, &left, &top, &right, &bottom);
-  hocr_str->add_str_int("\t", left);
-  hocr_str->add_str_int("\t", top);
-  hocr_str->add_str_int("\t", right - left);
-  hocr_str->add_str_int("\t", bottom - top);
-}
-
-/**
- * Make a HTML-formatted string with hOCR markup from the internal
- * data structures.
- * page_number is 0-based but will appear in the output as 1-based.
- * Image name/input_file_ can be set by SetInputName before calling
- * GetHOCRText
- * STL removed from original patch submission and refactored by rays.
- * Returned string must be freed with the delete [] operator.
- */
-char* TessBaseAPI::GetHOCRText(int page_number) {
-  return GetHOCRText(nullptr, page_number);
-}
-
-/**
- * Make a HTML-formatted string with hOCR markup from the internal
- * data structures.
- * page_number is 0-based but will appear in the output as 1-based.
- * Image name/input_file_ can be set by SetInputName before calling
- * GetHOCRText
- * STL removed from original patch submission and refactored by rays.
- * Returned string must be freed with the delete [] operator.
- */
-char* TessBaseAPI::GetHOCRText(ETEXT_DESC* monitor, int page_number) {
-  if (tesseract_ == nullptr || (page_res_ == nullptr && Recognize(monitor) < 0))
-    return nullptr;
-
-  int lcnt = 1, bcnt = 1, pcnt = 1, wcnt = 1, tcnt = 1, gcnt = 1;
-  int page_id = page_number + 1;  // hOCR uses 1-based page numbers.
-  bool para_is_ltr = true;        // Default direction is LTR
-  const char* paragraph_lang = nullptr;
-  bool font_info = false;
-  GetBoolVariable("hocr_font_info", &font_info);
-
-  STRING hocr_str("");
-
-  if (input_file_ == nullptr)
-      SetInputName(nullptr);
-
-#ifdef _WIN32
-  // convert input name from ANSI encoding to utf-8
-  int str16_len =
-      MultiByteToWideChar(CP_ACP, 0, input_file_->string(), -1, nullptr, 0);
-  wchar_t *uni16_str = new WCHAR[str16_len];
-  str16_len = MultiByteToWideChar(CP_ACP, 0, input_file_->string(), -1,
-                                  uni16_str, str16_len);
-  int utf8_len = WideCharToMultiByte(CP_UTF8, 0, uni16_str, str16_len, nullptr, 0,
-                                     nullptr, nullptr);
-  char *utf8_str = new char[utf8_len];
-  WideCharToMultiByte(CP_UTF8, 0, uni16_str, str16_len, utf8_str,
-                      utf8_len, nullptr, nullptr);
-  *input_file_ = utf8_str;
-  delete[] uni16_str;
-  delete[] utf8_str;
-#endif
-
-  hocr_str += "  <div class='ocr_page'";
-  AddIdTohOCR(&hocr_str, "page", page_id, -1);
-  hocr_str += " title='image \"";
-  if (input_file_) {
-    hocr_str += HOcrEscape(input_file_->string());
-  } else {
-    hocr_str += "unknown";
-  }
-  hocr_str.add_str_int("\"; bbox ", rect_left_);
-  hocr_str.add_str_int(" ", rect_top_);
-  hocr_str.add_str_int(" ", rect_width_);
-  hocr_str.add_str_int(" ", rect_height_);
-  hocr_str.add_str_int("; ppageno ", page_number);
-  hocr_str += "'>\n";
-
-  ResultIterator *res_it = GetIterator();
-  while (!res_it->Empty(RIL_BLOCK)) {
-    if (res_it->Empty(RIL_WORD)) {
-      res_it->Next(RIL_WORD);
-      continue;
-    }
-
-    // Open any new block/paragraph/textline.
-    if (res_it->IsAtBeginningOf(RIL_BLOCK)) {
-      para_is_ltr = true;  // reset to default direction
-      hocr_str += "   <div class='ocr_carea'";
-      AddIdTohOCR(&hocr_str, "block", page_id, bcnt);
-      AddBoxTohOCR(res_it, RIL_BLOCK, &hocr_str);
-    }
-    if (res_it->IsAtBeginningOf(RIL_PARA)) {
-      hocr_str += "\n    <p class='ocr_par'";
-      para_is_ltr = res_it->ParagraphIsLtr();
-      if (!para_is_ltr) {
-        hocr_str += " dir='rtl'";
-      }
-      AddIdTohOCR(&hocr_str, "par", page_id, pcnt);
-      paragraph_lang = res_it->WordRecognitionLanguage();
-      if (paragraph_lang) {
-        hocr_str += " lang='";
-        hocr_str += paragraph_lang;
-        hocr_str += "'";
-      }
-      AddBoxTohOCR(res_it, RIL_PARA, &hocr_str);
-    }
-    if (res_it->IsAtBeginningOf(RIL_TEXTLINE)) {
-      hocr_str += "\n     <span class='ocr_line'";
-      AddIdTohOCR(&hocr_str, "line", page_id, lcnt);
-      AddBoxTohOCR(res_it, RIL_TEXTLINE, &hocr_str);
-    }
-
-    // Now, process the word...
-    std::vector<std::vector<std::pair<const char*, float>>>* confidencemap = nullptr;
-    if (tesseract_->lstm_choice_mode) {
-      confidencemap = res_it->GetBestLSTMSymbolChoices();
-    }
-    hocr_str += "\n      <span class='ocrx_word'";
-    AddIdTohOCR(&hocr_str, "word", page_id, wcnt);
-    int left, top, right, bottom;
-    bool bold, italic, underlined, monospace, serif, smallcaps;
-    int pointsize, font_id;
-    const char *font_name;
-    res_it->BoundingBox(RIL_WORD, &left, &top, &right, &bottom);
-    font_name = res_it->WordFontAttributes(&bold, &italic, &underlined,
-                                           &monospace, &serif, &smallcaps,
-                                           &pointsize, &font_id);
-    hocr_str.add_str_int(" title='bbox ", left);
-    hocr_str.add_str_int(" ", top);
-    hocr_str.add_str_int(" ", right);
-    hocr_str.add_str_int(" ", bottom);
-    hocr_str.add_str_int("; x_wconf ", res_it->Confidence(RIL_WORD));
-    if (font_info) {
-      if (font_name) {
-        hocr_str += "; x_font ";
-        hocr_str += HOcrEscape(font_name);
-      }
-      hocr_str.add_str_int("; x_fsize ", pointsize);
-    }
-    hocr_str += "'";
-    const char* lang = res_it->WordRecognitionLanguage();
-    if (lang && (!paragraph_lang || strcmp(lang, paragraph_lang))) {
-      hocr_str += " lang='";
-      hocr_str += lang;
-      hocr_str += "'";
-    }
-    switch (res_it->WordDirection()) {
-      // Only emit direction if different from current paragraph direction
-      case DIR_LEFT_TO_RIGHT:
-        if (!para_is_ltr) hocr_str += " dir='ltr'";
-        break;
-      case DIR_RIGHT_TO_LEFT:
-        if (para_is_ltr) hocr_str += " dir='rtl'";
-        break;
-      case DIR_MIX:
-      case DIR_NEUTRAL:
-      default:  // Do nothing.
-        break;
-    }
-    hocr_str += ">";
-    bool last_word_in_line = res_it->IsAtFinalElement(RIL_TEXTLINE, RIL_WORD);
-    bool last_word_in_para = res_it->IsAtFinalElement(RIL_PARA, RIL_WORD);
-    bool last_word_in_block = res_it->IsAtFinalElement(RIL_BLOCK, RIL_WORD);
-    if (bold) hocr_str += "<strong>";
-    if (italic) hocr_str += "<em>";
-    do {
-      const std::unique_ptr<const char[]> grapheme(
-          res_it->GetUTF8Text(RIL_SYMBOL));
-      if (grapheme && grapheme[0] != 0) {
-        hocr_str += HOcrEscape(grapheme.get());
-      }
-      res_it->Next(RIL_SYMBOL);
-    } while (!res_it->Empty(RIL_BLOCK) && !res_it->IsAtBeginningOf(RIL_WORD));
-    if (italic) hocr_str += "</em>";
-    if (bold) hocr_str += "</strong>";
-    // If the lstm choice mode is required it is added here
-    if (tesseract_->lstm_choice_mode == 1 && confidencemap != nullptr) {
-      for (size_t i = 0; i < confidencemap->size(); i++) {
-        hocr_str += "\n       <span class='ocrx_cinfo'";
-        AddIdTohOCR(&hocr_str, "timestep", page_id, wcnt, tcnt);
-        hocr_str += ">";
-        std::vector<std::pair<const char*, float>> timestep = (*confidencemap)[i];
-        for (std::pair<const char*, float> conf : timestep) {
-          hocr_str += "<span class='ocr_glyph'";
-          AddIdTohOCR(&hocr_str, "choice", page_id, wcnt, gcnt);
-          hocr_str.add_str_int(" title='x_confs ", int(conf.second * 100));
-          hocr_str += "'";
-          hocr_str += ">";
-          hocr_str += conf.first;
-          hocr_str += "</span>";
-          gcnt++;
-        }
-        hocr_str += "</span>";
-        tcnt++;
-      }
-    } else if (tesseract_->lstm_choice_mode == 2 && confidencemap != nullptr) {
-      for (size_t i = 0; i < confidencemap->size(); i++) {
-        std::vector<std::pair<const char*, float>> timestep = (*confidencemap)[i];
-        if (timestep.size() > 0) {
-          hocr_str += "\n       <span class='ocrx_cinfo'";
-          AddIdTohOCR(&hocr_str, "lstm_choices", page_id, wcnt, tcnt);
-          hocr_str += " chosen='";
-          hocr_str += timestep[0].first;
-          hocr_str += "'>";
-          for (size_t j = 1; j < timestep.size(); j++) {
-            hocr_str += "<span class='ocr_glyph'";
-            AddIdTohOCR(&hocr_str, "choice", page_id, wcnt, gcnt);
-            hocr_str.add_str_int(" title='x_confs ", int(timestep[j].second * 100));
-            hocr_str += "'";
-            hocr_str += ">";
-            hocr_str += timestep[j].first;
-            hocr_str += "</span>";
-            gcnt++;
-          }
-          hocr_str += "</span>";
-          tcnt++;
-        }
-      }
-    }
-    hocr_str += "</span>";
-    tcnt = 1;
-    gcnt = 1;
-    wcnt++;
-    // Close any ending block/paragraph/textline.
-    if (last_word_in_line) {
-      hocr_str += "\n     </span>";
-      lcnt++;
-    }
-    if (last_word_in_para) {
-      hocr_str += "\n    </p>\n";
-      pcnt++;
-      para_is_ltr = true;  // back to default direction
-    }
-    if (last_word_in_block) {
-      hocr_str += "   </div>\n";
-      bcnt++;
-    }
-  }
-  hocr_str += "  </div>\n";
-
-  char *ret = new char[hocr_str.length() + 1];
-  strcpy(ret, hocr_str.string());
-  delete res_it;
-  return ret;
+  text->add_str_int("\t", left);
+  text->add_str_int("\t", top);
+  text->add_str_int("\t", right - left);
+  text->add_str_int("\t", bottom - top);
 }
 
 /**