--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/tesseract/src/api/hocrrenderer.cpp	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,524 @@
+/**********************************************************************
+ * File:        hocrrenderer.cpp
+ * Description: Simple API for calling tesseract.
+ * Author:      Ray Smith (original code from baseapi.cpp)
+ * Author:      Stefan Weil (moved to separate file and cleaned code)
+ *
+ * (C) Copyright 2006, Google Inc.
+ ** Licensed under the Apache License, Version 2.0 (the "License");
+ ** you may not use this file except in compliance with the License.
+ ** You may obtain a copy of the License at
+ ** http://www.apache.org/licenses/LICENSE-2.0
+ ** Unless required by applicable law or agreed to in writing, software
+ ** distributed under the License is distributed on an "AS IS" BASIS,
+ ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ ** See the License for the specific language governing permissions and
+ ** limitations under the License.
+ *
+ **********************************************************************/
+
+#include <tesseract/baseapi.h> // for TessBaseAPI
+#include <locale>              // for std::locale::classic
+#include <memory>              // for std::unique_ptr
+#include <sstream>             // for std::stringstream
+#include <tesseract/renderer.h>
+#include "helpers.h"        // for copy_string
+#include "tesseractclass.h" // for Tesseract
+
+namespace tesseract {
+
+/**
+ * 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,
+                                    std::stringstream &hocr_str) {
+  tesseract::Orientation orientation = GetBlockTextOrientation(it);
+  if (orientation != ORIENTATION_PAGE_UP) {
+    hocr_str << "; 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
+  if (x1 == x2) {
+    // Problem computing the polynomial coefficients.
+    return;
+  }
+  double p1 = (y2 - y1) / static_cast<double>(x2 - x1);
+  double p0 = y1 - p1 * x1;
+
+  hocr_str << "; baseline " << round(p1 * 1000.0) / 1000.0 << " "
+           << round(p0 * 1000.0) / 1000.0;
+}
+
+static void AddBoxTohOCR(const ResultIterator *it, PageIteratorLevel level,
+                         std::stringstream &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 << " title=\"bbox " << left << " " << top << " " << right << " "
+           << 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 << "; x_size " << row_height << "; x_descenders " << -descenders
+             << "; x_ascenders " << ascenders;
+  }
+  hocr_str << "\">";
+}
+
+/**
+ * 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, scnt = 1, tcnt = 1, ccnt = 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;
+  bool hocr_boxes = false;
+  GetBoolVariable("hocr_font_info", &font_info);
+  GetBoolVariable("hocr_char_boxes", &hocr_boxes);
+
+  if (input_file_.empty()) {
+    SetInputName(nullptr);
+  }
+
+  std::stringstream hocr_str;
+  // Use "C" locale (needed for double values x_size and x_descenders).
+  hocr_str.imbue(std::locale::classic());
+  // Use 8 digits for double values.
+  hocr_str.precision(8);
+  hocr_str << "  <div class='ocr_page'"
+           << " id='"
+           << "page_" << page_id << "'"
+           << " title='image \"";
+  if (!input_file_.empty()) {
+    hocr_str << HOcrEscape(input_file_.c_str());
+  } else {
+    hocr_str << "unknown";
+  }
+
+  hocr_str << "\"; bbox " << rect_left_ << " " << rect_top_ << " "
+           << rect_width_ << " " << rect_height_ << "; ppageno " << page_number
+           << "; scan_res " << GetSourceYResolution() << " "
+           << GetSourceYResolution() << "'>\n";
+
+  std::unique_ptr<ResultIterator> res_it(GetIterator());
+  while (!res_it->Empty(RIL_BLOCK)) {
+    int left, top, right, bottom;
+    auto block_type = res_it->BlockType();
+    switch (block_type) {
+      case PT_FLOWING_IMAGE:
+      case PT_HEADING_IMAGE:
+      case PT_PULLOUT_IMAGE: {
+        // Handle all kinds of images.
+        res_it.get()->BoundingBox(RIL_TEXTLINE, &left, &top, &right, &bottom);
+        hocr_str << "   <div class='ocr_photo' id='block_" << page_id << '_'
+                 << bcnt++ << "' title=\"bbox " << left << " " << top << " "
+                 << right << " " << bottom << "\"></div>\n";
+        res_it->Next(RIL_BLOCK);
+        continue;
+      }
+      case PT_HORZ_LINE:
+      case PT_VERT_LINE:
+        // Handle horizontal and vertical lines.
+        res_it.get()->BoundingBox(RIL_TEXTLINE, &left, &top, &right, &bottom);
+        hocr_str << "   <div class='ocr_separator' id='block_" << page_id << '_'
+                 << bcnt++ << "' title=\"bbox " << left << " " << top << " "
+                 << right << " " << bottom << "\"></div>\n";
+        res_it->Next(RIL_BLOCK);
+        continue;
+      case PT_NOISE:
+        tprintf("TODO: Please report image which triggers the noise case.\n");
+        ASSERT_HOST(false);
+      default:
+        break;
+    }
+
+    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'"
+               << " id='"
+               << "block_" << page_id << "_" << bcnt << "'";
+      AddBoxTohOCR(res_it.get(), 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'";
+      }
+      hocr_str << " id='"
+               << "par_" << page_id << "_" << pcnt << "'";
+      paragraph_lang = res_it->WordRecognitionLanguage();
+      if (paragraph_lang) {
+        hocr_str << " lang='" << paragraph_lang << "'";
+      }
+      AddBoxTohOCR(res_it.get(), RIL_PARA, hocr_str);
+    }
+    if (res_it->IsAtBeginningOf(RIL_TEXTLINE)) {
+      hocr_str << "\n     <span class='";
+      switch (block_type) {
+        case PT_HEADING_TEXT:
+          hocr_str << "ocr_header";
+          break;
+        case PT_PULLOUT_TEXT:
+          hocr_str << "ocr_textfloat";
+          break;
+        case PT_CAPTION_TEXT:
+          hocr_str << "ocr_caption";
+          break;
+        case PT_FLOWING_IMAGE:
+        case PT_HEADING_IMAGE:
+        case PT_PULLOUT_IMAGE:
+          ASSERT_HOST(false);
+          break;
+        default:
+          hocr_str << "ocr_line";
+      }
+      hocr_str << "' id='"
+               << "line_" << page_id << "_" << lcnt << "'";
+      AddBoxTohOCR(res_it.get(), RIL_TEXTLINE, hocr_str);
+    }
+
+    // Now, process the word...
+    int32_t lstm_choice_mode = tesseract_->lstm_choice_mode;
+    std::vector<std::vector<std::vector<std::pair<const char *, float>>>>
+        *rawTimestepMap = nullptr;
+    std::vector<std::vector<std::pair<const char *, float>>> *CTCMap = nullptr;
+    if (lstm_choice_mode) {
+      CTCMap = res_it->GetBestLSTMSymbolChoices();
+      rawTimestepMap = res_it->GetRawLSTMTimesteps();
+    }
+    hocr_str << "\n      <span class='ocrx_word'"
+             << " id='"
+             << "word_" << page_id << "_" << wcnt << "'";
+    bool bold, italic, underlined, monospace, serif, smallcaps;
+    int pointsize, font_id;
+    res_it->BoundingBox(RIL_WORD, &left, &top, &right, &bottom);
+    const char *font_name =
+        res_it->WordFontAttributes(&bold, &italic, &underlined, &monospace,
+                                   &serif, &smallcaps, &pointsize, &font_id);
+    hocr_str << " title='bbox " << left << " " << top << " " << right << " "
+             << bottom << "; x_wconf "
+             << static_cast<int>(res_it->Confidence(RIL_WORD));
+    if (font_info) {
+      if (font_name) {
+        hocr_str << "; x_font " << HOcrEscape(font_name).c_str();
+      }
+      hocr_str << "; x_fsize " << pointsize;
+    }
+    hocr_str << "'";
+    const char *lang = res_it->WordRecognitionLanguage();
+    if (lang && (!paragraph_lang || strcmp(lang, paragraph_lang))) {
+      hocr_str << " lang='" << lang << "'";
+    }
+    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) {
+        if (hocr_boxes) {
+          res_it->BoundingBox(RIL_SYMBOL, &left, &top, &right, &bottom);
+          hocr_str << "\n       <span class='ocrx_cinfo' title='x_bboxes "
+                   << left << " " << top << " " << right << " " << bottom
+                   << "; x_conf " << res_it->Confidence(RIL_SYMBOL) << "'>";
+        }
+        hocr_str << HOcrEscape(grapheme.get()).c_str();
+        if (hocr_boxes) {
+          hocr_str << "</span>";
+          tesseract::ChoiceIterator ci(*res_it);
+          if (lstm_choice_mode == 1 && ci.Timesteps() != nullptr) {
+            std::vector<std::vector<std::pair<const char *, float>>> *symbol =
+                ci.Timesteps();
+            hocr_str << "\n        <span class='ocr_symbol'"
+                     << " id='"
+                     << "symbol_" << page_id << "_" << wcnt << "_" << scnt
+                     << "'>";
+            for (const auto &timestep : *symbol) {
+              hocr_str << "\n         <span class='ocrx_cinfo'"
+                       << " id='"
+                       << "timestep" << page_id << "_" << wcnt << "_" << tcnt
+                       << "'>";
+              for (auto conf : timestep) {
+                hocr_str << "\n          <span class='ocrx_cinfo'"
+                         << " id='"
+                         << "choice_" << page_id << "_" << wcnt << "_" << ccnt
+                         << "'"
+                         << " title='x_confs " << int(conf.second * 100) << "'>"
+                         << HOcrEscape(conf.first).c_str() << "</span>";
+                ++ccnt;
+              }
+              hocr_str << "</span>";
+              ++tcnt;
+            }
+            hocr_str << "\n        </span>";
+            ++scnt;
+          } else if (lstm_choice_mode == 2) {
+            hocr_str << "\n        <span class='ocrx_cinfo'"
+                     << " id='"
+                     << "lstm_choices_" << page_id << "_" << wcnt << "_" << tcnt
+                     << "'>";
+            do {
+              const char *choice = ci.GetUTF8Text();
+              float choiceconf = ci.Confidence();
+              if (choice != nullptr) {
+                hocr_str << "\n         <span class='ocrx_cinfo'"
+                         << " id='"
+                         << "choice_" << page_id << "_" << wcnt << "_" << ccnt
+                         << "'"
+                         << " title='x_confs " << choiceconf << "'>"
+                         << HOcrEscape(choice).c_str() << "</span>";
+                ccnt++;
+              }
+            } while (ci.Next());
+            hocr_str << "\n        </span>";
+            tcnt++;
+          }
+        }
+      }
+      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 (lstm_choice_mode == 1 && !hocr_boxes && rawTimestepMap != nullptr) {
+      for (const auto &symbol : *rawTimestepMap) {
+        hocr_str << "\n       <span class='ocr_symbol'"
+                 << " id='"
+                 << "symbol_" << page_id << "_" << wcnt << "_" << scnt << "'>";
+        for (const auto &timestep : symbol) {
+          hocr_str << "\n        <span class='ocrx_cinfo'"
+                   << " id='"
+                   << "timestep" << page_id << "_" << wcnt << "_" << tcnt
+                   << "'>";
+          for (auto &&conf : timestep) {
+            hocr_str << "\n         <span class='ocrx_cinfo'"
+                     << " id='"
+                     << "choice_" << page_id << "_" << wcnt << "_" << ccnt
+                     << "'"
+                     << " title='x_confs " << int(conf.second * 100) << "'>"
+                     << HOcrEscape(conf.first).c_str() << "</span>";
+            ++ccnt;
+          }
+          hocr_str << "</span>";
+          ++tcnt;
+        }
+        hocr_str << "</span>";
+        ++scnt;
+      }
+    } else if (lstm_choice_mode == 2 && !hocr_boxes && CTCMap != nullptr) {
+      for (const auto &timestep : *CTCMap) {
+        if (timestep.size() > 0) {
+          hocr_str << "\n       <span class='ocrx_cinfo'"
+                   << " id='"
+                   << "lstm_choices_" << page_id << "_" << wcnt << "_" << tcnt
+                   << "'>";
+          for (auto &j : timestep) {
+            float conf = 100 - tesseract_->lstm_rating_coefficient * j.second;
+            if (conf < 0.0f) {
+              conf = 0.0f;
+            }
+            if (conf > 100.0f) {
+              conf = 100.0f;
+            }
+            hocr_str << "\n        <span class='ocrx_cinfo'"
+                     << " id='"
+                     << "choice_" << page_id << "_" << wcnt << "_" << ccnt
+                     << "'"
+                     << " title='x_confs " << conf << "'>"
+                     << HOcrEscape(j.first).c_str() << "</span>";
+            ccnt++;
+          }
+          hocr_str << "</span>";
+          tcnt++;
+        }
+      }
+    }
+    // Close ocrx_word.
+    if (hocr_boxes || lstm_choice_mode > 0) {
+      hocr_str << "\n      ";
+    }
+    hocr_str << "</span>";
+    tcnt = 1;
+    ccnt = 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";
+
+  return copy_string(hocr_str.str());
+}
+
+/**********************************************************************
+ * HOcr Text Renderer interface implementation
+ **********************************************************************/
+TessHOcrRenderer::TessHOcrRenderer(const char *outputbase)
+    : TessResultRenderer(outputbase, "hocr") {
+  font_info_ = false;
+}
+
+TessHOcrRenderer::TessHOcrRenderer(const char *outputbase, bool font_info)
+    : TessResultRenderer(outputbase, "hocr") {
+  font_info_ = font_info;
+}
+
+bool TessHOcrRenderer::BeginDocumentHandler() {
+  AppendString(
+      "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
+      "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\"\n"
+      "    \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n"
+      "<html xmlns=\"http://www.w3.org/1999/xhtml\" xml:lang=\"en\" "
+      "lang=\"en\">\n <head>\n  <title>");
+  AppendString(title());
+  AppendString(
+      "</title>\n"
+      "  <meta http-equiv=\"Content-Type\" content=\"text/html;"
+      "charset=utf-8\"/>\n"
+      "  <meta name='ocr-system' content='tesseract " TESSERACT_VERSION_STR
+      "' />\n"
+      "  <meta name='ocr-capabilities' content='ocr_page ocr_carea ocr_par"
+      " ocr_line ocrx_word ocrp_dir ocrp_lang ocrp_wconf");
+  if (font_info_) {
+    AppendString(" ocrp_font ocrp_fsize");
+  }
+  AppendString(
+      "'/>\n"
+      " </head>\n"
+      " <body>\n");
+
+  return true;
+}
+
+bool TessHOcrRenderer::EndDocumentHandler() {
+  AppendString(" </body>\n</html>\n");
+
+  return true;
+}
+
+bool TessHOcrRenderer::AddImageHandler(TessBaseAPI *api) {
+  const std::unique_ptr<const char[]> hocr(api->GetHOCRText(imagenum()));
+  if (hocr == nullptr) {
+    return false;
+  }
+
+  AppendString(hocr.get());
+
+  return true;
+}
+
+} // namespace tesseract