preserve interword spaces patch - Issue 1409

Author: zdenop

ccmain/resultiterator.cpp

@@ -34,6 +34,12 @@ ResultIterator::ResultIterator(const LTRResultIterator &resit)
     : LTRResultIterator(resit) {
   in_minor_direction_ = false;
   at_beginning_of_minor_run_ = false;
+
+  BoolParam *p = ParamUtils::FindParam<BoolParam>(
+    "preserve_interword_spaces", GlobalParams()->bool_params,
+    tesseract_->params()->bool_params);
+  if (p != NULL) preserve_interword_spaces_ = (bool)(*p);
+
   current_paragraph_is_ltr_ = CurrentParagraphIsLtr();
   MoveToLogicalStartOfTextline();
 }
@@ -629,14 +635,16 @@ void ResultIterator::IterateAndAppendUTF8TextlineText(STRING *text) {
 
   int words_appended = 0;
   do {
+    int numSpaces = preserve_interword_spaces_ ? it_->word()->word->space() : 1;
+    for(int i = 0 ; i < numSpaces ; ++i) {
+      *text += " ";
+    }
     AppendUTF8WordText(text);
     words_appended++;
-    *text += " ";
   } while (Next(RIL_WORD) && !IsAtBeginningOf(RIL_TEXTLINE));
   if (BidiDebug(1)) {
     tprintf("%d words printed\n", words_appended);
   }
-  text->truncate_at(text->length() - 1);
   *text += line_separator_;
   // If we just finished a paragraph, add an extra newline.
   if (it_->block() == NULL || IsAtBeginningOf(RIL_PARA))

ccmain/resultiterator.h

@@ -46,8 +46,8 @@ class TESS_API ResultIterator : public LTRResultIterator {
   virtual ~ResultIterator() {}
 
   // ============= Moving around within the page ============.
-  /** 
-   * Moves the iterator to point to the start of the page to begin 
+  /**
+   * Moves the iterator to point to the start of the page to begin
    * an iteration.
    */
   virtual void Begin();
@@ -181,7 +181,7 @@ class TESS_API ResultIterator : public LTRResultIterator {
   void MoveToLogicalStartOfTextline();
 
   /**
-   * Precondition: current_paragraph_is_ltr_ and in_minor_direction_ 
+   * Precondition: current_paragraph_is_ltr_ and in_minor_direction_
    * are set.
    */
   void MoveToLogicalStartOfWord();
@@ -231,6 +231,12 @@ class TESS_API ResultIterator : public LTRResultIterator {
 
   /** Is the currently pointed-at character in a minor-direction sequence? */
   bool in_minor_direction_;
+
+  /**
+   * Should detected inter-word spaces be preserved, or "compressed" to a single
+   * space character (default behavior).
+   */
+  bool preserve_interword_spaces_ = false;
 };
 
 }  // namespace tesseract.

ccmain/tesseractclass.cpp

@@ -440,6 +440,8 @@ Tesseract::Tesseract()
                   this->params()),
     INT_MEMBER(tessedit_parallelize, 0, "Run in parallel where possible",
                 this->params()),
+    BOOL_MEMBER(preserve_interword_spaces, false,
+                "Preserve multiple interword spaces", this->params()),
 
     // The following parameters were deprecated and removed from their original
     // locations. The parameters are temporarily kept here to give Tesseract

ccmain/tesseractclass.h

@@ -1009,6 +1009,7 @@ class Tesseract : public Wordrec {
   double_VAR_H(textord_tabfind_aligned_gap_fraction, 0.75,
                "Fraction of height used as a minimum gap for aligned blobs.");
   INT_VAR_H(tessedit_parallelize, 0, "Run in parallel where possible");
+  BOOL_VAR_H(preserve_interword_spaces, false, "Preserve multiple interword spaces");
 
   // The following parameters were deprecated and removed from their original
   // locations. The parameters are temporarily kept here to give Tesseract