Added JPEG quality option parameter (-c jpg_quality=n)

api/capi.cpp

@@ -65,9 +65,9 @@ TESS_API TessResultRenderer* TESS_CALL TessHOcrRendererCreate2(const char* outpu
 }
 
 TESS_API TessResultRenderer* TESS_CALL TessPDFRendererCreate(const char* outputbase, const char* datadir,
-                                                             BOOL textonly)
+                                                             BOOL textonly, int jpg_quality)
 {
-    return new TessPDFRenderer(outputbase, datadir, textonly);
+    return new TessPDFRenderer(outputbase, datadir, textonly, jpg_quality);
 }
 
 TESS_API TessResultRenderer* TESS_CALL TessUnlvRendererCreate(const char* outputbase)

api/capi.h

@@ -120,7 +120,7 @@ TESS_API TessResultRenderer* TESS_CALL TessTextRendererCreate(const char* output
 TESS_API TessResultRenderer* TESS_CALL TessHOcrRendererCreate(const char* outputbase);
 TESS_API TessResultRenderer* TESS_CALL TessHOcrRendererCreate2(const char* outputbase, BOOL font_info);
 TESS_API TessResultRenderer* TESS_CALL TessPDFRendererCreate(const char* outputbase, const char* datadir,
-                                                             BOOL textonly);
+                                                             BOOL textonly, int jpg_quality);
 TESS_API TessResultRenderer* TESS_CALL TessUnlvRendererCreate(const char* outputbase);
 TESS_API TessResultRenderer* TESS_CALL TessBoxTextRendererCreate(const char* outputbase);
 

api/pdfrenderer.cpp

@@ -181,11 +181,12 @@ static const int kMaxBytesPerCodepoint = 20;
  **********************************************************************/
 
 TessPDFRenderer::TessPDFRenderer(const char *outputbase, const char *datadir,
-                                 bool textonly)
+                                 bool textonly, int jpg_quality)
     : TessResultRenderer(outputbase, "pdf") {
   obj_  = 0;
   datadir_ = datadir;
   textonly_ = textonly;
+  jpg_quality_ = jpg_quality;
   offsets_.push_back(0);
 }
 
@@ -695,7 +696,7 @@ bool TessPDFRenderer::imageToPDFObj(Pix *pix,
                                     char *filename,
                                     long int objnum,
                                     char **pdf_object,
-                                    long int *pdf_object_size) {
+                                    long int *pdf_object_size, int jpg_quality) {
   size_t n;
   char b0[kBasicBufSize];
   char b1[kBasicBufSize];
@@ -708,8 +709,7 @@ bool TessPDFRenderer::imageToPDFObj(Pix *pix,
     return false;
 
   L_Compressed_Data *cid = NULL;
-  const int kJpegQuality = 85;
+  const int kJpegQuality = jpg_quality;
-
   int format, sad;
   findFileFormat(filename, &format);
   if (pixGetSpp(pix) == 4 && format == IFF_PNG) {
@@ -908,7 +908,7 @@ bool TessPDFRenderer::AddImageHandler(TessBaseAPI* api) {
 
   if (!textonly_) {
     char *pdf_object = nullptr;
-    if (!imageToPDFObj(pix, filename, obj_, &pdf_object, &objsize)) {
+    if (!imageToPDFObj(pix, filename, obj_, &pdf_object, &objsize, jpg_quality_)) {
       return false;
     }
     AppendData(pdf_object, objsize);

api/renderer.h

@@ -187,7 +187,7 @@ class TESS_API TessPDFRenderer : public TessResultRenderer {
  public:
   // datadir is the location of the TESSDATA. We need it because
   // we load a custom PDF font from this location.
-  TessPDFRenderer(const char* outputbase, const char* datadir, bool textonly);
+  TessPDFRenderer(const char* outputbase, const char* datadir, bool textonly, int jpg_quality);
 
  protected:
   virtual bool BeginDocumentHandler();
@@ -205,6 +205,7 @@ class TESS_API TessPDFRenderer : public TessResultRenderer {
   GenericVector<long int> pages_;    // object number for every /Page object
   const char *datadir_;              // where to find the custom font
   bool textonly_;                    // skip images if set
+  int jpg_quality_;                  // set JPEG quality
   // Bookkeeping only. DIY = Do It Yourself.
   void AppendPDFObjectDIY(size_t objectsize);
   // Bookkeeping + emit data.
@@ -213,7 +214,7 @@ class TESS_API TessPDFRenderer : public TessResultRenderer {
   char* GetPDFTextObjects(TessBaseAPI* api, double width, double height);
   // Turn an image into a PDF object. Only transcode if we have to.
   static bool imageToPDFObj(Pix *pix, char *filename, long int objnum,
-                          char **pdf_object, long int *pdf_object_size);
+                          char **pdf_object, long int *pdf_object_size, int jpg_quality);
 };
 
 

api/tesseractmain.cpp

@@ -366,8 +366,10 @@ void PreloadRenderers(
     if (b) {
       bool textonly;
       api->GetBoolVariable("textonly_pdf", &textonly);
+      int jpg_quality;
+      api->GetIntVariable("jpg_quality", &jpg_quality);
       renderers->push_back(new tesseract::TessPDFRenderer(
-          outputbase, api->GetDatapath(), textonly));
+          outputbase, api->GetDatapath(), textonly, jpg_quality));
     }
 
     api->GetBoolVariable("tessedit_write_unlv", &b);

ccmain/tesseractclass.cpp

@@ -394,6 +394,7 @@ Tesseract::Tesseract()
       BOOL_MEMBER(textonly_pdf, false,
                   "Create PDF with only one invisible text layer",
                   this->params()),
+      INT_MEMBER(jpg_quality, 85, "Set JPEG quality level", this->params()),
       STRING_MEMBER(unrecognised_char, "|",
                     "Output char for unidentified blobs", this->params()),
       INT_MEMBER(suspect_level, 99, "Suspect marker level", this->params()),

ccmain/tesseractclass.h

@@ -1032,6 +1032,7 @@ class Tesseract : public Wordrec {
   BOOL_VAR_H(tessedit_create_pdf, false, "Write .pdf output file");
   BOOL_VAR_H(textonly_pdf, false,
              "Create PDF with only one invisible text layer");
+  INT_VAR_H(jpg_quality, 85, "Set JPEG quality level");
   STRING_VAR_H(unrecognised_char, "|",
                "Output char for unidentified blobs");
   INT_VAR_H(suspect_level, 99, "Suspect marker level");