1 files changed, 130 insertions, 0 deletions
diff --git a/helium/heliumtextdetector.cpp b/helium/heliumtextdetector.cpp
new file mode 100644
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--- /dev/null
+++ b/helium/heliumtextdetector.cpp
@@ -0,0 +1,130 @@
+// Copyright 2006 Google Inc.
+// All Rights Reserved.
+// Author: <renn@google.com> (Marius Renn)
+//
+// Local includes
+#include <time.h>
+#include "clusterer.h"
+#include "contourdetector.h"
+#include "debugging.h"
+#include "edgedetector.h"
+#include "gaussiansmooth.h"
+#include "heliumtextdetector.h"
+#include "maxtracer.h"
+#include "imageenhancer.h"
+#include "image.h"
+#include "quicksmooth.h"
+#include "shapetree.h"
+#include "sobeledgedetector.h"
+#include "laplaceedgedetector.h"
+#include "textclassifier.h"
+#include "textvalidator.h"
+#include "leptonica.h"
+
+using namespace helium;
+
+
+static void ShowTrace(ContourDetector& outliner, int trace_type,
+                      int width, int height) {
+  Mask mask(width, height);
+  outliner.PlotTracesOnto(mask, trace_type);
+  Image trace_image = Image::FromMask(mask);
+  Leptonica::DisplayImage(trace_image);
+}
+
+static void ShowShapeTree(Clusterer& clusterer, ShapeTree& shapes,
+                          int width, int height) {
+  Image image(width, height);
+  image.Clear();
+  shapes.PaintShapes(image);
+  clusterer.DrawClusterBounds(image);
+  Leptonica::DisplayImage(image);
+}
+
+HeliumTextDetector::HeliumTextDetector()
+  : parameters_(),
+    clusterer_(),
+    shapemaker_(),
+    text_areas_(NULL),
+    show_debug_(false) {
+}
+
+HeliumTextDetector::~HeliumTextDetector() {
+  delete text_areas_;
+  delete parameters_.edge_detector;
+  delete parameters_.tracer;
+}
+
+void HeliumTextDetector::SetDefaultParameters() {
+  parameters_.use_gaussian_smoothing = false;
+  parameters_.gaussian_strength = 3;
+  parameters_.edge_detector = new SobelEdgeDetector();
+  // parameters_.edge_detector = new LaplaceEdgeDetector();
+  parameters_.tracer = new MaxTracer(24);
+  parameters_.trace_threshold = 16;
+}
+
+const TextAreas& HeliumTextDetector::GetTextAreas() {
+  GetMutableTextAreas();
+  return *text_areas_;
+}
+
+TextAreas* HeliumTextDetector::GetMutableTextAreas() {
+  if (!text_areas_) {
+    text_areas_ = new TextAreas(clusterer_.clusters());
+  }
+  return text_areas_;
+}
+
+void HeliumTextDetector::DetectText(const Image& image) {
+  ASSERT(image.Valid());
+
+  // Clean up any remains from last detection
+  delete(text_areas_);
+  text_areas_ = NULL;
+
+  // Parameters set?
+  ASSERT(parameters_.edge_detector && parameters_.tracer);
+
+  // Smooth image
+  Image smooth_image;
+  if (parameters_.use_gaussian_smoothing) {
+    GaussianSmooth gaussian_blur(parameters_.gaussian_strength);
+    smooth_image = gaussian_blur.Smooth(image);
+  } else {
+    smooth_image.Copy(image);
+    QuickSmooth::Smooth(smooth_image);
+  }
+
+  ImageEnhancer::EnhanceColors(smooth_image, kMinDynamicRange);
+
+  // Edge detection
+  EdgeDetector* detector = parameters_.edge_detector;
+  GrayMap edges = detector->DetectEdges(smooth_image);
+  ImageEnhancer::LocalContrast(edges);
+
+  // Tracing
+  TextClassifier text_classifier;
+  Tracer* tracer = parameters_.tracer;
+  tracer->set_trace_map(&edges);
+  ContourDetector outliner(*tracer, text_classifier);
+  outliner.DetectContours(edges,
+                          parameters_.trace_threshold,
+                          smooth_image);
+
+  // Labeling
+  shapemaker_.ClearShapes();
+  shapemaker_.ConvertTraces(outliner.contours(), smooth_image);
+
+  // Clustering
+  TextValidator text_validator;
+  clusterer_.ClearClusters();
+  clusterer_.ClusterShapes(shapemaker_.shapes(), text_validator);
+
+  if (show_debug_) {
+    Leptonica::DisplayImage(smooth_image);
+    Leptonica::DisplayGrayMap(edges);
+    ShowTrace(outliner, TRACECLASS_TEXT, image.width(), image.height());
+    ShowShapeTree(clusterer_, shapemaker_, image.width(), image.height());
+  }
+}