Refactored OCR reading class into several internal methods.

Author: klanderfri

ReadMagicCard/CardReader.cpp

@@ -157,10 +157,11 @@ bool CardReader::hasResultFailed(OcrDecodeResult result) {
 OcrDecodeResult CardReader::ocrReadTitle(vector<Mat> ocrTitles) {
 
 	OcrDecodeResult bestResult;
+	ImageOcrHelper ocrReader(systemMethods);
 
 	for (Mat ocrTitle : ocrTitles) {
 
-		OcrDecodeResult result = ImageOcrHelper::DecodeTitle(ocrTitle, systemMethods);
+		OcrDecodeResult result = ocrReader.DecodeImage(ocrTitle);
 
 		if (bestResult.Confidence < result.Confidence) {
 			bestResult = result;

ReadMagicCard/ImageOcrHelper.cpp

@@ -5,33 +5,57 @@ using namespace std;
 using namespace cv;
 using namespace tesseract;
 
-ImageOcrHelper::ImageOcrHelper()
+ImageOcrHelper::ImageOcrHelper(SystemMethods* systemMethods)
 {
+	this->systemMethods = systemMethods;
+
+	//Setup the OCR API.
+	pathToTrainedData = getTrainedDataPath();
+	setupTessBaseAPI(pathToTrainedData);
 }
 
 ImageOcrHelper::~ImageOcrHelper()
 {
 }
 
-OcrDecodeResult ImageOcrHelper::DecodeTitle(Mat originalImageData, SystemMethods* systemMethods) {
+OcrDecodeResult ImageOcrHelper::DecodeImage(Mat originalImageData) {
+
+	//Set the current image to read.
+	setImage(originalImageData);
+
+	//Read the image.
+	OcrDecodeResult result;
+	result.Text = getUTF8Text(systemMethods);
+	result.Confidence = ocr.MeanTextConf();
+
+	return result;
+}
+
+string ImageOcrHelper::getTrainedDataPath() {
+
+	return systemMethods->ToString(systemMethods->GetPathToExeParentDirectory()) + "tessdata";
+}
 
-	string trainedDataFolderPath = systemMethods->ToString(systemMethods->GetPathToExeParentDirectory()) + "tessdata";
-	const char* path = trainedDataFolderPath.c_str();
-	tesseract::TessBaseAPI ocr;
-	ocr.Init(path, "eng", OEM_TESSERACT_ONLY);
+void ImageOcrHelper::setupTessBaseAPI(string trainedDataPath) {
+
+	ocr.Init(trainedDataPath.c_str(), "eng", OEM_TESSERACT_ONLY);
 	ocr.SetPageSegMode(PSM_SINGLE_LINE);
+}
+
+void ImageOcrHelper::setImage(Mat originalImageData) {
+
 	ocr.SetImage((uchar*)originalImageData.data, originalImageData.cols, originalImageData.rows, originalImageData.channels(), originalImageData.step1());
+}
 
-	OcrDecodeResult result;
+wstring ImageOcrHelper::getUTF8Text(SystemMethods* systemMethods) {
 
 	char* rawOutText = ocr.GetUTF8Text();
 	wstring outText = systemMethods->ToWString(string(rawOutText));
-	delete[] rawOutText; //As instructed by documentation in the GetUTF8Text method.
+	outText = removeTrailingNewline(outText);
 
-	result.Text = removeTrailingNewline(outText);
-	result.Confidence = ocr.MeanTextConf();
+	delete[] rawOutText; //As instructed by documentation in the GetUTF8Text method.
 
-	return result;
+	return outText;
 }
 
 wstring ImageOcrHelper::removeTrailingNewline(wstring title) {

ReadMagicCard/ImageOcrHelper.h

@@ -6,14 +6,28 @@
 class ImageOcrHelper
 {
 public:
-	ImageOcrHelper();
+	ImageOcrHelper(SystemMethods* systemMethods);
 	~ImageOcrHelper();
 
-	//Decodes the title image and turns it into a wstring. The result also contains the Tesseract confidence.
-	static OcrDecodeResult DecodeTitle(cv::Mat originalImageData, SystemMethods* systemMethods);
+	//Decodes the image and turns it into a wstring. The result also contains the OCR API confidence.
+	OcrDecodeResult DecodeImage(cv::Mat originalImageData);
 
 private:
-
+	//Gets the path to the folder containing the trained language data files.
+	std::string getTrainedDataPath();
+	//Sets up the OCR API so it can be used for reading images.
+	void setupTessBaseAPI(std::string trainedDataPath);
+	//Sets the current image to read.
+	void setImage(cv::Mat originalImageData);
+	//Gets the text in the image (formated as UTF8).
+	std::wstring getUTF8Text(SystemMethods* systemMethods);
 	//Removes the newlines from the end of the title.
-	static std::wstring removeTrailingNewline(std::wstring title);
+	std::wstring removeTrailingNewline(std::wstring title);
+
+	//The OCR API used for reading images.
+	tesseract::TessBaseAPI ocr;
+	//The path to the folder containing the trained language data files.
+	std::string pathToTrainedData;
+	//Pointer to object handling the system dependent methods.
+	SystemMethods* systemMethods;
 };