#import <TesseractOCR/TesseractOCR.h>
@interface MyViewController : UIViewController <G8TesseractDelegate>
@end

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Languages are used for recognition (e.g. eng, ita, etc.). Tesseract engine
    // will search for the .traineddata language file in the tessdata directory. 
    // For example, specifying "eng+ita" will search for "eng.traineddata" and
    // "ita.traineddata". Cube engine will search for "eng.cube.*" files.
    // See https://github.com/tesseract-ocr/tessdata.
    // Create your G8Tesseract object using the initWithLanguage method:
    G8Tesseract *tesseract = [[G8Tesseract alloc] initWithLanguage:@"eng+ita"];
    // Optionaly: You could specify engine to recognize with. 
    // G8OCREngineModeTesseractOnly by default. It provides more features and faster
    // than Cube engine. See G8Constants.h for more information.
    //tesseract.engineMode = G8OCREngineModeTesseractOnly;
    // Set up the delegate to receive Tesseract's callbacks.
    // self should respond to TesseractDelegate and implement a
    // "- (BOOL)shouldCancelImageRecognitionForTesseract:(G8Tesseract *)tesseract"
    // method to receive a callback to decide whether or not to interrupt
    // Tesseract before it finishes a recognition.
    tesseract.delegate = self;
    // Optional: Limit the character set Tesseract should try to recognize from
    tesseract.charWhitelist = @"0123456789";
    // This is wrapper for common Tesseract variable kG8ParamTesseditCharWhitelist:
    // [tesseract setVariableValue:@"0123456789" forKey:kG8ParamTesseditCharBlacklist];
    // See G8TesseractParameters.h for a complete list of Tesseract variables
    // Optional: Limit the character set Tesseract should not try to recognize from
    //tesseract.charBlacklist = @"OoZzBbSs";
    // Specify the image Tesseract should recognize on
    tesseract.image = [[UIImage imageNamed:@"image_sample.jpg"] g8_blackAndWhite];
    // Optional: Limit the area of the image Tesseract should recognize on to a rectangle
    tesseract.rect = CGRectMake(20, 20, 100, 100);
    // Optional: Limit recognition time with a few seconds
    tesseract.maximumRecognitionTime = 2.0;
    // Start the recognition
    [tesseract recognize];
    // Retrieve the recognized text
    NSLog(@"%@", [tesseract recognizedText]);
    // You could retrieve more information about recognized text with that methods:
    NSArray *characterBoxes = [tesseract recognizedBlocksByIteratorLevel:G8PageIteratorLevelSymbol];
    NSArray *paragraphs = [tesseract recognizedBlocksByIteratorLevel:G8PageIteratorLevelParagraph];
    NSArray *characterChoices = tesseract.characterChoices;
    UIImage *imageWithBlocks = [tesseract imageWithBlocks:characterBoxes drawText:YES thresholded:NO]; 
}
- (void)progressImageRecognitionForTesseract:(G8Tesseract *)tesseract {
    NSLog(@"progress: %lu", (unsigned long)tesseract.progress);
}
- (BOOL)shouldCancelImageRecognitionForTesseract:(G8Tesseract *)tesseract {
    return NO;  // return YES, if you need to interrupt tesseract before it finishes
}

#import <TesseractOCR/TesseractOCR.h>
@interface MyViewController : UIViewController
@end

- (void)viewDidLoad
{
    // Create RecognitionOperation
    G8RecognitionOperation *operation = [[G8RecognitionOperation alloc] initWithLanguage:@"eng+ita"];
    // Configure inner G8Tesseract object as described before
    operation.tesseract.charWhitelist = @"01234567890";
    operation.tesseract.image = [[UIImage imageNamed:@"image_sample.jpg"] g8_blackAndWhite];
    // Setup the recognitionCompleteBlock to receive the Tesseract object
    // after text recognition. It will hold the recognized text.
    operation.recognitionCompleteBlock = ^(G8Tesseract *recognizedTesseract) {
        // Retrieve the recognized text upon completion
        NSLog(@"%@", [recognizedTesseract recognizedText]);
    };
    // Add operation to queue
    NSOperationQueue *queue = [[NSOperationQueue alloc] init];
    [queue addOperation:operation];
}