EXC_BAD_ACCESS error in Xcode

I really need you guy HELP , I run my program in Xcode and its successful but later,

Its show me this error: **Thread 1: Program received signal :"EXC_BAD_ACCESS" on my program line that I have **bold below :

- (NSString *) ocrImage: (UIImage *) uiImage
{
    CGSize imageSize = [uiImage size];
    double bytes_per_line   = CGImageGetBytesPerRow([ui开发者_如何学GoImage CGImage]);
    double bytes_per_pixel  = CGImageGetBitsPerPixel([uiImage CGImage]) / 8.0;

    CFDataRef data = CGDataProviderCopyData(CGImageGetDataProvider([uiImage CGImage]));
    const UInt8 *imageData = CFDataGetBytePtr(data);

    // this could take a while. maybe needs to happen asynchronously.

    **char* text = tess->TesseractRect(imageData,(int)bytes_per_pixel,(int)bytes_per_line, 0, 0,(int) imageSize.height,(int) imageSize.width);**

    // Do something useful with the text!
    NSLog(@"Converted text: %@",[NSString stringWithCString:text encoding:NSUTF8StringEncoding]);

    return [NSString stringWithCString:text encoding:NSUTF8StringEncoding];
}

Thank you guy .

make sure that imageData is not NULL here. That's the most common cause of what you're seeing. You should reconsider your title to something more related to your problem, and focus on the stacktrace and all the variables you are passing to TesseractRect().

The other major likelihood is that tess (whatever that is) is a bad pointer, or that is not part of the correct C++ class (I assume this is Objective-C++; you're not clear on any of that).

- (NSString *)readAndProcessImage:(UIImage *)uiImage
{
  CGSize imageSize = [uiImage size];
  int bytes_per_line = (int)CGImageGetBytesPerRow([uiImage CGImage]);
  int bytes_per_pixel = (int)CGImageGetBitsPerPixel([uiImage CGImage]) / 8.0;

  CFDataRef data =
      CGDataProviderCopyData(CGImageGetDataProvider([uiImage CGImage]));
  const UInt8 *imageData = CFDataGetBytePtr(data);

  // this could take a while. maybe needs to happen asynchronously?
  char *text = tess.TesseractRect(imageData, bytes_per_pixel, bytes_per_line, 0,
                                  0, imageSize.width, imageSize.height);

  NSString *textStr = [NSString stringWithUTF8String:text];

  delete[] text;
  CFRelease(data);
  return textStr;
}