get bitmap from image

gistfile1.m

unsigned char *getBitmapFromImage(UIImage *image)
{
  CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
  
  if (colorSpace == NULL) {
    fprintf(stderr, "Error allocating color space\n");
    return NULL;
  }

  CGSize size = image.size;
  void *bitmapData = malloc(size.width * size.height * 4);
  
  if (bitmapData == NULL) {
    fprintf(stderr, "Error: Memory not allocated");
    return NULL;
  }

  CGContextRef = context = CGBitmapContextCreate(bitmapData, size.width, size.height, 8, size.width * 4, colorSpace, kCGImageAlphaPremultipliedFirst);
  
  if (context == NULL) {
    fprintf(stderr, "Error: Context not created");
    free(bitmapData);
    return NULL;
  }

  CGRect rect = CGRectMake(0.0f, 0.0f, size.width, size.height);
  CGContextDrawImage(context, rect, image.CGImage);
  unsigned char *data = CGBitmapContextGetData(context);
  CGContextRelease(context);
  return data;
}