How to use Clarifai crop?

Question

I can recognize image and check for prediction like nsfw,sfw,etc with the following sample code in objective-c.

  // Initialize the Clarifai app with your app's ID and Secret.
ClarifaiApp *app = [[ClarifaiApp alloc] initWithAppID:@""
                                            appSecret:@""];

// Fetch Clarifai's general model.
[app getModelByName:@"general-v1.3" completion:^(ClarifaiModel *model, NSError *error) {
    // Create a Clarifai image from a uiimage.
    ClarifaiImage *clarifaiImage = [[ClarifaiImage alloc] initWithImage:image];

    // Use Clarifai's general model to pedict tags for the given image.
    [model predictOnImages:@[clarifaiImage] completion:^(NSArray<ClarifaiOutput *> *outputs, NSError *error) {
        if (!error) {
            ClarifaiOutput *output = outputs[0];

            // Loop through predicted concepts (tags), and display them on the screen.
            NSMutableArray *tags = [NSMutableArray array];
            for (ClarifaiConcept *concept in output.concepts) {
                [tags addObject:concept.conceptName];
            }
            dispatch_async(dispatch_get_main_queue(), ^{
                self.textView.text = [NSString stringWithFormat:@"Tags:\n%@", [tags componentsJoinedByString:@", "]];
            });
        }

      dispatch_async(dispatch_get_main_queue(), ^{
        self.button.enabled = YES;
      });

    }];
}];

For this I can get model and from that model i can predict images.

Question:

How can I make the crop function? I am not getting a way to reach the crop functionality available in Clarifai .

Any ideas.

Answer 1

You can create a crop using the ClarifaiCrop class and using it to initialize a ClarifaiImage.

ClarifaiCrop *crop = [[ClarifaiCrop alloc] initWithTop:0.1 
                                                  left:0.1
                                                bottom:0.1
                                                 right:0.1];

Where top, left, bottom, and right are percentages (between 0 and 1) of the distances from the borders of the image to the region of interest. In the example above the image would be cropped 10% from each margin.

ClarifaiImage *clarifaiImage = [[ClarifaiImage alloc] initWithImage:image 
                                                            andCrop:crop];