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Wrap up

This has been the briefest possible introduction to Core Image, yet we still managed to make something useful, using UISlider for the first time and even writing images to the photo album.

Unless you really do intend to make Yet Another Core Image Filters Program (best of luck!) your use of Core Image will mostly be about manipulating a picture in a very specific way, using a filter you have hand-crafted to look great.

If you want to try other filters, search on Google for "Core Image Filter Reference" and have a read – it will list the input keys for each of them so that you can get really fine-grained control over the filters.

Review what you learned

Anyone can sit through a tutorial, but it takes actual work to remember what was taught. It’s my job to make sure you take as much from these tutorials as possible, so I’ve prepared a short review to help you check your learning.

Click here to review what you learned in project 13.

Challenge

One of the best ways to learn is to write your own code as often as possible, so here are three ways you should try your new knowledge to make sure you fully understand what’s going on:

Try making the Save button show an error if there was no image in the image view.
Make the Change Filter button change its title to show the name of the currently selected filter.
Experiment with having more than one slider, to control each of the input keys you care about. For example, you might have one for radius and one for intensity.

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Share your success!

One of the most effective motivators of success is sharing your progress with other people – when you tell folks what you're doing and what you've learned, it encourages you to come back for more, which in turn will help you reach your app development goals faster.

So, now that you've done all the hard work it's time to share your success: tell folks that you've completed this project, either by clicking the button below to start composing a tweet, or by writing your own message from scratch. This will definitely encourage you to keep learning, but it will also help other folks discover my work – thank you!