Importing an Image with Core Image - Core Image from CIImage to Metal & Beyond

Create a CIImage from a file, discover how to handle rotation and see how to import a depth map in a portrait photo. About the Course: Core Image is an oft-overlooked first-party framework on Apple platforms for the efficient processing of images and videos. It includes a wide range of built-in filters, as well as the ability to build your own custom filters using Metal. Discover how to integrate Core Image into your own apps, and how the optimized image processing can save your users time and battery life. Learn how to perform real-time video processing, and how you can extend Core Image by implementing your own custom filters directly in Metal. View the Complete Course Here: https://www.raywenderlich.com/5428948... --- About www.raywenderlich.com: raywenderlich.com is a website focused on developing high-quality programming tutorials. Our goal is to take the coolest and most challenging topics and make them easy for everyone to learn – so we can all make amazing apps. We are also focused on developing a strong community. Our goal is to help each other reach our dreams through friendship and cooperation. As you can see below, a bunch of us have joined forces to make this happen: authors, editors, subject matter experts, app reviewers, and most importantly our amazing readers! ---- Core Image is an image processing and analysis technology designed to provide near real-time processing for still and video images. It operates on image data types from the Core Graphics, Core Video, and Image I/O frameworks, using either a GPU or CPU rendering path. Core Image hides the details of low-level graphics processing by providing an easy-to-use application programming interface (API). You don’t need to know the details of OpenGL, OpenGL ES, or Metal to leverage the power of the GPU, nor do you need to know anything about Grand Central Dispatch (GCD) to get the benefit of multicore processing. Core Image handles the details for you. Core Image is Efficient and Easy to Use for Processing and Analyzing Images Core Image provides hundreds of built-in filters. You set up filters by supplying key-value pairs for a filter’s input parameters. The output of one filter can be the input of another, making it possible to chain numerous filters together to create amazing effects. If you create a compound effect that you want to use again, you can subclass CIFilter to capture the effect “recipe.” There are more than a dozen categories of filters. Some are designed to achieve artistic results, such as the stylize and halftone filter categories. Others are optimal for fixing image problems, such as color adjustment and sharpen filters. Core Image can analyze the quality of an image and provide a set of filters with optimal settings for adjusting such things as hue, contrast, and tone color, and for correcting for flash artifacts such as red eye. It does all this with one method call on your part. Core Image can detect human face features in still images and track them over time in video images. Knowing where faces are can help you determine where to place a vignette or apply other special filters. Query Core Image to Get a List of Filters and Their Attributes Core Image has “built-in” reference documentation for its filters. You can query the system to find out which filters are available. Then, for each filter, you can retrieve a dictionary that contains its attributes, such as its input parameters, defaults parameter values, minimum and maximum values, display name, and more. Core Image Can Achieve Real-Time Video Performance If your app needs to process video in real-time, there are several things you can do to optimize performance.Use an Image Accumulator to Support Feedback-Based Processing The CIImageAccumulator class is designed for efficient feedback-based image processing, which you might find useful if your app needs to image dynamical systems. Create and Distribute Custom Kernels and Filters If none of the built-in filters suits your needs, even when chained together, consider creating a custom filter. You’ll need to understand kernels—programs that operate at the pixel level—because they are at the heart of every filter. In macOS, you can package one or more custom filter as an image unit so that other apps can load and use them. Processing Images Processing images means applying filters—an image filter is a piece of software that examines an input image pixel by pixel and algorithmically applies some effect in order to create an output image. In Core Image, image processing relies on the CIFilter and CIImage classes, which describe filters and their input and output. To apply filters and display or export results, you can make use of the integration between Core Image and other system frameworks, or create your own rendering workflow with the CIContext class.