Performs custom processing for PDF operators.
- iOS 2.0+
- macOS 10.4+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
- Core Graphics
A CGPDFScanner object. Core Graphics passes the scanner to your callback function. The scanner contains the PDF content stream that has the PDF operator that corresponds to this callback.
A pointer to data passed to the callback.
Your callback function takes any action that’s appropriate for your application. For example, if you want to count the number of inline images in a PDF but ignore the image data, you would set a callback for the
EI operator. In your callback you would increment a counter for each call.