Compare PDF files on iOS

The Apryse SDK provides powerful file comparison functionality. An example of this capability is shown below by comparing two PDF pages and highlighting the difference between them in red.

File 1	File 2	Difference

The PTDiffViewController class shows a control to select two documents and create a new file showing the visual difference between them with customizable colors.

The file comparison control is part of the Tools library, so make sure you have added the Tools library to your project .

// Initialize a file comparison view controller.
let diffViewController = PTDiffViewController()

// Set the current view controller as the annotation view controller's delegate.
diffViewController.delegate = self

let navigationController = UINavigationController(rootViewController: diffViewController)
if ( UIDevice.current.userInterfaceIdiom == .pad ) {
    navigationController.modalPresentationStyle = .popover
    navigationController.popoverPresentationController?.barButtonItem = documentComparisonButton
}

self.present(navigationController, animated: true, completion: nil)

The following sample code demonstrates how to use PDFNet to generate a document displaying the visual difference between two PDF pages:

func pdfCompareDoc(docA: PTPDFDoc, docB: PTPDFDoc, colorA: PTColorPt, colorB: PTColorPt, blendMode: PTBlendMode) -> PTPDFDoc {
    let pageA = docA.getPage(1)
    let pageB = docB.getPage(1)

    let diffOptions:PTDiffOptions = PTDiffOptions()
    diffOptions.setColorA(colorA)
    diffOptions.setColorB(colorB)
    diffOptions.setBlendMode(blendMode)

    let doc:PTPDFDoc = PTPDFDoc()
    doc.appendVisualDiff(pageA, p2: pageB, opts: diffOptions)
    return doc
}