Show page box info of PDF by using Swift and Quartz ( http://doratex.hatenablog.jp/entry/20150909/1441748482 )

pageboxinfo.swift

// How to compile:
//   swiftc -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk -o pageboxinfo pageboxinfo.swift
import Foundation
import Quartz

extension CGPDFBox {
    var title: String {
        switch self {
        case .mediaBox:
            return "MediaBox: "
        case .cropBox:
            return "CropBox:  "
        case .bleedBox:
            return "BleedBox: "
        case .trimBox:
            return "TrimBox:  "
        case .artBox:
            return "ArtBox:   "
        }
    }
}

struct PageBox {
    private let pdfPage: PDFPage
    
    init(pdfPage: PDFPage) {
        self.pdfPage = pdfPage
    }
    
    private func bboxString(boxType: CGPDFBox, clipWithMediaBox: Bool, hires: Bool = true) -> String {
        let pageRef = pdfPage.pageRef!
        let mediaBoxRect = pageRef.getBoxRect(.mediaBox)
        var rect = pageRef.getBoxRect(boxType)
        rect = clipWithMediaBox ? rect.intersection(mediaBoxRect) : rect

        if hires {
            return String(format:"%8.2f %8.2f %8.2f %8.2f",
                rect.origin.x,
                rect.origin.y,
                rect.origin.x + rect.size.width,
                rect.origin.y + rect.size.height)
        } else {
            return String(format:"%d %d %d %d",
                floor(rect.origin.x),
                floor(rect.origin.y),
                floor(rect.origin.x) + ceil(rect.size.width),
                floor(rect.origin.y) + ceil(rect.size.height))
        }
    }
    
    private func printBox(_ boxType: CGPDFBox, prefix: String = "", hires: Bool = true) {
        let rawBox = bboxString(boxType: boxType, clipWithMediaBox: false, hires: hires)
        let clippedBox = bboxString(boxType: boxType, clipWithMediaBox: true, hires: hires)
        let title = boxType.title
        
        print(prefix + title + rawBox)
        
        if rawBox != clippedBox {
            print(" *clipped " + title + clippedBox)
        }
    }
    
    func printAllBoxes(prefix: String = "") {
        printBox(.mediaBox, prefix: prefix)
        printBox(.cropBox,  prefix: prefix)
        printBox(.bleedBox, prefix: prefix)
        printBox(.trimBox,  prefix: prefix)
        printBox(.artBox,   prefix: prefix)
        print(prefix + "Rotation: \(pdfPage.rotation)")
    }
}

func printPageBoxes(filePath: String) {
    let url = URL(fileURLWithPath: filePath)
    guard let doc = PDFDocument(url: url) else {
        print("ERROR: Invalid file - \(filePath)")
        return
    }
    
    let pageCount = doc.pageCount
    let printBar = { print("---------------------------------------------------------") }
    
    printBar()
    (0..<pageCount).forEach { pageIndex in
        let pageBox = PageBox(pdfPage: doc.page(at: pageIndex)!)
        pageBox.printAllBoxes(prefix: String(format: "Page %4d ", pageIndex+1))
        printBar()
    }
}

// Main

let arguments = ProcessInfo.processInfo.arguments

guard arguments.count == 2 else {
    print("Usage: \((arguments[0] as NSString).lastPathComponent) <PDF_FILE_NAME>")
    exit(1)
}

let pdfPath = arguments[1]

guard FileManager.default.fileExists(atPath: pdfPath) else {
    print("ERROR: \(pdfPath) does not exist.")
    exit(1)
}

printPageBoxes(filePath: pdfPath)