property |NSURL| : a reference to current application’s |NSURL|
property NSString : a reference to current application’s NSString
property NSImage : a reference to current application’s NSImage
property NSScreen : a reference to current application’s NSScreen
property NSNumber : a reference to current application’s NSNumber
property NSZeroPoint : a reference to current application’s NSZeroPoint
property PDFDocument : a reference to current application’s PDFDocument
property NSJPEGFileType : a reference to current application’s NSJPEGFileType
property NSCompositeCopy : a reference to current application’s NSCompositeCopy
property NSGraphicsContext : a reference to current application’s NSGraphicsContext
property NSBitmapImageRep : a reference to current application’s NSBitmapImageRep
property NSNumberFormatter : a reference to current application’s NSNumberFormatter
property NSImageInterpolationHigh : a reference to current application’s NSImageInterpolationHigh

tell application "Skim"
　　set docCount to count every document
　　if docCount = 0 then return
　　
　　tell front document
　　　　set curInd to index of current page
　　　　set docFile to file of it
　　end tell
end tell

set aPOSIX to POSIX path of docFile
set aURL to (|NSURL|’s fileURLWithPath:aPOSIX)

set aPDFdoc to PDFDocument’s alloc()’s initWithURL:aURL
set pCount to aPDFdoc’s pageCount()

set compFactor to 1.0 –1.0 — 0.0 = max jpeg compression, 1.0 = none

–Detect Retina Environment
set retinaF to NSScreen’s mainScreen()’s backingScaleFactor()
if retinaF = 1.0 then
　　set aScale to 2.0 –Non Retina Env
else
　　set aScale to 1.0 –Retina Env
end if

–PDFをページごとに分割してJPEGでファイル書き出し
set i to (curInd – 1) –AppleScript index (1 based) to Cocoa index (0 based) conversion

–Pick Up a PDF page as an image
set thisPage to (aPDFdoc’s pageAtIndex:(i))
set thisDoc to (NSImage’s alloc()’s initWithData:(thisPage’s dataRepresentation()))
if thisDoc = missing value then error "Error in getting imagerep from PDF in page:" & (i as string)

–Resize Image
set pointSize to thisDoc’s |size|()
set newSize to current application’s NSMakeSize((pointSize’s width) * aScale, (pointSize’s height) * aScale)
set newImage to (NSImage’s alloc()’s initWithSize:newSize)

newImage’s lockFocus()
(thisDoc’s setSize:newSize)
(NSGraphicsContext’s currentContext()’s setImageInterpolation:(NSImageInterpolationHigh))
(thisDoc’s drawAtPoint:(NSZeroPoint) fromRect:(current application’s CGRectMake(0, 0, newSize’s width, newSize’s height)) operation:(NSCompositeCopy) fraction:2.0)
newImage’s unlockFocus()

–Save Image as JPEG
set theData to newImage’s TIFFRepresentation()
set newRep to (NSBitmapImageRep’s imageRepWithData:theData)
set targData to (newRep’s representationUsingType:(NSJPEGFileType) |properties|:{NSImageCompressionFactor:compFactor, NSImageProgressive:false})
set zText to retZeroPaddingText((i + 1), 4) of me
set outPath to addString_beforeExtensionIn_addingExtension_("_" & zText, aPOSIX, "jpg")

(targData’s writeToFile:outPath atomically:true) –書き出し

–ファイルパス（POSIX path）に対して、文字列（枝番）を追加。任意の拡張子を追加
on addString:extraString beforeExtensionIn:aPath addingExtension:aExt
　　set pathString to NSString’s stringWithString:aPath
　　set theExtension to pathString’s pathExtension()
　　set thePathNoExt to pathString’s stringByDeletingPathExtension()
　　
　　set newPath to (thePathNoExt’s stringByAppendingString:extraString)’s stringByAppendingPathExtension:aExt
　　return newPath as string
end addString:beforeExtensionIn:addingExtension:

on retZeroPaddingText(aNum as integer, aDigitNum as integer)
　　if aNum > (((10 ^ aDigitNum) as integer) – 1) then return "" –Range Check
　　set aFormatter to NSNumberFormatter’s alloc()’s init()
　　aFormatter’s setUsesGroupingSeparator:false
　　aFormatter’s setAllowsFloats:false
　　aFormatter’s setMaximumIntegerDigits:aDigitNum
　　aFormatter’s setMinimumIntegerDigits:aDigitNum
　　aFormatter’s setPaddingCharacter:"0"
　　set aStr to aFormatter’s stringFromNumber:(NSNumber’s numberWithFloat:aNum)
　　return aStr as string
end retZeroPaddingText