use AppleScript version "2.4"
use scripting additions
use framework "Foundation"
use framework "Quartz"
use framework "QuartzCore"
use framework "AppKit"

set aHFSPath to (choose file of type {"com.adobe.pdf"} with prompt "ページごとに分解するPDFを指定してください")
set aPOSIX to POSIX path of aHFSPath
set aURL to (current application’s |NSURL|’s fileURLWithPath:aPOSIX)

set aPOSIXpath to POSIX path of aHFSPath —書き出し先パスをPOSIX pathで用意しておく（あとで加工）

set aPDFdoc to current application’s 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 current application’s 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
repeat with i from 0 to (pCount – 1)
　　–Pick Up a PDF page as an image
　　set thisPage to (aPDFdoc’s pageAtIndex:(i))
　　set thisDoc to (current application’s 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 (current application’s NSImage’s alloc()’s initWithSize:newSize)
　　
　　newImage’s lockFocus()
　　(thisDoc’s setSize:newSize)
　　(current application’s NSGraphicsContext’s currentContext()’s setImageInterpolation:(current application’s NSImageInterpolationHigh))
　　(thisDoc’s drawAtPoint:(current application’s NSZeroPoint) fromRect:(current application’s CGRectMake(0, 0, newSize’s width, newSize’s height)) operation:(current application’s NSCompositeCopy) fraction:1.0)
　　newImage’s unlockFocus()
　　
　　–Save Image as JPEG
　　set theData to newImage’s TIFFRepresentation()
　　set newRep to (current application’s NSBitmapImageRep’s imageRepWithData:theData)
　　set targData to (newRep’s representationUsingType:(current application’s NSJPEGFileType) |properties|:{NSImageCompressionFactor:compFactor, NSImageProgressive:false})
　　set zText to retZeroPaddingText((i + 1), 4) of me
　　set outPath to addString_beforeExtensionIn_addingExtension_("_" & zText, aPOSIXpath, "jpg")
　　
　　(targData’s writeToFile:outPath atomically:true) –書き出し
end repeat

–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 current application’s 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: