property |NSURL| : a reference to current application’s |NSURL|
property NSArray : a reference to current application’s NSArray
property NSPredicate : a reference to current application’s NSPredicate
property NSCountedSet : a reference to current application’s NSCountedSet
property NSURLTypeIdentifierKey : a reference to current application’s NSURLTypeIdentifierKey

script spd
　　property fList : {}
　　property fRes : {}
　　property md5List : {}
　　property fmdList : {}
　　property dupRes : {}
　　property outList : {}
end script

set anUTI to "public.image"

set aFol to choose folder
–set aFol to path to pictures folder

set (fList of spd) to getFilePathList(aFol) of me

–指定のFile listのうち画像のみ抽出
set (fRes of spd) to filterAliasListByUTI((fList of spd), "public.image") of me
if (fRes of spd) = {} then return

–すべての画像のMD5チェックサムを計算
set (md5List of spd) to {}
set (fmdList of spd) to {}

repeat with i in (fRes of spd)
　　set j to contents of i
　　set md5Res to (current application’s FileHash’s md5HashOfFileAtPath:(j)) as string
　　set the end of (md5List of spd) to md5Res
　　set the end of (fmdList of spd) to {filePath:j, md5:md5Res}
end repeat

–チェックサムが重複している画像を取り出す
set fmdArray to NSArray’s arrayWithArray:(fmdList of spd)

set (dupRes of spd) to returnDuplicatesOnly((md5List of spd)) of me
set (outList of spd) to {}
set procMDs to {}

repeat with i in (dupRes of spd)
　　set j to contents of i
　　
　　if j is not in procMDs then
　　　　set aRes to filterDictArrayByLabel(fmdArray, "md5 == ’" & j & "’") of me
　　　　
　　　　set tmpMD5 to filePath of (first item of aRes)
　　　　
　　　　set tmpRes to {}
　　　　repeat with ii in aRes
　　　　　　set jj to contents of ii
　　　　　　set the end of tmpRes to filePath of jj
　　　　end repeat
　　　　
　　　　set aRec to {md5:j, fileRes:tmpRes}
　　　　set the end of (outList of spd) to aRec
　　　　set the end of procMDs to j
　　end if
end repeat

return (outList of spd)

–リストに入れたレコードを、指定の属性ラベルの値で抽出
on filterDictArrayByLabel(aArray, aPredicate as string)
　　–抽出
　　set aPredicate to current application’s NSPredicate’s predicateWithFormat:aPredicate
　　set filteredArray to aArray’s filteredArrayUsingPredicate:aPredicate
　　
　　–NSArrayからListに型変換して返す
　　set bList to filteredArray as list
　　return bList
end filterDictArrayByLabel

on getFilePathList(aFol)
　　set aURL to current application’s |NSURL|’s fileURLWithPath:(POSIX path of aFol)
　　set aFM to current application’s NSFileManager’s defaultManager()
　　set urlArray to aFM’s contentsOfDirectoryAtURL:aURL includingPropertiesForKeys:{} options:(current application’s NSDirectoryEnumerationSkipsHiddenFiles) |error|:(missing value)
　　return urlArray as anything
end getFilePathList

–Alias listから指定UTIに含まれるものをPOSIX pathのリストで返す
on filterAliasListByUTI(aList, targUTI)
　　set newList to {}
　　repeat with i in aList
　　　　set j to POSIX path of i
　　　　set tmpUTI to my retUTIfromPath(j)
　　　　set utiRes to my filterUTIList({tmpUTI}, targUTI)
　　　　if utiRes is not equal to {} then
　　　　　　set the end of newList to j
　　　　end if
　　end repeat
　　return newList
end filterAliasListByUTI

–指定のPOSIX pathのファイルのUTIを求める
on retUTIfromPath(aPOSIXPath)
　　set aURL to |NSURL|’s fileURLWithPath:aPOSIXPath
　　set {theResult, theValue} to aURL’s getResourceValue:(reference) forKey:NSURLTypeIdentifierKey |error|:(missing value)
　　
　　if theResult = true then
　　　　return theValue as string
　　else
　　　　return theResult
　　end if
end retUTIfromPath

–UTIリストが指定UTIに含まれているかどうか演算を行う
on filterUTIList(aUTIList, aUTIstr)
　　set anArray to NSArray’s arrayWithArray:aUTIList
　　set aPred to NSPredicate’s predicateWithFormat_("SELF UTI-CONFORMS-TO %@", aUTIstr)
　　set bRes to (anArray’s filteredArrayUsingPredicate:aPred) as list
　　return bRes
end filterUTIList

on returnDuplicatesOnly(aList as list)
　　set aSet to NSCountedSet’s alloc()’s initWithArray:aList
　　set bList to (aSet’s allObjects()) as list
　　
　　set dupList to {}
　　repeat with i in bList
　　　　set aRes to (aSet’s countForObject:i)
　　　　if aRes > 1 then
　　　　　　set the end of dupList to (contents of i)
　　　　end if
　　end repeat
　　
　　return dupList
end returnDuplicatesOnly