use AppleScript version "2.8" — macOS 12 or later
use framework "Foundation"
use framework "AppKit"
use scripting additions

property NSData : a reference to current application’s NSData
property |NSURL| : a reference to current application’s |NSURL|
property NSColor : a reference to current application’s NSColor
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 NSBezierPath : a reference to current application’s NSBezierPath
property NSPNGFileType : a reference to current application’s NSPNGFileType
property NSMutableArray : a reference to current application’s NSMutableArray
property NSBitmapImageRep : a reference to current application’s NSBitmapImageRep

–画像分割ブロックサイズ
property imgDivXStep : 16
property imgDivYStep : 16

script spd
　　property outList : {}
end script

set aFile to POSIX path of (choose file with prompt "PNG画像を選択")

–時間計測用
set a1Dat to current application’s NSDate’s timeIntervalSinceReferenceDate()

set aURL to |NSURL|’s fileURLWithPath:aFile
set aImage to NSImage’s alloc()’s initWithContentsOfURL:aURL

set sRes to aImage’s |size|()
–> example: {width:196.0, height:309.0}

set aHeight to height of sRes
set aWidth to width of sRes

set xBlockSize to (aWidth div imgDivXStep)
set yBlockSize to (aHeight div imgDivYStep)

–transparent block sample
set blankImg to makeNSImageWithFilledWithColor(xBlockSize, yBlockSize, current application’s NSColor’s clearColor()) of me
set blankBit to blankImg’s TIFFRepresentation()

set (outList of spd) to {}

repeat with y from 0 to (aHeight – yBlockSize) by yBlockSize
　　set oneLine to ""
　　
　　repeat with x from 0 to (aWidth – xBlockSize) by xBlockSize
　　　　–crop a part of image and check transparent
　　　　set tmpImg to (my cropNSImageBy:{x, y, xBlockSize, yBlockSize} fromImage:aImage)
　　　　set tmpBit to tmpImg’s TIFFRepresentation()
　　　　set chkTrans to (blankBit’s isEqualToData:tmpBit) as boolean
　　　　
　　　　if chkTrans = false then –Not transparent block
　　　　　　set the end of (outList of spd) to {xPos:x, yPos:y}
　　　　end if
　　end repeat
　　
end repeat

–時間計測用
set b1Dat to current application’s NSDate’s timeIntervalSinceReferenceDate()
set c1Dat to b1Dat – a1Dat
log c1Dat

–最大値、最小値を取得
set nArray to (NSMutableArray’s arrayWithArray:(outList of spd))

set xMin to calcMin("xPos", nArray) of me
set xMax to calcMax("xPos", nArray) of me

set yMin to calcMin("yPos", nArray) of me
set yMax to calcMax("yPos", nArray) of me

–オリジナル画像を切り抜き
set cImage to my cropNSImageTo:{xMin + (xBlockSize / 2), yMin + (yBlockSize / 2), xMax + (xBlockSize / 2), yMax + (yBlockSize / 2)} fromImage:aImage

–ファイル保存
set outPath to POSIX path of (choose file name with prompt "PNG画像の保存ファイル名を指定してください（拡張子入力必須）")
saveImageRepAtPathAsPNG(cImage, outPath) of me

on calcMin(aLabel as string, nArray)
　　set aStr to "@min." & aLabel
　　set aRes to nArray’s valueForKeyPath:aStr
　　return aRes as anything
end calcMin

on calcMax(aLabel as string, nArray)
　　set aStr to "@max." & aLabel
　　set aRes to nArray’s valueForKeyPath:aStr
　　return aRes as anything
end calcMax

–指定サイズの画像を作成し、指定色で塗ってファイル書き出し
on makeNSImageWithFilledWithColor(aWidth, aHeight, fillColor)
　　set retinaF to (NSScreen’s mainScreen()’s backingScaleFactor()) as real
　　–>　　2.0 (Retina) / 1.0 (Non Retina)
　　
　　set anImage to current application’s NSImage’s alloc()’s initWithSize:(current application’s NSMakeSize(aWidth, aHeight))
　　anImage’s lockFocus()
　　—
　　set theRect to {{x:0, y:0}, {height:aHeight / retinaF, width:aWidth / retinaF}}
　　set theNSBezierPath to current application’s NSBezierPath’s bezierPath
　　theNSBezierPath’s appendBezierPathWithRect:theRect
　　—
　　fillColor’s |set|() –色設定
　　theNSBezierPath’s fill() –ぬりつぶし
　　—
　　anImage’s unlockFocus()
　　—
　　return anImage
end makeNSImageWithFilledWithColor

on cropNSImageTo:{x1, y1, x2, y2} fromImage:theImage
　　set newWidth to x2 – x1
　　set newHeight to y2 – y1
　　set theSize to (theImage’s |size|()) as record
　　set oldHeight to height of theSize
　　
　　— transpose y value for Cocoa coordintates
　　set y1 to oldHeight – newHeight – y1
　　set newRect to {{x:x1, y:y1}, {width:newWidth, height:newHeight}}
　　
　　theImage’s lockFocus()
　　set theRep to NSBitmapImageRep’s alloc()’s initWithFocusedViewRect:newRect
　　theImage’s unlockFocus()
　　
　　set outImage to NSImage’s alloc()’s initWithSize:(theRep’s |size|())
　　outImage’s addRepresentation:theRep
　　
　　return outImage
end cropNSImageTo:fromImage:

–NSImageを指定の大きさでトリミング
on cropNSImageBy:{x1, y1, newWidth, newHeight} fromImage:theImage
　　set theSize to (theImage’s |size|()) as record
　　set oldHeight to height of theSize
　　
　　— transpose y value for Cocoa coordintates
　　set y1 to oldHeight – newHeight – y1
　　set newRect to {{x:x1, y:y1}, {width:newWidth, height:newHeight}}
　　
　　theImage’s lockFocus()
　　set theRep to NSBitmapImageRep’s alloc()’s initWithFocusedViewRect:newRect
　　theImage’s unlockFocus()
　　
　　set outImage to NSImage’s alloc()’s initWithSize:(theRep’s |size|())
　　outImage’s addRepresentation:theRep
　　
　　return outImage
end cropNSImageBy:fromImage:

–画像を指定パスにPNG形式で保存
on saveImageRepAtPathAsPNG(anImage, outPath)
　　set imageRep to anImage’s TIFFRepresentation()
　　set aRawimg to NSBitmapImageRep’s imageRepWithData:imageRep
　　
　　–パスのチルダ展開処理
　　set pathString to NSString’s stringWithString:outPath
　　set newPath to pathString’s stringByExpandingTildeInPath()
　　
　　set myNewImageData to (aRawimg’s representationUsingType:(NSPNGFileType) |properties|:(missing value))
　　return (myNewImageData’s writeToFile:newPath atomically:true) as boolean
end saveImageRepAtPathAsPNG