Resize比較2
画像縮小検証その2です。
今回は2段階縮小法（正式名称不明）を主に検証。
結果は横にならんでいるので、画面外にはみ出てたらドラッグして確認してください。
前回↓ではpixelbender利用のリサイズはイマイチだったので省略。（縮小用に最適化されてないのかもしれませんが）
http://wonderfl.net/c/dJ7M
他にも処理速度の問題もあり、別を探っていたら2段階縮小という方法があったので試してみると、なかなか綺麗で、それなりに早く、仕組も簡単、と上々の結果になりました。
処理速度については、Lanczos法の有無を選べるようにしてあるので、scaleを大き目にして比べてみてください。
元々リサイズAIRアプリ↓を作ろうとして調べてたのですが、2段階縮小法を使ってようやく形になりました。
http://mrsz.tsukuenoue.com/
/**
* Copyright foka ( http://wonderfl.net/user/foka )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/pXpl
*/
package
{
import com.bit101.components.InputText;
import com.bit101.components.Label;
import com.bit101.components.PushButton;
import com.bit101.components.HUISlider;
import com.bit101.components.ComboBox;
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.Loader;
import flash.display.Sprite;
import flash.events.Event;
import flash.events.MouseEvent;
import flash.net.URLRequest;
import flash.system.LoaderContext;
import flash.system.Security;
import flash.ui.Mouse;
import flash.ui.MouseCursor;
public class Main extends Sprite
{
private var souceBitmapData:BitmapData;
private var targetScale:Number;
private var container:Sprite = new Sprite();
private var pushbutton:PushButton;
private var loader:Loader = new Loader();
private var slider:HUISlider;
private var comboBox:ComboBox;
private var LanchozFlg:Boolean = true;
/*------------------------------------------------
コンストラクタ
------------------------------------------------*/
public function Main():void {
Security.loadPolicyFile("http://data.tsukuenoue.com/crossdomain.xml");
var context:LoaderContext = new LoaderContext(true);
loader.contentLoaderInfo.addEventListener(Event.COMPLETE, onLoadComplete);
loader.load(new URLRequest("http://data.tsukuenoue.com/resize/fusya.jpg"),context);
addChild(container);
}
/*------------------------------------------------
イベント
------------------------------------------------*/
private function onLoadComplete(e:Event):void
{
pushbutton = new PushButton(this, 185, 4, "resize", onClick);
slider = new HUISlider(this, 5, 5,"scale");
slider.maximum = 1;
slider.minimum = 0.01;
slider.labelPrecision = 2;
slider.value = 0.3;
var selectArray:Array = ["TwoStep + Lanczos + Normal", "Twostep + Normal"];
comboBox = new ComboBox(this, 300, 4, selectArray[0], selectArray);
comboBox.width = 160;
comboBox.addEventListener(Event.SELECT, onBoxSelect);
loader.x = 8;
loader.y = 40;
addChild(loader);
souceBitmapData =Bitmap(loader.content).bitmapData;
container.x =8;
container.y =40;
container.addEventListener(MouseEvent.MOUSE_DOWN, onDn);
container.addEventListener(MouseEvent.ROLL_OVER, onOver);
container.addEventListener(MouseEvent.ROLL_OUT, onOut);
}
private function onBoxSelect(e:Event):void
{
if (comboBox.selectedIndex == 0) {
LanchozFlg = true;
}else {
LanchozFlg = false;
}
resize();
}
private function onOver(e:MouseEvent):void
{
Mouse.cursor = MouseCursor.HAND;
}
private function onOut(e:MouseEvent):void
{
Mouse.cursor = MouseCursor.AUTO;
}
private function onDn(e:MouseEvent):void
{
stage.addEventListener(MouseEvent.MOUSE_UP, onUP);
container.startDrag();
}
private function onUP(e:MouseEvent):void
{
stage.removeEventListener(MouseEvent.MOUSE_UP, onUP);
container.stopDrag();
}
private function onClick(e:MouseEvent):void
{
resize();
}
/*------------------------------------------------
メソッド
------------------------------------------------*/
private function resize():void {
//targetScale = Number(inputText.text);
targetScale = slider.value;
if(targetScale>0){
reset();
loader.visible = true;
twoStepScaleResampling();
if(LanchozFlg){
LanczosResampleing();
}
flashScaleResampling();
loader.visible = false;
}
}
private function twoStepScaleResampling():void {
var returnBmpData:BitmapData = TwoStepResizer.resize(souceBitmapData, Math.round(loader.width*targetScale), Math.round(loader.height*targetScale));
var bmp:Bitmap = new Bitmap(returnBmpData);
container.addChild(bmp);
var label:Label = new Label(container, bmp.x, bmp.height + 5,"TwoStepResize");
}
private function LanczosResampleing():void {
var returnBmpData:BitmapData = LanczosBitmapDataResizer.resize(souceBitmapData, Math.round(loader.width*targetScale), Math.round(loader.height*targetScale));
var bmp:Bitmap = new Bitmap(returnBmpData);
container.addChild(bmp);
bmp.x = Math.round((loader.width * targetScale + 20)*1);
var label:Label = new Label(container, bmp.x, bmp.height + 5,"Lanczos");
}
private function flashScaleResampling():void {
var bmp:Bitmap = new Bitmap(souceBitmapData);
bmp.smoothing = true;
var bmpContainer:Sprite = new Sprite();
container.addChild(bmpContainer);
bmpContainer.addChild(bmp);
bmp.scaleX = bmp.scaleY = targetScale;
if(LanchozFlg){
bmpContainer.x = Math.round((loader.width * targetScale + 20) *2);
}else {
bmpContainer.x = Math.round((loader.width * targetScale + 20) * 1);
}
var label:Label = new Label(container, bmpContainer.x, bmpContainer.height + 5,"FlashNormalScale");
}
private function reset():void {
while (container.numChildren > 0) {
container.removeChildAt(0);
}
container.x =8;
container.y =40;
}
}
}
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.DisplayObject;
import flash.display.Sprite;
import flash.filters.BlurFilter;
import flash.utils.Dictionary;
class TwoStepResizer
{
/*
* 2段階縮小
*
* */
//resize
static public function resize(bmpdata:BitmapData, w:uint, h:uint,blur:Number=0,sizeChk:Boolean=true):BitmapData {
if (sizeChk&&bmpdata.width > w * 2 || sizeChk&&bmpdata.height > h*2) {
bmpdata = resize(bmpdata,w*2,h*2,0,false);
}
var targetScale:Number = Math.min(w / bmpdata.width,h / bmpdata.height);
var bmp:Bitmap = new Bitmap(bmpdata.clone());
bmp.smoothing = true;
bmp.scaleX = bmp.scaleY = targetScale;
//必要があればぼかして調整
if(blur>0){
bmp.filters = [new BlurFilter(1.05, 1.05, blur)];
}
var container:Sprite = new Sprite();
container.addChild(bmp);
var outputBmpData:BitmapData = new BitmapData(container.width, container.height,true,0);
outputBmpData.draw(container);
container.removeChild(bmp);
container = null;
bmp.bitmapData.dispose();
bmp = null;
return outputBmpData;
}
//BitmapData化
static public function setBmpData(mc:DisplayObject):BitmapData {
var bmpdata:BitmapData = new BitmapData(mc.width, mc.height, true, 0);
bmpdata.draw(mc);
return bmpdata;
}
}
class LanczosBitmapDataResizer
{
/*
* 以下、Jozef Chutka氏のLanczos Resamplingを使わせて頂きました
* http://wonderfl.net/c/dLf0
*
* */
public static var CACHE:Dictionary;
public static var CACHE_PRECISION:uint = 100;
public static var FILTER_SIZE:uint = 1;
public function LanczosBitmapDataResizer()
{
}
public static function kernel(filterSize:uint, x:Number):Number
{
if(x >= filterSize || x <= -filterSize)
return 0;
if(x == 0)
return 1;
var xpi:Number = x * Math.PI;
return filterSize * Math.sin(xpi) * Math.sin(xpi / filterSize)
/ (xpi * xpi);
}
public static function createCache(kernel:Function,
cachePrecision:uint, filterSize:uint):Dictionary
{
var cache:Dictionary = new Dictionary();
var max:uint = filterSize * filterSize * cachePrecision;
var iPrecision:Number = 1 / cachePrecision;
var value:Number;
for(var cacheKey:uint = 0; cacheKey < max; cacheKey++)
{
value = kernel(filterSize, Math.sqrt(cacheKey * iPrecision));
cache[cacheKey] = value < 0 ? 0 : value;
}
return cache;
}
public static function resize(source:BitmapData, width:uint, height:uint, kernel:Function=null):BitmapData
{
var total:Number, distanceY:Number, value:Number;
var a:Number, r:Number, g:Number, b:Number;
var i:uint, color:uint, cacheKey:uint;
var x:int, x1:uint, x1b:int, x1e:int;
var y:int, y1:uint, y1b:int, y1e:int, y2:uint, y3:uint;
var y1et:Number, x1et:Number;
var values:Vector.<Number> = new Vector.<Number>();
var sx:Number = width / source.width;
var sy:Number = height / source.height;
var sw1:uint = source.width - 1;
var sh1:uint = source.height - 1;
var isx:Number = 1 / sx;
var isy:Number = 1 / sy;
var cw:Number = 1 / width;
var ch:Number = 1 / height;
var csx:Number = Math.min(1, sx) * Math.min(1, sx);
var csy:Number = Math.min(1, sy) * Math.min(1, sy);
var cx:Number, cy:Number;
var sourcePixelX:Number, sourcePixelY:Number;
var sourcePixels:Vector.<uint> = source.getVector(source.rect);
var output:BitmapData =
new BitmapData(width, height, source.transparent);
var outputPixels:Vector.<uint> =
new Vector.<uint>(width * height, true);
var cache:Dictionary = CACHE;
var cachePrecision:uint = CACHE_PRECISION;
var filterSize:uint = FILTER_SIZE;
var kernel:Function = kernel || public::kernel;
if(!cache)
CACHE = cache = createCache(kernel, cachePrecision, filterSize);
y = height;
while(y--)
{
sourcePixelY = (y + 0.5) * isy;
y1b = sourcePixelY - filterSize;
if(y1b < 0)
y1b = 0;
y1e = y1et = sourcePixelY + filterSize;
if(y1e != y1et)
y1e = y1et + 1;
if(y1e > sh1)
y1e = sh1;
cy = y * ch - sourcePixelY;
y3 = y * width;
x = width;
while(x--)
{
sourcePixelX = (x + 0.5) * isx;
x1b = sourcePixelX - filterSize;
if(x1b < 0)
x1b = 0;
x1e = x1et = sourcePixelX + filterSize;
if(x1e != x1et)
x1e = x1et + 1;
if(x1e > sw1)
x1e = sw1;
cx = x * cw - sourcePixelX;
values.length = i = total = 0;
for(y1 = y1b; y1 <= y1e; y1++)
{
distanceY = (y1 + cy) * (y1 + cy) * csy;
for(x1 = x1b; x1 <= x1e; x1++)
{
total += values[uint(i++)] = cache[uint(
((x1 + cx) * (x1 + cx) * csx + distanceY)
* cachePrecision)]||0;
}
}
total = 1 / total;
i = a = r = g = b = 0;
for(y1 = y1b; y1 <= y1e; y1++)
{
y2 = y1 * source.width;
for(x1 = x1b; x1 <= x1e; x1++)
{
color = sourcePixels[uint(y2 + x1)];
value = values[uint(i++)] * total;
a += (color >> 24 & 0xff) * value;
r += (color >> 16 & 0xff) * value;
g += (color >> 8 & 0xff) * value;
b += (color & 0xff) * value;
}
}
outputPixels[uint(x + y3)] = a << 24 | r << 16 | g << 8 | b;
}
}
output.setVector(output.rect, outputPixels);
return output;
}
}