Flash 克服闪光波形性能问题的建议
我的问题是下面这个问题的后续问题,但我认为最好开始一个新问题 因此,我在flash中有一个波形绘制实现,它从mp3中提取pcm数据,并在多个缩放级别上绘制波形。它工作得很好,直到你开始处理超过几分钟的音轨,然后它就太慢了。所以我想要一个更快的解决方案 我第一次想到尝试使用pixel bender,因为我听说它计算速度非常快。这是真的,但正如上面的链接所示,缺少for循环使该技术成为不合适的候选技术 所以现在我在想什么是最好的选择 用c语言编写波形计算代码并使用炼金术是否可以提高速度和性能?它基本上还是在运行,对吗 使用某种服务器端脚本会更好吗?也许将pcm数据作为bytearray传递给php脚本,并让脚本返回绘图数据 你能想到我可以尝试研究的其他技术吗 编辑:>> 我在as3中尝试做的是 将MP3音频数据提取到字节数组 确定要在最大缩放级别打印的虚拟像素数(例如,800像素=2倍缩放时轨迹的10秒) 因此,如果我的采样数=33315840,最大虚拟像素数=1600(需要滚动,因为我的视口是800像素宽),那么我的块大小= 33315840/1600=20822 因此,对于bytearray中的每20822个样本,我找到最大值,并将该值用作绘图值 编辑2 @回忆录 我想了想你在哪里提出的观点,这似乎比整个max业务更明智 我已经完成了以下代码,我认为它代表了您所说的内容。 一个问题是,如果我将分辨率改为大于800,我会得到非常高的线和非常短的线,这看起来非常奇怪。在800它是一个非常好的波形 如果我的分辨率超过1600,我会在尝试绘制rect时抛出错误,指出参数无效 我想我对你的缩放策略有点困惑。你说“如果你放大,你用一个重复的分辨率重新绘制波形”。 我真的不明白你是什么意思?我知道我一次只能画800像素。假设我进行2倍缩放,这是否意味着我将样本源的读取量加倍,并有1600个打印点,但根据滚动位置一次仅绘制800个打印点Flash 克服闪光波形性能问题的建议,flash,performance,alchemy,Flash,Performance,Alchemy,我的问题是下面这个问题的后续问题,但我认为最好开始一个新问题 因此,我在flash中有一个波形绘制实现,它从mp3中提取pcm数据,并在多个缩放级别上绘制波形。它工作得很好,直到你开始处理超过几分钟的音轨,然后它就太慢了。所以我想要一个更快的解决方案 我第一次想到尝试使用pixel bender,因为我听说它计算速度非常快。这是真的,但正如上面的链接所示,缺少for循环使该技术成为不合适的候选技术 所以现在我在想什么是最好的选择 用c语言编写波形计算代码并使用炼金术是否可以提高速度和性能?它基
private function calculatePlottingData():void
{
this._container=new UIComponent()
drawon=new MovieClip()
_container.addChild(drawon)
addChild(_container)
var spriteSize:Number;
spriteSize=800; // my resolution
//ba is a bytearray filled with my extracted audio data
//blocksize helps me determine where in the bytearray
//to read a sample value from for plotting
blocksize=Math.floor(ba.length / spriteSize);
var tstart:Number=getTimer()
var l:Number
var r:Number
var la:Number
var ra:Number
var readpoint:int=0;
var val:Number;
for (var i:int=0; i < spriteSize; i++)
{
readpoint=i * blocksize
ba.position=readpoint;
//read teh left and right sample
la=ba.readFloat();
ra=ba.readFloat();
val=(la + ra) / 2;
plottingvalues[i]=val
drawon.graphics.beginFill(0xff0000)
}
var tend:Number=getTimer() - tstart;
trace("time taken=" + tend / 1000)
draw()
}
private function draw():void
{
var val:Number
for (var i:int=0; i < _viewportwidth; i++)
{
drawon.graphics.beginFill(0xffffff)
val=plottingvalues[i];
drawon.graphics.drawRect(i, 50, 1, val * 50)
}
}
私有函数calculatePlottingData():void
{
此.\u容器=新UIComponent()
drawon=新电影剪辑()
_container.addChild(drawin)
addChild(_容器)
变量spriteSize:数字;
spriteSize=800;//我的分辨率
//ba是一个字节数组,其中填充了我提取的音频数据
//blocksize帮助我确定bytearray中的位置
//从中读取样本值以进行打印的步骤
blocksize=数学地板(ba.length/spriteSize);
var tstart:Number=getTimer()
变量l:数字
var:数字
var la:数字
var ra:数字
变量读取点:int=0;
var-val:数字;
for(变量i:int=0;i
编辑3>基于仅获得800个打印点的改进代码
对于我来说,这段代码看起来足够快。使用@backtodos建议坚持一个解决方案,可以节省大量处理时间
package drawing
{
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.MovieClip;
import flash.events.MouseEvent;
import flash.geom.Rectangle;
import flash.media.Sound;
import flash.utils.ByteArray;
import flash.utils.getTimer;
import mx.core.Application;
public class WaveformView extends MovieClip
{
private var _sound:Sound
private var _resolution:Number
private var _quality:int=1;
private var _buffersize:int;
private var _ba:ByteArray=new ByteArray()
private var _step:Number
private var _zoomby:int=1;
private var _zoomfactor:int=2;
private var _blocksize:int;
private var _scrollbar:Bitmap
private var _scrollthumb:MovieClip
private var _relativeThumbPosition:Number=0
private var _sliderRange:int
private var _sliderCenterMinLeft:int
private var _sliderCenterMax_Right:int;
public var _slider_rel_pos:Number=0;
private var _sliderCenter:Number=0;
public function WaveformView(snd:Sound, res:Number=800, quality:int=2, buffersize:int=2048)
{
super();
this._sound=snd;
this._resolution=res;
this._quality=quality; // not implemented yet
this._buffersize=buffersize;
initScrollBar();
getPCM()
drawwaveform()
}
private function initScrollBar():void
{
var sbbmd:BitmapData=new BitmapData(_resolution, 20, false, 0xcccccc)
_scrollbar=new Bitmap(sbbmd)
_scrollbar.y=120
addChild(_scrollbar)
sbbmd=new BitmapData(_resolution, 16, false, 0xeeeeee)
_scrollthumb=new MovieClip()
_scrollthumb.graphics.beginFill(0xff0000)
_scrollthumb.graphics.drawRect(0, 0, _resolution, 10)
_scrollthumb.graphics.endFill()
_scrollthumb.y=125
addChild(_scrollthumb)
_scrollthumb.buttonMode=true
_scrollthumb.addEventListener(MouseEvent.MOUSE_DOWN, beginthumbdrag)
}
private function beginthumbdrag(e:MouseEvent):void
{
_scrollthumb.startDrag(false, new Rectangle(_scrollbar.x, _scrollbar.y + 5, _scrollbar.width - (_scrollthumb.width), 0))
_scrollthumb.addEventListener(MouseEvent.MOUSE_MOVE, shuttleMoving, false, 0, true);
_scrollthumb.addEventListener(MouseEvent.MOUSE_UP, endthumbdrag, false, 0, true);
}
private function endthumbdrag(e:MouseEvent):void
{
_scrollthumb.stopDrag();
e.updateAfterEvent();
_scrollthumb.removeEventListener(MouseEvent.MOUSE_MOVE, shuttleMoving);
}
private function shuttleMoving(e:MouseEvent):void
{
calculateShuttleRelativePosition();
drawwaveform()
e.updateAfterEvent()
}
private function calculateShuttleRelativePosition():void
{
var _x:Number=_scrollthumb.x
_sliderCenter=_x + (_scrollthumb.width / 2)
_sliderRange=_scrollbar.width - _scrollthumb.width;
_slider_rel_pos=(_sliderCenter - _sliderCenterMinLeft) / _sliderRange
}
public function getPCM():void
{
var len:int=_sound.length * 44.1
_sound.extract(_ba, len)
this._blocksize=_ba.length / (_resolution * _zoomby)
shaveblocksize()
}
public function zoomin():void
{
if (this._zoomby < 16)
{
this._zoomby*=2
resizeThumb()
drawwaveform()
}
}
public function zoomout():void
{
if (_zoomby >= 2)
{
this._zoomby/=2
resizeThumb()
drawwaveform()
}
}
private function resizeThumb():void
{
_scrollthumb.width=_scrollbar.width / _zoomby
if (_scrollthumb.width == _resolution)
{
_slider_rel_pos=0
}
_sliderCenterMinLeft=_scrollthumb.width / 2;
_sliderCenterMax_Right=_scrollbar.width - (_scrollthumb.width / 2);
_sliderRange=_scrollbar.width - _scrollthumb.width;
_sliderRange=_scrollbar.width - _scrollthumb.width;
_scrollthumb.x=(_slider_rel_pos * _sliderRange)
}
public function drawwaveform():void
{
var starttime:Number=getTimer()
var readposition:int
var l:Number
var r:Number
var p:Number
this._blocksize=_ba.length / (_resolution * _zoomby)
shaveblocksize()
this.graphics.clear()
this.graphics.beginFill(0xc5c5c5, 0.5)
this.graphics.drawRect(0, 50, _resolution, 1)
var max:int=_ba.length - (_blocksize * _resolution)
var pos:int=Formulas.interpolate(_slider_rel_pos, 0, max)
_ba.position=pos
for (var i:int=0; i < _resolution; i++)
{
l=Math.abs(_ba.readFloat());
r=Math.abs(_ba.readFloat());
l*=50
r*=50
p=(l + r)/2
try
{
this.graphics.drawRect(i, 50, 1, p)
this.graphics.drawRect(i, 50, 1, -p)
}
catch (e:Error)
{
}
_ba.position+=_blocksize
}
}
private function shaveblocksize():void
{
do
{
_blocksize--
} while (_blocksize % 4);
}
}
}
包装图
{
导入flash.display.Bitmap;
导入flash.display.BitmapData;
导入flash.display.MovieClip;
导入flash.events.MouseEvent;
导入flash.geom.Rectangle;
导入flash.media.Sound;
导入flash.utils.ByteArray;
导入flash.utils.getTimer;
导入mx.core.Application;
公共类waveormview扩展了MovieClip
{
私人音效:音效
私有变量解析:数字
私人var_质量:int=1;
私有变量_buffersize:int;
私有变量:ByteArray=newbytearray()
私有变量\u步骤:编号
私有变量_zoomby:int=1;
私有变量_zoomfactor:int=2;
私有变量块大小:int;
私有变量\u滚动条:位图
私有变量:MovieClip
私有变量_relativeThumbPosition:Number=0
私有变量_slideerrage:int
private var\u sliderCenterMinLeft:int
私有变量sliderCenterMax\u Right:int;
公共变量滑块位置:编号=0;
private var_sliderCenter:Number=0;
公共功能波形视图(snd:Sound,res:Number=800,quality:int=2,buffersize:int=2048)
{
超级();
这个。_sound=snd;
这个。_分辨率=分辨率;
这个。_quality=quality;//尚未实现
这个。_buffersize=buffersize;
package drawing
{
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.MovieClip;
import flash.events.MouseEvent;
import flash.geom.Rectangle;
import flash.media.Sound;
import flash.utils.ByteArray;
import flash.utils.getTimer;
public class WaveformView extends MovieClip
{
private var _sound:Sound
private var _resolution:Number
private var _quality:int=1;
private var _buffersize:int;
private var _ba:ByteArray=new ByteArray()
private var _zoomby:int=1;
private var _zoomXFactor:int=2;
private var _maximumSecondsPerViewPort:int=10;
;
private var _blocksize:int;
private var _scrollbar:Bitmap
private var _scrollthumb:MovieClip
private var _relativeThumbPosition:Number=0
private var _sliderRange:int
private var _sliderCenterMinLeft:int
private var _sliderCenterMax_Right:int;
public var _slider_rel_pos:Number=0;
private var _sliderCenter:Number=0;
private var _resolutions:Array
private var _zoomsInSecondsArray:Array=new Array();
private var _numberOfZoomLevels:int;
public function WaveformView(snd:Sound, res:Number=800, quality:int=2, buffersize:int=2048, height:int=100)
{
super();
this._sound=snd;
this._resolution=res;
this._quality=quality; // not implemented yet
this._buffersize=buffersize;
// addChild(viewportBitmap)
_resolutions=new Array()
initScrollBar();
getPCM()
calculateZoomLevelData()
drawwaveform()
}
public function calculateZoomLevelData():void
{
_zoomsInSecondsArray=[]
var amt:int=Math.round(_sound.length / 1000);
_zoomsInSecondsArray.push(amt);
while (amt >= _maximumSecondsPerViewPort)
{
amt=amt / _zoomXFactor;
if (amt >= _maximumSecondsPerViewPort)
{
_zoomsInSecondsArray.push(amt);
}
}
_numberOfZoomLevels=_zoomsInSecondsArray.length;
var checkSize:int=_resolution;
var r:ResolutionCache
r=new ResolutionCache(checkSize)
_resolutions.push(r)
for (var c:int=1; c < _numberOfZoomLevels + 1; c++)
{
checkSize=checkSize * _zoomXFactor;
r=new ResolutionCache(checkSize)
_resolutions.push(r)
}
_resolutions.pop()
}
private function initScrollBar():void
{
var sbbmd:BitmapData=new BitmapData(_resolution, 20, false, 0xcccccc)
_scrollbar=new Bitmap(sbbmd)
_scrollbar.y=120
addChild(_scrollbar)
sbbmd=new BitmapData(_resolution, 16, false, 0xeeeeee)
_scrollthumb=new MovieClip()
_scrollthumb.graphics.beginFill(0xff0000)
_scrollthumb.graphics.drawRect(0, 0, _resolution, 10)
_scrollthumb.graphics.endFill()
_scrollthumb.y=125
addChild(_scrollthumb)
_scrollthumb.buttonMode=true
_scrollthumb.addEventListener(MouseEvent.MOUSE_DOWN, beginthumbdrag)
}
private function beginthumbdrag(e:MouseEvent):void
{
_scrollthumb.startDrag(false, new Rectangle(_scrollbar.x, _scrollbar.y + 5, _scrollbar.width - (_scrollthumb.width), 0))
_scrollthumb.addEventListener(MouseEvent.MOUSE_MOVE, shuttleMoving, false, 0, true);
_scrollthumb.addEventListener(MouseEvent.MOUSE_UP, endthumbdrag, false, 0, true);
}
private function endthumbdrag(e:MouseEvent):void
{
_scrollthumb.stopDrag();
e.updateAfterEvent();
_scrollthumb.removeEventListener(MouseEvent.MOUSE_MOVE, shuttleMoving);
}
private function shuttleMoving(e:MouseEvent):void
{
calculateShuttleRelativePosition();
drawwaveform()
//e.updateAfterEvent()
}
private function calculateShuttleRelativePosition():void
{
var _x:Number=_scrollthumb.x
_sliderCenter=_x + (_scrollthumb.width / 2)
_sliderRange=_scrollbar.width - _scrollthumb.width;
_slider_rel_pos=(_sliderCenter - _sliderCenterMinLeft) / _sliderRange
}
public function getPCM():void
{
var len:int=_sound.length * 44.1
_sound.extract(_ba, len)
this._blocksize=_ba.length / (_resolution * _zoomby)
shaveblocksize()
}
public function zoomin():void
{
if (this._zoomby < 16)
{
this._zoomby*=2
resizeThumb()
drawwaveform()
}
}
public function zoomout():void
{
if (_zoomby >= 2)
{
this._zoomby/=2
resizeThumb()
drawwaveform()
}
}
private function resizeThumb():void
{
_scrollthumb.width=_scrollbar.width / _zoomby
if (_scrollthumb.width == _resolution)
{
_slider_rel_pos=0
}
_sliderCenterMinLeft=_scrollthumb.width / 2;
_sliderCenterMax_Right=_scrollbar.width - (_scrollthumb.width / 2);
_sliderRange=_scrollbar.width - _scrollthumb.width;
_sliderRange=_scrollbar.width - _scrollthumb.width;
_scrollthumb.x=(_slider_rel_pos * _sliderRange)
}
private function getResolutionCache(vww:int):ResolutionCache
{
var r:ResolutionCache
for (var i:int=0; i < _resolutions.length; ++i)
{
if (_resolutions[i].name == vww)
{
r=_resolutions[i];
break;
}
}
return r;
}
public function drawwaveform():void
{
var starttime:Number=getTimer()
var readposition:int
var viewPortWidth:int=_resolution;
var virtualWindowWidth:int=_resolution * _zoomby;
var l:Number
var r:Number
var p:Number
var rc:ResolutionCache=getResolutionCache(virtualWindowWidth)
this._blocksize=_ba.length / virtualWindowWidth
shaveblocksize()
this.graphics.clear()
this.graphics.beginFill(0xc5c5c5, 0.5)
this.graphics.drawRect(0, 50, _resolution, 1)
var pixel:int=(_slider_rel_pos * (virtualWindowWidth - viewPortWidth - 1));
var readpoint:int=pixel * _blocksize;
var rect:Rectangle
_ba.position=readpoint;
this.graphics.clear()
this.graphics.beginFill(0xffffff)
for (var i:int=0; i < _resolution; i++)
{
if (rc.points[pixel] == -1)
{
_ba.position=pixel * _blocksize
l=_ba.readFloat() * 100;
r=_ba.readFloat() * 100;
p=(l + r) / 2
rc.addPoint(pixel, i, height / 2, p)
rect=rc.points[pixel]
//this.graphics.drawRect(rect.x,rect.y,rect.width,rect.height)
this.graphics.drawRect(i, 50, 1, p)
this.graphics.drawRect(i, 50, 1, -p)
}
else
{
//viewportBitmapdata.fillRect(rc.points[pixel], 0xffffff)
rect=rc.points[pixel]
this.graphics.drawRect(i, 50, 1, rect.height)
this.graphics.drawRect(i, 50, 1, -rect.height)
//this.graphics.drawRect(i,height/2,rect.width,rect.height)
}
pixel++
}
}
private function shaveblocksize():void
{
do
{
_blocksize--
} while (_blocksize % 4);
}
}
}
if (_pcmData.bytesAvailable)
{
var la:Number=_pcmData.readFloat();
var ra:Number=_pcmData.readFloat();
var l:Number=la > 0.0 ? la : -la;
var r:Number=ra > 0.0 ? ra : -ra;
++_divCount;
var ml:Number=0;
var mr:Number=0;
var a_ml:Number=ml > 0.0 ? ml : -ml;
var a_mr:Number=mr > 0.0 ? mr : -mr;
ml=a_ml > (l) ? ml : l;
mr=a_mr > (r) ? mr : r;
}