flash - How can I set a color to transparency for an import image in AS2 -

how can set color black: 0x000000 transparent, normaly magic pink transparent want set black be.

if don't understand: http://j.imagehost.org/0829/woodygx_0.jpg

i have image, , when converting 80x80 sprite want background transparent, meaning: no background, character.

notice: answer in actionscript 3, in case either decide migrate actionscript 3, moreso other people , general info.

can create new bitmapdata source bitmapdata black pixels removed (converted alpha channel).

i've created function you:

// takes source bitmapdata , converts new bitmapdata, ignoring // dark pixels below specified sensitivity. function removedarkness(source:bitmapdata, sensitivity:uint = 10000):bitmapdata {     // define new bitmapdata, size constraints ensure loop     // doesn't time out / crash.     // demonstration only, consider creating class manages     // portions of bitmapdata @ time (up 50,000 iterations per     // frame) , dispatches event new bitmapdata when done.     var fresh:bitmapdata = new bitmapdata(         math.min(600, source.width),         math.min(400, source.height),         true, 0xffffffff     );      fresh.lock();      // remove listed colors.     for(var v:int = 0; v < fresh.height; v++)     {         for(var h:int = 0; h < fresh.width; h++)         {             // select relevant pixel iteration.             var pixel:uint = source.getpixel(h, v);              // check against colors remove.             if(pixel <= sensitivity)             {                 // match - delete pixel (fill transparent pixel).                 fresh.setpixel32(h, v, 0x00000000);                  continue;             }              // no match, fill expected color.             fresh.setpixel(h, v, pixel);         }     }       // we're done modifying new bitmapdata.     fresh.unlock();       return fresh; } 

as can see, takes:

• bitmapdata want remove darker pixels from.
• uint representing how many shades of black / grey want have removed.

and here's demo using source image:

var original:loader = new loader(); original.load( new urlrequest("http://j.imagehost.org/0829/woodygx_0.jpg") ); original.contentloaderinfo.addeventlistener(event.complete, imageloaded);   // original image has loaded, continue. function imageloaded(e:event):void {     // capture pixels loaded bitmap.     var obmd:bitmapdata = new bitmapdata(original.width, original.height, false, 0);     obmd.draw(original);       // create new bitmapdata without black pixels.     var herosheet:bitmapdata = removedarkness(obmd, 1200000);     addchild( new bitmap(herosheet) ); }