I guess using a matrix to scale it down might do the trick. I haven't tested the code though.
var w:Number = 3264;
var h:Number = 2448;
var scale:Number = w / 2880;
var bmpd:BitmapData = new BitmapData(2880, h / scale, true, 0x00FFFFFF);
var matrix:Matrix = new Matrix();
matrix.createBox(scale, scale)
bmpd.draw(jpgSprite, matrix);
Best Solution
it seems, that xScale and yScale may not exceed 0x8000 ...
size itself also seems to be bound ... i found a limit 0x6666660 ...
here the code:
didn't find any documentation about it ... so you may even get other results on your machine ...
greetz
back2dos