Actionscript 3 library for losslessly reading/writing IPTC and EXIF metadata in JPG/TIFF files.

I need a Actionscript library that can be embedded in a Flash Builder project and provide the following functionality: - read most of the EXIF and IPTC Core metadata from JPG files and be able to write them back without reading the whole image file. - be able to create XMP sidecar files, if desired (a setting to switch on or off XMP generation)