A codec cannot really request to do OPT_HDW unless QTW asks it to. Codecs are only permitted to downgrade QTW requests to a less efficient level during PreDecompress. QTW generally (but not always) asks for OPT_HDW first, and then goes to OPT_BMP if the codec recommends the downgrade. Sometimes QTW will ask for OPT_RAW first (for various reasons).
A hardware aware codec will generally need to know the difference between banked and non-banked display adapters (VDSP_QUERYBANK).
A full-featured codec will perform the following:
* Support OPT_HDW for all different BMP_xxx formats (when asked to do so).
* Support OPT_BMP for all different BMP_xxx formats (almost always).
* Support OPT_RAW at different pixel depths (8, 16, 24).