The methods in ImageReader and ImageWriter that take ImageReadParam and
ImageWriteParam objects (respectively) don't define any action to be taken
if the object is not what they are expecting. In particular, many plug-ins
will only want to deal with objects that have the same set of capabilities
as the ones that are returned from their getDefault{Read,Write}Param factory
methods. For example, a reader that does not support the setting of a source
render size will disable that capability in ImageReadParam objects that it
creates, but may receive "foreign" ImageReadParam objects that claim to
have a source render size already set.

  All methods in ImageReader, ImageWriter, and ImageTranscoder that take
an ImageReadParam or ImageWriteParam should document that they may
ignore optional parameter settings that they do not support (they may
issue a warning via an IIO{Read,Write}WarningListener if they wish).

  The setting of capability flags on ImageReadParam and ImageWriteParam
should be removed from their constructors in order to lessen the chances
of confusion among developers.