kdu_codestream::access_siz

Associated with the internal code-stream management machinery (and hence with every non-empty kdu_codestream interface) is a unique siz_params object, which is the head (or root) of the entire network of coding parameters associated with the relevant code-stream. These concepts are discussed in the description of the kdu_params object.

Because the returned object provides access to the entire network of kdu_params-derived objects relevant to the code-stream, the caller may use the returned pointer to parse command-line arguments (see kdu_params::parse_string), copy parameters between code-streams (see kdu_params::copy_with_xforms) and to explicitly set or retrieve individual parameter values (see kdu_params::set and kdu_params::get), as they appear in code-stream marker segments.

Be careful to note, however, that the kdu_codestream interface and its immediate relatives, kdu_tile, kdu_tile_comp, kdu_resolution, etc., support geometrically transformed views of the underlying compressed image representation. These transformed views are not reflected in the explicit parameter values which might be retrieved or configured directly using the various member functions offered by kdu_params. For this reason, you are generally advised to work with the kdu_codestream functions and those of the related interfaces described here, except where new parameters must be explicitly configured for compression, or modified in a transcoding session.