The described technology has been initially realized by RasterEdit (since beginning 1997), then SuperEdit version 1.3 (since December 1998). Since December 1999 version 2.1 has been installed. It is much better then the previous one. Here is the customer list of most crutial improvements introduced in the new version:

support for editing point entities;

support for editing large raster image files (larger than 32K pixels);

improvements of user interface in calibration command;

vector snap.
A support for SHP -> DXF conversion is still required.