ImageGear for C and C++ on Windows v19.1 - Updated
Buffer Image Data
User Guide > How to Work with... > Common Operations > Scanning > ISIS Scanning > More ISIS Characteristics > Buffer Image Data

Because of the way ISIS is designed, data is not copied from buffer to buffer as it moves from one driver to the next. Most ISIS drivers share a common buffer and each driver gets a FAR pointer to it. ISIS drivers that do compression and decompression are carefully designed not to modify this common buffer.