ImageGear for C and C++ on Windows v19.10 - Updated
Saving JPEG 2000 and JPX Images in Lossless Mode
User Guide > How to Work with... > Formats with Additional Functionality > JPEG 2000 > Saving JPEG 2000 and JPX Images in Lossless Mode

Lossless compression is used in sensitive applications, such as legal or medical. Lossless compression provides lower compression rates than even the maximal quality lossy compression. However, JPEG 2000 lossless compression outperforms comparable lossless image compression techniques like LZW and TIFF. The format also allows storing several quality levels in an image, and in particular, using lossy compression for the lower quality levels and lossless compression for the highest quality layer.

The following actions are necessary to save a lossless JPEG 2000 or JPX image:

If the maximum compression quality is used, the value of QUANT_STEP parameter is ignored, as no quantization takes place.

See JPEG 2000 and JPX file format descriptions for details on the control parameters mentioned above.