The most likely ccd to jpg conversion that works is export of ClickCharts Diagram files (.ccd) to JPEG format, which is possible with the software itself as export to standard graphics is supported by default.
Except for that, ,aybe it's a typo or related to a completely different procedure. Perhaps some users are looking for a way to recover pictures from CloneCD disk images. But .ccd files are just metadata for .img file that actually contain the disk image, so even in this case, it does not work this way.