JNG (pronounced jing) is a JPEG-based image file format, closely related to PNG. The name stands for JPEG Network Graphics. Unlike JFIF (the usual JPEG file format), JNG supports transparency. JNG was created as an adjunct to the MNG animation format and is not a widely used as a stand-alone format.
The structure of JNG files is essentially the same as that of PNG files, differing only in the slightly different signature (8B 4A 4E 47 0D 0A 1A 0A in hexadecimal) and the use of different chunks.
JNG does not have a registered MIME media type, but image/x-jng can be used.