JPEG Network Graphics
JPEG Network Graphics (acronym JNG ) is a sub- format of MNG that contains JPEG data.
The JNG file format was originally introduced as a sub-format of the MNG animation format, but can be used for stand-alone files with the extension .jng . Version 1.0 of the specification was released on January 31, 2001. However, it is not a W3C recommendation or an ISO standard.
Unlike JPEG, however, JNG can also save a transparency channel ( alpha channel ), which in turn can be embedded losslessly as a 1-, 2-, 4-, 8- or 16-bit PNG data stream, or from a lossy 8-bit data stream. JPEG data stream can exist. Since Bittiger 12 for color information 8- or JPEG data stream can be stored, the latter are (like JPEG) lossy course - that is, every time you save go through the compression image information (and quality) lost. It is also possible to store an 8-bit data stream together with a 12-bit data stream so that decoders who cannot (or do not want to) process the higher-quality information can fall back on the lower-value information if necessary.
JNG offers some other improvements such as: B. color and gamma correction, embedded color profiles, checksums for each segment, metadata, etc.
Programs that support the MNG format can usually also decode the JNG format. Konqueror , for example, offers native MNG / JNG support.
JNG does not have a registered MIME type , but image / x-jng is used unofficially .
See also
Web links
- Description of the JNG format (Version 1.0) (English)
- Photoshop plug-in (for Photoshop 7.0 or larger) (ZIP file; 119 kB)