JPF is a raster image category file format that is the successor to the .JPEG image format. Like some other file name extensions (.jpx, .jp2, .j2k), the .jpf extension refers to the JPEG 2000 image format. It is needed to designate the JPEG 2000 Image file type. And JPEG 2000 files are an international standard (ISO / IEC 15444) bitmap format. It was developed by the Joint Photographic Experts Group, JPEG. It serves as a good replacement for the JPEG standard, which is older, but, as before, is in demand and widespread. Compared to JPEG in JPF format, wavelet compression is used, due to the alpha channel transparency is supported, as well as a variety of color models. Also, compared to JPEG, this format provides better scalability of images, provides the ability to achieve smaller file sizes and have a higher level of quality. The format is able to combine compression with losses and without losses. Provides support for image transparency and additional metadata information. It can be viewed in QuickTime Player 7, as in recent versions of Photoshop, provided that the JPEG2000.8bi plugin is installed. Many images also have the extension .JP2 or .JPX.
JNX is a raster map format. It refers to the so-called tile formats, by which you need to understand a large-scale raster image on the map, divided into smaller rectangular parts. This is necessary so that the display of the navigator is accelerated. JNX files are used on Garmin devices to display satellite maps that are available through BirdsEye subscription. In devices for these files, space is allocated on the internal drive in the Garmin \ BirdsEye folder or on the SD card. The coordinates are stored in the form of signed 4-byte integers. The coordinates of the two corners of the map describe two pairs of numbers: one is latitude, the second is longitude. Tiles are standard JPG drawings. Their lion's share in BirdsEye cards is with a resolution of 256 by 256 pixels. There is support for images and larger. Devices are endowed with the ability to display tiles up to 1 megapixel in size. If the sizes go beyond this limit, then the image is automatically reduced with a loss of quality. There is a significant limitation of the JNX format. Such is the rigid binding of cards to a specific device. The JNX format is fully explored. An exception is only part of the loader service data block. However, when you create your own maps, this can be neglected. There is a set of utilities with which you can convert raster maps to JNX format. They serve for reverse conversion. Files in the JNX format have a binding code for the device. Despite this, there are ways to use your own JNX cards in Garmin navigators.