JPE is the graphic format of the raster image category. It was developed by the standards committee of the Joint Photographic Experts Group. It is a 24-bit compressed graphics format. Typically, it is used for web resources. In most cases, it is used for photographs or images in which there are many colors. Also well suited for many digital cameras to store digital photos. Images that have this extension use lossy compression. And because the quality of individual photos is getting worse. The greater the compression, the less quality the image becomes. The purpose of JPE files is to compress photorealistic images with small color losses. Provides the ability to achieve high compression ratios. We emphasize that usually the maximum compression of graphic information leads to some loss of information. That is, the compression algorithm changes the original data so that the image that is obtained after restoration will be different from the original image, that is, compressed. This compression method is used to work with full-color images that have high photographic quality. During compression, the Discrete-Cosine Transform (DCT), Huffman’s Code quantization and coding are used.
PCX is one of the first bitmap image formats developed by ZSoft for the PC Paintbrush program. This is the original bitmap format for the DOS / Windows platform. It supports monochrome single-bit black and white images, an eight-bit gray scale, indexed color images, and full-color 24-bit RGB model images. But there is no support for additional color and alpha channels, clipping paths, color management. The format provides for the application of the simplest compression algorithm (RLE) so that information is not lost. Now it has a purely historical significance. The PCX file format has been replaced by newer image formats. However, the format is still used in separate applications in order to scan and send faxes. PCX multi-page fax documents use the .DCX extension. Most DOS-based programs are suitable for viewing PCX (PC eXchange) files. In particular, the viewer Norton Commander. The big drawback of the PCX format is that it has too many versions. This can be explained by the fact that the PCX standard is open, and therefore it has been widely used by most independent software developers. And therefore it is constantly updated.