DNG is an open-source raster image format developed by Adobe Systems and an extension of the TIFF 6.0 cross-platform universal format. The name of the format is an abbreviation of Digital NeGative Specification. The novelty was announced by the developer in 2004 as a standard format for RAW files. It is large in size because it contains not only the main image of high quality, but also metadata, as well as several images for preview (lower quality and resolution). Digital photos in this format are stored in uncompressed form.
BMP is a graphic format that allows you to store bitmaps as a bitmap based on single-layer rasters. It was developed by Microsoft. She also implemented it in the Windows operating system. The BMP format (English Bitmap Picture) is used in the work of many programs, since its support is integrated into Windows and OS / 2. Files of this format can have the extensions .bmp, .dib or .rle. The BMP graphics format has often changed. From the very beginning, the image structure was built by combining small squares, that is, pixels, each of which is capable of containing data about what color depth is. It happens to be 1, 2, 4, 8, 16, 24, 32, 48 bits per pixel. The size of the final image depends on the bitness. The BMP file format still looks like a monster, since it has large sizes. After all, the image is uncompressed, which can not be said, for example, about the JPG format. Any Windows operating system has the means to open such images. The main editing tool has always been Paint - the native Microsoft program that is in every version of Windows. In BMP, images are stored in their original form, but compression algorithms can also be used. Let's say BMP provides quality support for RLE compression.