Who knows what features GIF, JPG, NPG and BMP files have?

GIF is a graphic interchange format, which has the following characteristics:

(1)GIF only supports pictures with less than 256 colors;

(2)GIF is stored in lossless compression mode, which can generate very small files without affecting the image quality;

(3) Support transparent color, which can make the image emerge on the background;

(4)GIF files can be animated, which is its most prominent feature. The full name of jpg is JPEG (Joint Photographic Experts Group). It is the first international digital image compression standard for still images formulated by ISO (International Organization for Standardization) and CCITT (International Telephone and Telegraph Advisory Committee), and it is also the most widely used image compression standard so far. JPEG can provide lossy compression, so the compression ratio can reach a level unmatched by other traditional compression algorithms.

Advantages: Photographic works or realistic works support advanced compression. The file size can be controlled by variable compression ratio. Support interleaving (for progressive JPEG files). Extensive support for Internet standards. Because of its small size, jpg is used to store and transmit photo formats on the World Wide Web.

Disadvantages: Lossy compression will reduce the quality of the original image data. When you edit and resave a JPEG file, JPEG will mix the quality of the original picture data. This decline is cumulative. JPEG is not suitable for simple pictures with few colors, similar colors in a large area or obvious brightness difference. PNG is an image file storage format, which aims to replace GIF and TIFF file formats and add some functions that GIF file format does not have. The name of Portable Network Graphics Format (PNG) comes from the unofficial "PNG's Not GIF", which is a bitmap file storage format pronounced "ping". When storing grayscale images with PNG, the depth of grayscale images can be as high as 16 bits, when storing color images, the depth of color images can be as high as 48 bits, and α channel data can also be stored as high as 16 bits. PNG uses lossless data compression algorithm derived from LZ77. Because of its high compression ratio and small file size, it is generally used in JAVA programs, or web pages or S60 programs. BMP is an image file format independent of hardware devices, which is widely used. It uses bitmap storage format and does not use any other compression except image depth, so BMP files take up a lot of space.