Are jpeg and jpg the same?

Jpeg and jpg are the same, there is no difference, they are the same file format. JPEG, the Joint Photographic Experts Group, is a standard for continuous-tone static image compression. The file suffix is ​​".jpg" or ".jpeg" and is the most commonly used image file format.

jpg/jpeg is a lossy compressed image format. The full name of Jpg is Jpeg, which is the abbreviation of Joint Photographic Experts Group. In 1992, the organization released the "JPEG Standard", a standard for image compression.

Image files compressed using the JPEG standard are called "JPEG files". The extensions of such files are usually JPG, JPEG, JPE, JFIF and JIF. Among these file formats, the use of JPG The most extensive.

If JPEG here refers to the Joint Photographic Experts Group, then JPEG and JPG are the relationship between the organization that formulates the compression standard and the format of the image compressed using the compression standard formulated by the organization;

If JPEG refers to the JPEG compression standard, then JPEG and JPG are the relationship between an image compression standard and a format of pictures compressed using this standard;

If JPEG refers to is the suffix name of a picture file, and the relationship between JPEG and JPG is two different formats of pictures compressed using the JPEG standard.

jpg/jpeg is a 24-bit image file format and a platform-independent high-efficiency compression format. This file format is the product of the JPEG (Joint Photographic Expert Group) standard. The standard is jointly developed by ISO and CCI TT (Consultative Committee on International Telegraph and Telephone). It is a compression standard for continuous tone still images. Its original purpose is to use 64Kbps communication lines to transmit 720×576 resolution compressed images. By losing very little resolution, the storage required for the image can be reduced to 10% of its original size. Due to its high compression efficiency and standardization requirements, it has been widely used in the transmission of color faxes, still images, conference calls, printing and news pictures. However, those deleted data cannot be restored during decompression, so *.jpg/*.jpeg files are not suitable for enlarged viewing, and the quality will be affected when output as printed matter. However, ordinary users do not need to worry, because the compression algorithm of *.jpg/*.jpeg is very advanced, and it does not have a great impact on the loss of graphics and images. A 16M (24-bit) *.jpg/*.jpeg image looks like Not as big as the photo The difference is even indistinguishable to non-professionals. For the same picture, files stored in *.jpg/*.jpeg format are 1/10 to 1/20 of other types of graphic files. Under normal circumstances, *.jpg/*.jpeg files are only tens of KB, and the number of colors can reach up to 24 bits, so it is widely used on the Internet to save valuable network transmission resources. Similarly, in order to store more graphic images on a disc, CD publishers are also willing to use the jpg/jpeg format.

The difference between the two

The file format of JPEG generally has two file extensions: .jpg and .jpeg. The essence of these two extensions is the same. We can rename the *.jpg file to *.jpeg without any impact on the file itself. Strictly speaking, the file extension of JPEG should be .jpeg, but due to the 8.3 file name naming principle in the DOS era, PCs used the .jpg extension. Since Mac did not limit the length of the extension, so on Apple computers at that time All use the .jpeg suffix. Although Windows can now support extensions of any length, everyone is already used to the name .jpg, so there is no forced correction. This situation is similar to the difference between .htm and .html.

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