What format is jpg?

JPG is a JPEG format file. JPEG format is the most commonly used image file format, with the suffix ".jpg" or ".jpeg". JPG format standards are divided into three types: JPEG, progressive JPEG, and JPEG2000. It is a standard generally used for continuous-tone static image compression. It is lossy compression, which compresses data images in a small storage space while causing loss of image data. Damage, if the user has higher requirements for image quality, it is recommended to abandon this image file format, especially for some high-definition pictures.

# Operating system for this tutorial: Windows 10 system, Dell G3 computer.

JPG generally refers to JPEG (Joint Photographic Experts Group), which is an image file format, and the extension is generally .jpg/.jpeg. Common image file formats include PNG, BMP, GIF, TIF, EPS, SVG, etc.

The format standards of JPG are divided into three types: JPEG, progressive JPEG, and JPEG2000. A standard commonly used for continuous-tone static image compression is lossy compression, which compresses data images into a small storage space while causing damage to the image data. If the user has higher requirements for image quality, it is recommended to abandon this image file format, especially for some high-definition pictures.

The advantages and disadvantages of JPG are briefly listed below:

Advantages

1. High compression rate and fast download speed ;

2. Small file size and fast transmission speed;

3. Strong format versatility and good device compatibility.

Disadvantages

1. Lossy compression reduces image quality;

2. JPG photos have been processed, making post-processing difficult;

3. Not all web pages support inserting photos in JPG format.

Supplement

According to the Open System Interconnect Reference Model (Open System Interconnect, OSI) jointly developed by the International Organization for Standardization (ISO) and CCITT, it can be seen from It is divided into 7 layers from bottom to top: physical layer, data link layer, network layer, transport layer, session layer, presentation layer and application layer. JPG is located in the presentation layer, which acts as the "translator" between applications and the network. In the presentation layer, data is formatted in a way that the network can understand, data conversion, text compression, decryption and encryption, etc. Common protocols at this layer include: JPEG, ASCII, GIF, DES, MPEG, etc.

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