What is jpeg compression object

What is jpeg compression object?

JPEG is an international standard for digital signal compression. The object is a static image.

JPEG is the abbreviation of Joint Photographic Experts Group (Joint Photographic Experts Group). The file suffix is ​​".jpg" or ".jpeg" and is the most commonly used image file format.

It is a lossy compression format that can compress static images into a small storage space. Repeated or unimportant data in the image will be lost, so it is easy to cause damage to the image data. In particular, using an excessively high compression ratio will significantly reduce the quality of the image restored after final decompression. If you pursue high-quality images, it is not advisable to use an excessively high compression ratio.

Extended information

JPEG compression standard:

JPEG is developed by the International Standards Organization (ISO) and the Consultative Committee for International Telephone and Telegraph (CCITT) for static The first international digital image compression standard created by the image, it is also the most widely used image compression standard that has been used to this day. Because JPEG can provide lossy compression, the compression ratio can reach a level that other traditional compression algorithms cannot match.

JPEG compression mode:

1. Sequential Encoding

Process the image sequentially from left to right and top to bottom at a time.

2. Progressive Encoding

When the image transmission takes a long time, the image can be processed in batches to transmit the image from blur to clear (the effect is similar GIF transmission over the Internet).

3. Lossless Encoding

4. Hierarchical Encoding

The image is compressed at several resolutions. The purpose is to Allows images with high resolution to be displayed on lower resolution devices.

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