What format is jpg?

jpg is an image format file, and jpg generally refers to the JPEG format. The full English name of JPEG is Joint Photographic Experts Group, which is the product of the JPEG standard. This standard is formulated by the International Organization for Standardization ISO and is for A compression standard for continuous-tone still images.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

JPEG (full name is Joint Photographic Experts Group) is a common image format. The file extension is ".jpg" or ".jpeg". It was developed by the Joint Photographic Experts Group and named "ISO 10918-1", JPEG is just a common name.

jpeg is developed by a software development association. It is a lossy compression format that can compress images into a small storage space. Repeated or unimportant data in the image will be lost, so it is easy to cause the image to be damaged. Data damage. In particular, using too high a compression ratio will significantly reduce the quality of the image recovered after final decompression. In pursuit of high-quality images, it is not advisable to use too high a compression ratio.

At the same time, JPEG is also a very flexible format, with the function of adjusting image quality, allowing different compression ratios to be used to compress this kind of file. For example, we can compress a 1.37MB BMP bitmap file to a maximum of 20.3 KB.

The compression technology of the JPEG file extension is very advanced. It removes redundant images and color data, obtains extremely high compression rates, and displays very rich and vivid images. In other words, That is, you can get better image quality with the least disk space.

Extended information:

The compression modes of JPEG are as follows:

1. Sequential Encoding: once Process the images sequentially from left to right and top to bottom.

2. Progressive Encoding: When the image transmission takes a long time, the image can be processed several times to transmit the image from blur to clear (the effect is similar to GIF on the Internet) transmission).

3. Lossless Encoding

4. Hierarchical Encoding: Images are compressed at several resolutions, the purpose of which is to achieve high resolution The images may also be displayed on lower resolution devices.

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