汉英对照:
Chinese-English Translation:
JPEG（Joint Photographic Experts Group）是是面向连续色调静止图像的一种压缩标准。JPEG格式是最常用的图像文件格式，后缀名为.jpg或.jpeg。
JPEG (Joint Photographic Experts Group) is a compression standard for continuous tone still images. JPEG is the most commonly used image file format with a suffix of. JPG or. JPEG.
JPEG（Joint Photographic Experts Group）是 JPEG 标准的产物,该标准由国际标准化组织制订，是面向连续色调静止图像的一种压缩标准。JPEG 格式是最常用的图像文件格式，后缀名为.jpg 或.jpeg。
JPEG (Joint Photographic Experts Group) is the product of the JPEG standard, which is developed by the international organization for standardization and is a compression standard for continuous tone still images. JPEG is the most commonly used image file format with a suffix of. JPG or. JPEG.
JPEG（ Joint Photographic Experts Group）即联合图像专家组，是用于连续色调静态图像压缩的一种标准，文件后缀名为，jpg 或，jpeg，是最常用的图像文件格式。其主要是采用预测编码（DPCM）、离散余弦变换（DCT）以及熵编码的联合编码方式，以去除冗余的图像和彩色数据，属于有损压缩格式，它能够将图像压缩在很小的储存空间，一定程度上会造成图像数据的损伤。尤其是使用过高的压缩比例，将使最终解压缩后恢复的图像质量降低，如果追求高品质图像，则不宜采用过高的压缩比例。
JPEG (Joint Photographic Experts Group) is a standard for continuous tone still image compression. The file suffix is JPG or JPEG, which is the most commonly used image file format. DPCM, DCT and entropy coding are used to remove redundant image and color data. It belongs to lossy compression format. It can compress image in a small storage space, which will cause damage to image data to a certain extent. In particular, the use of high compression ratio will reduce the quality of the restored image after the final decompression. If the pursuit of high-quality image, it is not appropriate to use high compression ratio.
然而，JPEG 压缩技术十分先进，它可以用有损压缩方式去除冗余的图像数据，换句话说，就是可以用较少的磁盘空间得到较好的图像品质。而且 JPEG 是一种很灵活的格式，具有调节图像质量的功能，它允许用不同的压缩比例对文件进行压缩，支持多种压缩级别，压缩比率通常在 10；1 到 40；1，压缩比越大，图像品质就越低；相反地，压缩比越小，图像品质就越高。同一幅图像，用 JPEG 格式存储的文件是其他类型文件的 1/10~1/20，通常只有几十 KB，质量损失较小，基本无法看出。JPEG 格式压缩的主要是高频信息，对色彩的信息保留较好，适合应用于互联网；它可减少图像的传输时间，支持 24 位真彩色；也普遍应用于需要连续色调的图像中。
However, JPEG compression technology is very advanced, it can use lossy compression to remove redundant image data, in other words, it can use less disk space to get better image quality. And JPEG is a very flexible format, with the function of adjusting image quality. It allows to compress files with different compression ratios, supporting multiple compression levels. The compression ratio is usually 10; 1 to 40; 1. The larger the compression ratio, the lower the image quality; on the contrary, the smaller the compression ratio, the higher the image quality. For the same image, the file stored in JPEG format is 1 / 10 ~ 1 / 20 of other types of files, usually only tens of kilobytes, with little quality loss, which can hardly be seen. JPEG format compression is mainly high-frequency information, which has better retention of color information and is suitable for Internet application; it can reduce the transmission time of image and support 24 bit true color; it is also widely used in images requiring continuous tone.
JPEG 格式可分为标准 JPEG、渐进式 JPEG 及 JPEG2000 三种格式。
JPEG format can be divided into standard JPEG, progressive JPEG and JPEG 2000.
1. 标准 JPEG 格式；此类型在网页下载时只能由上而下依序显示图像，直到图像资料全部下载完毕，才能看到图像全貌。
1. Standard JPEG format; this type can only display images from top to bottom in order when downloading web pages, and can only see the full picture of the image until all image data are downloaded.
2. 渐进式 JPEG；此类型在网页下载时，先呈现出图像的粗略外观后，再慢慢地呈现出完整的内容，而且存成渐进式 JPG 格式的文档比存成标准 JPG 格式的文档要来得小，所以如果要在网页上使用图像，可以多用这种格式。
2. Progressive JPEG: when downloading a web page, this type first presents the rough appearance of the image, then slowly presents the complete content, and the document saved in progressive JPG format is smaller than that saved in standard JPG format, so if you want to use the image on the web page, you can use this format more.
3. JPEG2000；它是新一代的影像压缩法，压缩品质更高，并可改善在无线传输时，常因信号不稳造成马赛克现象及位置错乱的情况，改善传输的品质。
3. JPEG2000: it is a new generation of image compression method with higher compression quality. It can improve the mosaic phenomenon and position disorder caused by signal instability in wireless transmission, and improve the transmission quality.
