JPEG（联合图像专家组）
JPEG 是最广泛使用的照片和复杂图像格式。它采用有损压缩来实现较小的文件大小，同时保持可接受的视觉质量。JPEG 支持 24 位色彩（1670 万色），并被所有浏览器和设备普遍支持。
MIME 类型
image/jpeg
类型
二进制
压缩
有损
优点
- + Excellent compression for photographs
- + Universal browser and device support
- + Adjustable quality/size trade-off
- + Small file sizes for web delivery
缺点
- − Lossy compression degrades quality on re-saves
- − No transparency support
- − Not suitable for text, line art, or sharp edges
何时使用 .JPG
适用于照片、带有渐变的复杂图像，以及文件大小比像素级精确度更重要的任何场景。
技术细节
JPEG 采用基于离散余弦变换（DCT）的压缩技术。质量可在 1-100 之间调节，数值越高，保留的细节越多，但文件也越大。
历史
JPEG 由联合图像专家组开发，于 1992 年发布为 ISO 10918-1 标准。到 1990 年代中期，它已成为网络上的主流照片格式。
从 .JPG 转换
转换为 .JPG
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