ImageGear .NET - Updated
Progressive JPEG Compression
User Guide > File Formats and Compressions > Compressions > JPEG Compressions > Progressive JPEG Compression

Full Name Progressive JPEG Compression
Compression ID ImGearCompressions.JPEG = 6
ImageGear Assembly ImageGear24.Core Assembly
Bit Depth Gray level: 8, 16 bpp; RGB: 24, 36 bpp; CMYK: 32 bpp; RGB+Alpha: 32 bpp
File Formats JPEG
IG Platforms Support WIN32, WIN64, Unix, Unix64, .NET, .NET64, MAC


Progressive JPEG is considered an extension to the JPEG standard. It produces the same kind of lossy compression as normal JPEG compression (see above), except that it saves multiple copies of the same image using different levels of quality. There is no hard limit on the number of "scans" that may be stored.

When a Progressive JPEG-compressed image is decompressed, the filter decompresses the lowest quality image first. This can be helpful for quickly displaying a version of the image that you are loading. The benefit of this compression is the fast display of an image that is recognizable. The downside is that a JPEG decompression is performed more than once.