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Joint Picture Expert Group Resources

1. Introduction
2. Further Infos
3. Quality

Joint Picture Expert Group (JPEG) is a compression method which mainly is known as lossy compression with variable compression ratio, from 1:1 upto 40:1, and it mainly used form real-world picture and photos. It is not suitable to compress high contrast pictures such as bi-color pictures such as black/white GIFs.

LIBJPEG

This is the best library we came accross so far: LIBJPEG Documentation Documentation on using the library Independent JPEG Group Download the library

JPEG Lab 2. Further Infos

JPEG.Org: Links More infos	RTJPEG real-time JPEG library	MJPEG Toolset (Linux) Toolset to de/encode MJPEG
Linux Motion Video Card (MJPEG) capture board for full-rate MJPEG

JPEG Lab 3. Quality

Original (GIF, 150x150, 256 colors)

JPEG is most useful for photography with moderate contrast, for b/w clipart with high contrast it's not very suitable. Here a serie of a b/w clipart with rather high contrast ('A' is rendered antialiased though): an interesting area is cropped and scaled 4x:

JPEG 5% (4x)	JPEG 15% (4x)	JPEG 35% (4x)
JPEG 55% (4x)	JPEG 75% (4x)	JPEG 85% (4x)
JPEG 95% (4x)

                                                                                                                                   

GIF Lab

The GIMP