jpeg loss and perceptual quality -?

Started by vlya...@gmail.com April 2, 2012
Was there any research on correlation between jpeg encoding loss and perceptual quality of resulting image?
For example, ImageMagic "convert" can recompress existing image with 25-50% loss of quality with no visible degradation of image ( resulting in smaller image).
So, how much loss can be introduced in JPEG compression without perceived loss of quality and how much storage space can be saved from it?
Can someone point me to white papars or books that research those questions?