JPEG Compreression Induced artifacts

These pages demonstrates JPEG artifacts as seen (discerned) at various quality factors. The original image as a 231kB BMP is here.

Slight JPEG compression is sometimes tolerable for publishing purposes but for image editing and manipulation the JPEG is a totally unacceptable image format. See the 2X enlarged or the 4X enlarged versions of this page, you will notice large degradation between the original and the best JPEG quality that has only 3.12 compression in file size.

Images were JPEG compressed using Photoshop that provides quality levels 0...12.

Please note that there are 14 image on this page and some of them are rather large in file-size . The Option buttons do not change the images until the page has completely loaded. There after the Option buttons do switch the images in a blink.

Non-lossy PNG Quality 12 /74kB / 3.12:1 Quality 11 /51kB / 4.53:1 Quality 10 /38kB / 6.08:1 Quality 9 /31kB / 7.45:1 Quality 8 /26kB / 8.88:1 Quality 7 /22kB / 10.5:1 Quality 6 /21kB / 11:1 Quality 5 /18kB / 12.83:1 Quality 4 /17kB / 13.59:1 Quality 3 /15kB / 15.4:1 Quality 2 /13kB / 17.77:1 Quality 1 /11kB / 21:1 Quality 0 /11kB / 21:1

Images are already in the cache of your browers so the below are fast:

this page with the images zoomed by 200%

this page with the images zoomed by 400%

Accurate Image Manipulation for Desktop Publishing 

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