AgentZ - World Wide Agents
Effects of Compression Ratio on Image Quality
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As you scroll through these images it will become clear that there is a trade-off. The larger your images, the clearer they are with no perceptible distortion. As size drops ( higher compression ratios) your size (hence load time) decrease rapidly. What you will typically find is that compression ratios of 10:1 or less will offer the best overall trade-off between image quality and load time. In my table at the bottom you can readily see the effect on file size and load time. This is from the same target image in the previous examples.  
   Blow up of target image saved in JPG format with minimum compression 10:1 compression 15:1 compression 20:1 compression 25:1 compression 30:1 compression
File Size 28K 13K 9K 6K 5K 4K
Load Time (in seconds) 8 4 3 2 2 1
Compression Ratios1:110:1 15:1 20:1 25:1 30:1
In the table above, all load times are for a 28.8K modem download speed. To calculate for a 56K modem divide by two. These are optimum times and do not take into account server lag and traffic delays.


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