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Crash Course - Image Optimization

I've been reading a lot about Image Optimization for the web over the past couple of weeks. This is something I can no longer ignore since wait times (while images are loading) lead to frustrated readers. I've improved some of my old Image Magick scripts (Perl). mogrify -geometry $size convert -density 72x72 -filter lanczos -compress JPEG -quality 80 $fntn
where $size is a x value and $fntn is the filename variable (both are passed in as arguments). The density is essentially the dpi. The lanczos filter is an effective compression algorithm. Perhaps the most interesting fact is that Image Quality is NOT a percentage. In fact it is somewhat meaningless in that it varies from program to program. It is a good idea to test the level of quality in an image to find the maximum quality reduction (which is positively correlated to byte size reduction) that doesn't visibly degrade the appearance of the image. That isn't as easy to automate. ARTICLES: