Difference between revisions of "Batch jpeg Image Optimization"

Revision as of 20:18, 11 March 2014

How to compress a jpg image on Centos

The other day I was running a webpagetest on a clients site and the results were telling me to Compress Images

Now there was close to 200 images that needed to be compressed and optimized. That is when I found jpegoptim

You can learn more about jpegoptim, by reading the man page.

Optimize a Single Image

If you are looking to optimize a single image, you would just type

jpegoptim image.jpg

Sample output

image.jpg 710x275 24bit N JFIF  [OK] 143161 --> 136256 bytes (4.82%), optimized.

Optimize all JPEG images

You can use the find command to locate all *.jpg images under your current directory by using the following

for x in $(find $PWD -iname "*.jpg"); do jpegoptim $x; done

By default it will optimize all images in their current locations.

Optimize all JPEG images and convert to Progressive

You will also get a boost in load speeds by converting all images to use progressive, meaning that the entire images does not need to load before going to next request.

 for x in $(find $PWD -iname "*.jpg"); do jpegoptim --all-progressive $x; done

Now rerun your webpagetest and see the differences

Here are our results - http://www.webpagetest.org/result/140311_HN_10Z0/