如何使用渐进式jpegs magento

I have to problem with Magento. I am testing speed of your site on http://www.webpagetest.org/ and result is "Use Progressive JPEGs: 0/100"

How to increase the point of using progressive JPEGs? I've read the guide here but it's not successfully. My magento version is 1.9.0.1 link

For Centos,

1. Go to terminal
2. yum install jpegoptim
3. Go to the folder containing images, which you want to optimize and run following command.
4. find . -iregex ".*.jpe?g" -exec jpegoptim --max=80 --strip-all --all-progressive {} \;

For Ubuntu,

1. Go to terminal
2. sudo apt-get install jpegoptim
3. Go to the folder containing images, which you want to optimize and run following command.
4. find . -iregex ".*.jpe?g" -exec jpegoptim --max=80 --strip-all --all-progressive {} \;

for more details please refer below links,

https://www.webmaster.net/tutorials/install-jpegoptim-in-ubuntu-or-centos-compress-your-images-losslessly-to-optimize-google-pagespeed-score.html