Serving scaled images.

I have regenrated tumbnails to see why still i am having problems. Even when i check html it seems everything ok. Btt gtmetrix give this errors.

The following images are resized in HTML or CSS. Serving scaled images could save 33.8KiB (17% reduction).

http://www.estambul.net/wp-content/uploads/2015/03/mezquita-azul-745×483.jpg is resized in HTML or CSS from 745×483 to 671×435. Serving a scaled image could save 8.9KiB (19% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/palacio-de-beylerbeyi-estambul-net-2-326×159.jpg is resized in HTML or CSS from 326×159 to 301×147. Serving a scaled image could save 3.5KiB (15% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/moneda-estambul-net-5-326×159.jpg is resized in HTML or CSS from 326×159 to 301×147. Serving a scaled image could save 3.4KiB (15% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/nargile-estambul-net-4-326×159.jpg is resized in HTML or CSS from 326×159 to 293×143. Serving a scaled image could save 3.1KiB (20% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/clima-estambul-net-5-326×159.jpg is resized in HTML or CSS from 326×159 to 301×147. Serving a scaled image could save 2.5KiB (15% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/mezquita-azul-326×159.jpg is resized in HTML or CSS from 326×159 to 301×147. Serving a scaled image could save 2.5KiB (15% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/cisterna-de-basilica-estambul-326×159.jpg is resized in HTML or CSS from 326×159 to 301×147. Serving a scaled image could save 2.1KiB (15% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/paseo-por-el-bosforo-estambul-net-326×406.jpg is resized in HTML or CSS from 326×406 to 293×365. Serving a scaled image could save 2.0KiB (20% reduction).
http://www.estambul.net/wp-content/uploads/2010/03/mapa-de-estambul-net-2-326×235.jpg is resized in HTML or CSS from 326×235 to 293×211. Serving a scaled image could save 1.6KiB (20% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/paseo-por-el-bosforo-estambul-net-326×159.jpg is resized in HTML or CSS from 326×159 to 293×143. Serving a scaled image could save 1.1KiB (20% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/bano-turco-estambul-net-326×235.jpg is resized in HTML or CSS from 326×235 to 301×217. Serving a scaled image could save 1.1KiB (15% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/bano-turco-estambul-net-326×159.jpg is resized in HTML or CSS from 326×159 to 293×143. Serving a scaled image could save 1.1KiB (20% reduction).
http://www.estambul.net/wp-content/uploads/2015/03/preguntas-freceuntes-estambul-net-2-326×159.jpg is resized in HTML or CSS from 326×159 to 293×143. Serving a scaled image could save 710B (20% reduction).

I am not using w3 total cache.

BUt on the html i do nto see anything wrong. even it says scaled but html or css doesnt show any change.

IF there is any problem with this tumbs how we can solve.

Well on mobile devices “responsive” images have to be resized as there is now way of knowing what the actual thumbnail size might be if you have 3 images side by side in a grid; well the width of that grid might change depending on the device.

You *could* add more image sizes to your functions file to build those additional sizes; keeping in mind you might end up with 20 images per raw image (!). If you have the storage space or using CDN, might be worth it.

Or, consider using something like mod_Pagespeed with your hosting provider — which is what we do — if 50 people request a new image size, scaled from larger image — it MAKES ONE and caches it. Wicked cool.

Or, ignore that suggestion and go run the official Google PageSpeed Insights check and if they don’t bug you about those scaled images, just ignore it.

I have seen somewhere thatw e can make changes on functions and module code to change the dimensions as we want.

When i check functions i didnt see anything on functions on that.

We need to make changes on which files?

Thanks