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Sometimes i work with JPEG files for my web designs. There are occasions where the PNG format is not suitable..

There are several optimization techniques for the PNG format, but I noticed that for the JPEG format, the possibilities are limited, especially if you work on a Mac.

Probably the most elegant solution so far is the selective compression that allows you to precisely control the compression in specific areas of the images. If you combine then the image with JpegOptim and jpegtran from libjpeg (or use imageOptim) you can reduce even more the filesize.

I am still not satisfied by this options. I don't want to buy a license for fireworks only because of the selective jpeg, and I wonder if there's some other image optimization software out there that offers similar features..

On windows you have Jpeg Optimizer..

Is there any tool that you use for your workflows that you can suggest me?

Thank you

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    What is it you are trying to accomplish? If JPG compression is such an issues, then maybe you shouldn't be working with JPGs. The type of compression a JPG uses has never been an issue for me, but rather finding that balance between size and image quality using the defaults afforded to me by Photoshop. Done and done. Commented Aug 26, 2011 at 14:40
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    I am interested to know the reason why the OP finds it necessary to finely tune the compression in this manner. The only scenario I can conceive of right now involves a PBKb&C, but I am willing to be taught.
    – horatio
    Commented Aug 26, 2011 at 16:25

5 Answers 5

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  • MozJPEG is a modernized JPEG encoder, probably the best one you can find. I've made a basic web interface for it.

  • Guetzli specializes in producing high-quality files with nearly imperceptible distortions. It's very, very slow though.

  • JPEGmini is pretty good at recompressing JPEGs to the lowest still-good quality.

  • Adept and imgmin try to automatically adjust quality (avoiding unnecessarily-high quality saves a lot).

The last two are best combined with lossless ImageOptim (includes MozJPEG/jpegrescan) for the most efficient JPEG compression I'm aware of.

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  • With JPEGmini you have to do 2 lossy compressions instead of 1. :(
    – sam
    Commented Jul 19, 2014 at 1:09
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Ten years ago, this would have been a great question. But in 2011, unless you are sure that a high percentage of site visitors will be on dial-up or similar low-bandwidth connections, the effort put into selective compression doesn't produce enough value to be worth it. The differences in quality and file size are so minimal, and broadband connections so ubiquitous, that you end up saving no more than a few milliseconds in page load times.

Even mobile devices, constrained for the moment by 3G speeds in most places, will not benefit significantly from selective compression.

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    as of 2013 I don't think this is true anymore, at least for mobile - a lot of these 3G connections are not so fast. Also the amount of images used and the increase in device screen resolution calls for more optimal image compressions.
    – Luciano
    Commented Dec 12, 2013 at 16:11
  • This is like someone from Tokyo wondering what's the point of serving webms below 4K anymore. I mean, sure, if you're in LA, no kidding, I would expect 3G/4G to work perfectly. Commented Mar 22, 2016 at 10:56
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Lately I've been using ImageOptim and ImageAlpha with very good results.

ImageOptim is very good at optimizing and compressing GIF/JPEG/PNG and I'm using ImageAlpha to convert most of my images to PNG with good results: most of the times I get PNG files (full color) that are smaller than GIFs (50-60%), with very little quality loss. It even has an option for making "IE6-friendly" Alpha transparency (although I didn't test it).

Maybe not in 2011, but now PNG's are a good option, specially at such small sizes.

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I've been looking into this lately and running my own tests using many different tools and techniques.

I've found that for JPEG images, combining JPEGmini and ImageOptim (in that order) works best. They each do different things to reduce the image size.

For PNGs, I like ImageAlpha followed again by ImageOptim.

I don't plan to publish my benchmarks but they very closely mirror those published by Jamie Mason.

Jamie Mason also created an awesome command line tool for using these three image optimizers if you need a really deep level of control. Otherwise they all come with GUIs onto which you can drag-and-drop your images.

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i have done compression of images on many websites like compressnow.com, tinypng.com, but the compressed images is not equal to the original image in quality wise. it is not loss less compression. I then tried http://CompressPic.com, it actually solved my problem, that is why i recommend it to all here.

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  • Hello Sara, welcome to GDSE. Thanks for your answer! Could you elaborate a bit? For example, what type of software is it, how does it work, what benefits does it hold over other (similar) software or services, ...
    – PieBie
    Commented Sep 3, 2015 at 13:50

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