New: Caesium Portable 1.7.0 (image optimizer and converter) Released

Ken Herbert's picture
Submitted by Ken Herbert on October 10, 2014 - 11:53pm

logoCaesium Portable 1.7.0 has been released. Caesium lets you convert and optimize multiple image formats. It's packaged in Format so it can easily integrate with the Platform. And it's open source and completely free.

Update automatically or install from the portable app store in the Platform.



Caesium allows you to compress images and convert between multiple formats to save space on your hard drive, send images faster, and decrease website bandwidth.

Learn more about the Caesium... Installer / Format

Caesium Portable is packaged in a Installer so it will automatically detect an existing installation when your drive is plugged in. It supports upgrades by installing right over an existing copy, preserving all settings. And it's in Format, so it automatically works with the Platform including the Menu and Backup Utility.


Caesium Portable is available for immediate download from the Caesium Portable homepage. Get it today!

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John T. Haller's picture

Thanks for your work on this Ken! I updated it to the latest version and added in Qt key handling for the official release.

Sometimes, the impossible can become possible, if you're awesome!

Ken Herbert's picture

Thank you for the release, John.

I must have missed those registry keys when I last updated it, because I ended up with the assumption that Qt5 no longer wrote to the registry, so thanks for picking up on that.

At the software's site there is identical text under the six "Features you need" section to which a "Take tour" link points.

I visited it to know about something about the methods allowing more than 90% compression from the original format.
I would have been curious how is it possible to compress a 2 megabyte jpeg to 200 kilobyte without quality loss. I still do not have the slightest idea of it.

Forgive my undereducation if this piece of software is well known among millions of people, and in their context the statement is right.

John T. Haller's picture

Any optimization product can achieve 90% compression by converting a specific BMP to a PNG or JPG without any noticeable loss in quality. But that's more marketing-speak, which is why it's not included in the description here.

Sometimes, the impossible can become possible, if you're awesome!

Sorry, description says it leaves the format. BMP to BMP. JPG to JPG. 90 percent compression -- but no mention of picture size!
It sounds, that you get a 4000x3000 pixel image with 10% file size.
The description is false.
I would take into consideration to omit Caesium from Portableapps, or correct the description.

John T. Haller's picture

And, I say yet again, "read the description here". As in here, on this site. It's accurate.

Sometimes, the impossible can become possible, if you're awesome!

So, guys yes, Caesium is an image converter.
It converts an image from 4000x3000 pixels to 1000x750 pixels, to 8% of original size without quality loss.
As the godzillion picture editors out there.
Too much words I wasted for it.
You don't.

John T. Haller's picture

If you read my comment above, I already explained it. And why we don't use that "90%" language. I can take a 700KB PNG and save it as a 70KB 50% quality optimized JPG in Photoshop without any really noticeable loss in quality. But EVERY FILE IS DIFFERENT. So, using that marketing speak of 90% is disingenuous. What this app does allow you to do is batch convert files from one format to another, compress them to small JPGs (file size not image size), etc. This is useful in lots of ways and we use similar tools to get the images you see on as small as possible. None of our images compress 90% which is, again, why we don't use that language in the description of the app.

Sometimes, the impossible can become possible, if you're awesome!

I don't exactly understand your problem here. There is no magic app out there that miraculously can do, what is not possible.
BMP is either uncompressed or uses the weak RLE compression. You can significantly reduce file size only with lossy compression (jpg/png f.i.). To further reduce file size, the compression rate has to be increased. If a file already uses a high compression rate the gain will be small.
There are differences how good algorithms can compress images without making artifacts visually obvious. And its all weighting size vs. purpose - same as mp3 compression for music where vbr at ca. 200kbs normally is considered lossy but transparent.
So, Caesium does no more than that. It recompresses images with higher compression to reduce file size, or it reduces it's images size if you particularly wish to do so. Up to 90% is possible depending on the file and the tolerated losses. I tried it on a rather complex photo and the results where more or less usable at a file size reduction from 1.6 Mb to 470Kb.

It's up to you to take their promotional talk (or what these place holders on their hp are) for real or use your brain. I don't like such catchwords either and there are way better apps out there with higher quality (I use xat image optimizer), but that's not the point.

solanus's picture

Yes, the website is rather repetitive and uninformative. I suspect that they are better at writing code than at writing descriptive copy :). Perhaps the site is a work in progress.

As John did not repeat the hyperbolic claims of the original programmer, and only claims that it is an image converter, it seems that your best way to get a satisfactory answer is to contact the original programmer and ask for clarity, as well as suggesting that they devote more attention to detail on their site. There is a handy-dandy form at the bottom of the Caesium website just for that.
Basically, yes, it is just another image batch converter, like many out there - I personally use RIOT with good results. This one happens to be open source, which is one of the reasons it is included here. As a PortableApp, you can install it and experiment with it - if you don't like it, uninstall it, no harm, no foul.

As for whether it belongs on PortableApps - I don't see why not.

I made this half-pony, half-monkey monster to please you.

I came across this website featuring my app a bit late, but I hope you would still appreciate the effort.

Maybe my marketing office went too far and you got stuck in their "promotional talk" - I'm the marketing office myself, by the way - and you didn't find it very informative. Yeah, I can second that.

But, as someone already said, there're no miracles involved. The app can compress up to 90% (well, in some specific scenarios you can go upper) without VISIBLE quality loss. JPEGs are lossy and you will always get a different image by compressing it, but your eyes don't always think the same way. Depending on a huge number of factors, the results may satisfy you or not, and this is something you may want tell to me with a raging email.
So, TL;DR, 90% is an achievable goal, in some cases. In most of them you will fall between the 60-70%.
Just as a note, lossless JPEG optimization is a thing, that can reduce your pictures up to 18-20% keeping the same, identical, picture. "Up to", the average is 10%. I'm working on that but I'm pretty sure I can't advertise myself.

Anyway, I always try to improve my little creatures and I will keep in mind this discussion when talking to my marketing office again. And, of course, I will talk to the lead programmer that is trying to update Caesium and make it better (ye, I'm the lead programmer too, my team is very small).

If you want any further info, just contact me, my email is pretty easy to find. I will be happy to answer any question.

Have a nice day using your favorite image compression software!