Opera Talks: Opera Mini and Data Compression

February 9, 2012 · by Anna Rohleder

One of the things that makes Opera Mini the world's most popular mobile browser is its ability to compress data. Of course, you know that it saves you time and money - but do you know how data compression really works?

As much as we'd like to think it's all done with a wave of a magic software wand, it turns out that data compression is not one single action so much as a set of processes that preps content from the web and makes it faster and easier to consume on your phone.

Martin Nilsson, Solution Architect for Opera Mini, explains how Opera Mini is able to serve up so much internet tastiness.

Martin, when did the idea for data compression in Opera Mini first come about?

The first project Opera worked on that involved compression of mobile data was the Opera Mobile Accelerator (editorial note: launched in 2004, this was a subscription-based service that cost EUR 12 for 3 months of service!). That project was discontinued and we started working on Opera Mini instead. The idea with Opera Mini was to make a browser for (at the time) browserless phones.

How does Opera Mini work today?

Unlike ordinary web browsers, Opera Mini fetches all content through a proxy server that reformats web pages into a format more suitable for small screens. A page is compressed, then delivered to the phone in a markup language called OBML (Opera Binary Markup Language). This compression process makes transfer time about two to three times faster and the pre-processing also increases compatibility with web pages not designed for mobile phones.

What do the servers do in terms of reformatting?

Mobile devices differ in many ways to desktop devices. Given the smaller screen size, different text handling may be used to improve readability. Also between mobile devices there are those with only numeric keyboard, those with QWERTY keyboard, with D-pad, stylus, touch etc. Many things that work on desktop don't work on mobile, especially when there is no mouse pointer to scroll frames or do mouseover actions. To solve these many small usability issues, tweaks need to be made.

What happens when the data gets compressed?

First of all, and this is very important, data compression doesn't actually help very much in terms of speed. What matters is the latency, the time from the user action until the first response is seen. Some of the primary methods for reducing latency include:

Our own client-server protocol that keeps a connection established for sending requests. There is a 20-30% end user benefit in terms of latency.
Since we use a single-request - single-response protocol we minimize the usage of the high latency radio network and instead fetch all the inlines, stylesheets etc. from our fast servers.
We connect directly to some content partners like Facebook and Google, and even have other companies' web servers in our server rooms so that the latency from our transcoders relative to the volume of content is as small as possible.

There are also several different types of compression and data reduction used in Opera Mini.

The servers keep information about the clients, so this information only needs to be sent from the client to the server once, instead of in every request.
Cookies are managed entirely on the server side, so that data never have to go back and forth at all.
Images are scaled to better fit the display size of the device to make them as size efficient as possible while making the resulting web page as good looking as the end user quality settings permit.

Finally, the resulting data is compressed in different ways. Normally we send text first, followed by links, essential layout elements and finally all graphics. We focus also on sending data where the user will start reading before other parts of the page.

Given that all the data has to pass through Opera's servers, what about security issues?

Opera Mini is like a desktop computer. The browser sits in the computer while the user looks at the screen. In Opera Mini the browser sits on our servers while the user is looking at the page in their handset. We know that the success of Opera Mini depends on us being able to run the servers securely. So far we have not had any incidents.

Are Opera Mini servers all in Norway?

There are some in Norway, but we have servers at multiple locations, where it makes sense from an economic and performance perspective. One example is our Iceland data center, which sits right between US and Europe, and benefits from geothermal energy.

Readers' comments 60

Left under the original article, as archived.

TamilThursday, February 9, 2012 3:47:37 PM
d4rkn1ghtThursday, February 9, 2012 4:08:35 PM

Sleeping Cat!
SamThursday, February 9, 2012 4:56:32 PM
This is great. Though, in my opinion, Opera needs to find a way to compress video. If they do this, get ready for a massive amount of new users.
Charles SchlossThursday, February 9, 2012 5:10:39 PM
NimeshThursday, February 9, 2012 6:04:12 PM
Nice article.

What information is captured from users side?
And what kinds of testing has been done to ensure security of users data?
praetor87Thursday, February 9, 2012 6:51:43 PM
It's a Motorola L7!
Tom RondelloThursday, February 9, 2012 7:44:16 PM
Thank you for a truly informative article. I, for one, greatly appreciate it.
Some things are way more difficult than counting jewels.

Sincerely,
One little kid at
ChirpieThursday, February 9, 2012 8:52:58 PM
Originally posted by HuRRaCaNe:

This is great. Though, in my opinion, Opera needs to find a way to compress video. If they do this, get ready for a massive amount of new users.
That didn't work for Bolt or Skyfire. Both of them tried video compression. Bolt is now gone, and Skyfire charges you if you want to view videos.

It's just too expensive to compress videos.
[email protected]Thursday, February 9, 2012 9:52:59 PM
I luv u all
OuttaControlCROFriday, February 10, 2012 12:59:55 AM
mine is 92% 795,4 MB to 69,1
ZuritaMardukFriday, February 10, 2012 1:06:19 AM
I appreciate this technology and want it for my Nokia N9. Please.
Phillip Robert O'ConnerFriday, February 10, 2012 1:13:49 AM
I Got On My iPad And I Think My Is 76-90% Data Compress.Working How To Take A Picture Of Much Is Really On It.
PettyngashFriday, February 10, 2012 1:59:02 AM
As a community is it possible to add voip feature or video call to opera users? I mean anyone with opera browser or opera mini can call each other freely.
SamFriday, February 10, 2012 2:14:28 AM
Originally posted by Chirpie:

Originally posted by HuRRaCaNe:
This is great. Though, in my opinion, Opera needs to find a way to compress video. If they do this, get ready for a massive amount of new users.
That didn't work for Bolt or Skyfire. Both of them tried video compression. Bolt is now gone, and Skyfire charges you if you want to view videos.

It's just too expensive to compress videos.
That's why they need to find a way to make this technically and monetarily possible. They'll be the only one to reliably provide the service. Though it's most likely not practical at all to do this.
Alf RedFriday, February 10, 2012 4:37:50 AM
upgrade your browser so tat one can upload a twitter profile picture. currently its impossible.
akamaru9590Friday, February 10, 2012 5:54:32 AM
I have a problem with my opera mini 6.5. Everytime i try to download videos it always says ''downloading failed check network settings''. But i can get music tracks/photos etc. Can someone please help me up?
Daniel BandaFriday, February 10, 2012 6:51:55 AM
Thanks! I was wondering how the amazing Opera Mini works. Now i know how it works.
Sami SerolaFriday, February 10, 2012 7:47:23 AM
I Opera Mini 88% out of 4GB at the moment
Sami SerolaFriday, February 10, 2012 7:51:48 AM
Originally posted by akamaru9590:

I have a problem with my opera mini 6.5. Everytime i try to download videos it always says ''downloading failed check network settings''. But i can get music tracks/photos etc. Can someone please help me up?

Go to Opera Mini forum to ask it again and mention what device you have.
http://my.opera.com/community/forums/forum.dml?id=111
Although, I think the problem is with your phone's download manager, not with Opera Mini.
Aleksander AasFriday, February 10, 2012 8:27:14 AM
Thank you for the great feedback on this article. We'll try to get more stuff like this out in the future. Speaking of: What would you like to know more about?
orphinsitFriday, February 10, 2012 9:33:24 AM
its good to read your post thanks for sharing nice info...........
HayathFriday, February 10, 2012 11:16:20 AM
cool
nimbuzz loginFriday, February 10, 2012 11:31:35 AM
nimbuzz:Operateam work very well
vas ilioFriday, February 10, 2012 2:48:51 PM
it is awesome
darlene costa barbosaFriday, February 10, 2012 6:22:51 PM
nossa o lucas nao mim ligou mais poxa:)
mostafaSunday, February 12, 2012 1:48:39 AM
j
NakTT De MaliziSunday, February 12, 2012 3:41:40 AM
Wish we could have option to use OBML on PC to safe bandwidth as Turbo is not as good as Opera Mini with OBML.
beckerSunday, February 12, 2012 7:13:13 AM
nice
SoumitraSunday, February 12, 2012 8:13:50 AM
darlene costa barbosaSunday, February 12, 2012 5:47:51 PM
so da doido na net kkkk
darlene costa barbosaSunday, February 12, 2012 5:48:58 PM
e verdade kkkkkk
Thomas o.AddySunday, February 12, 2012 7:55:45 PM
Opera no size
mostafaSunday, February 12, 2012 11:36:47 PM
j
The Lodge ShopMonday, February 13, 2012 5:25:20 PM
philaniWednesday, February 15, 2012 12:16:21 PM
That is my beautiful wife and son and i am very proud of both of them. I have just joined opera, so hi every one i hope we gonna have a nice place of sharing as friends.
edi temposWednesday, February 15, 2012 12:23:02 PM
nice
vidadebandidoThursday, February 16, 2012 1:45:22 PM
hola soy nuevo y no se sincronizar
Maria V. BrunoThursday, February 16, 2012 2:16:40 PM
You give us a nice browser, thanks.
I don't have flash in my phone, if I enter in YouTube on my phone, it's only to remember some name at that moment...
PRAMOD ROHILLAThursday, February 16, 2012 3:05:50 PM
when i start playing avideo from youtube then my phone say start strean how cn i start strean???
alvrtFriday, February 17, 2012 3:13:28 AM
i really tried to use Opera web browser in my iphone and in my macbook. but im very frustrated. thanks Opera for trying hard to keep me with you. but i dont care about data savings, i care about functionality. hope you can improve, i will check back in several months, like a did before but i see you made changes but still suks.
inknzvl
Joel Julian Salas LópezFriday, February 17, 2012 7:43:36 AM
Originally posted by inknzvl:

... but i dont care about data savings, ... still suks.
inknzvl

And who cares about you foul-mouthed troll? , anybody forces you to use Opera, you're free to give your being to Apple, here there is only place for constructive feedback no for impolite fanboys.
Joel Julian Salas LópezFriday, February 17, 2012 7:45:11 AM
Originally posted by Aleksander:

Thank you for the great feedback on this article. We'll try to get more stuff like this out in the future. Speaking of: What would you like to know more about?

Wold be great some articles of the next list:
- Web Standards and compatibility issues (by the great Chaals ).
- The blending edge of CSS in Opera (by the lord of the CSS Håkon Wium Lie)
- Opera's HTML5 implementation (by the charismatic Bruce Lawson)
- Security in Opera (in general, in addition to Opera Mini)
- Web GL, and Hardware acceleration in Opera.
- Opera's partnerships around the world.
- Opera environment and social commitment.
Well that are all my suggestions, hope this helps.
Joel Julian Salas LópezFriday, February 17, 2012 7:45:43 AM
Spanish translation published in Opera Español:
http://my.opera.com/espanol/blog/2012/02/17/opera-nos-cuenta-opera-mini-y-la-compresion-de-datos
Anna RohlederFriday, February 17, 2012 8:12:09 AM
Originally posted by jjsl6:

Spanish translation published in Opera Español:

http://my.opera.com/espanol/blog/2012/02/17/opera-nos-cuenta-opera-mini-y-la-compresion-de-datos
Gracias, Julian!
MD. KAMAL UDDIN HAWLADARFriday, February 17, 2012 7:19:01 PM
Moderator Note: Comment removed
MD. KAMAL UDDIN HAWLADARFriday, February 17, 2012 7:20:27 PM
It is very good news for us. I like it.
Derek KnoppSaturday, February 18, 2012 3:43:03 AM
Nice
mangwirothembaSaturday, February 18, 2012 5:00:55 PM
opera is doing fine for me keep it up
Tinashe MazhawidzaSunday, February 19, 2012 2:49:21 PM
I'm very much in love with opera,but i'm asking for this one thing: make it possible to copy and paste pictures using a mobile phone.
АлександрSunday, February 19, 2012 6:35:29 PM
что такое? непонятно..