Picture Messages Defy Logic!

[slikmik]

Ok i find this strange anybody have any ideas? :confused:

Here we go:

An SMS message = 160 characters

Picture Message diameters = 71 x 27

Area of Picture Message = (71 x 27) = 1917

So 1917 total pixels and thus if the pixels are signified as either 0 or 1 in an sms to indicate dark or blank pixel then we divide this number by 160...

1917 / 160 = 11.98125

Ok so thats 12 SMS messages!

So why when you send a picture message does it send THREE (3) SMS MESSAGES??

Plus it lets you have 121 characters so this added to 1917 is 2038 which is 12.7375 SMS Messages thus obviously 13 Messages!

An operator logo you send as ONE SMS MESSAGE:

But...
Area of Operator Logo = (71 x 13) = 923 Pixels
So if sent in bits of 0 and 1's in an SMS that would be 5.76875 SMS Messages - 6 Messages rounded up so how come it can send it in one??

It defies all logic unless it sends LONGER SMS MESSAGES or uses some kind of wacky compression ratios

Well im boggled so anyone out there with any clue please explain

Cheers Guys

Mike -=NokiaFreeRulez=- :)

[KnOeFz]

I don't know how to calculate it exactly but what seems wrong in your calculation is 1917/160...

each of the 160 characters needs more that just 1 bit to be sent... maybe 8 bit (1byte) to send a character? (just a wild guess) that would make 1917 / ( 160* 8 )=1.5... now ad some extra info in the headers to tell it's a pic msg and other things......

but that's just my idea....


-=K=-

[slikmik]

Bloody good point!

8bits = 1 byte and a byte needed for letters and simply bits needed for pixels i agree

Anybody confirm?

Mike

[GeeZuZz]

Anyway, maybe the picture message is compressed?

[pedjulino]

Hi,

friends i think that is easy problem Nokia phone when send pic msg convert this msg in hex cod.hex cod is small (zipped) and other phone know(recognize) this hex cod!
Example:
run U in smart sms and see this cod.;)

regards

[DavieB]

LMAO!

Ok here's how it works..

Each character takes 7bits, not 8. The reason for this is 7bits == 128 possible combinations. Standard ASCII code consists of only 128 characters so no need for an 8th bit!
Of course, that assumes you're sending ascii and not an extended charset which would use the 8th bit and make your messages only 70chars long (not 160)

As for pictures, you dont need a full byte (8bits) to represent a pixel, only a bit. So a 7bit byte (the space of a character - well not really cos gsm uses 7bit bytes not 8bit but it'd take too long to explain) would hold 7 pixels!

Its kinda lateish so i might have missed something in my explanation - and i KNOW it could be explained better but thats how it works ;)

Rgds all!

[DavieB]

One more thing to add!

Join forumnokia (forum.nokia.com) and you can download the entire specsheets for all these technologies (wap, sms, picture messaging, etc)
Its free and VERY useful for people who ask such technical questions ;)

Rgdz (again.. lol)

[slikmik]

Cheers Davie B you are the guy in the know :)

Thanks for clearing it all up for us

Mike

[NokDoc]

Hi,

Indeed, the size of the logos is directly related to the sms size!

As basic, one sms has 140 bytes available for user info.

72 x 14 = 1008 pixels, 1008/8 bit per byte = 126 bytes.
Leaving us 14 bytes free for the required logo header definition.
(UDHI)

8/7 x 140 = 160 7bits chars.

8/16 x 140 = 70 16bits chars.

Text not uses the headers.

If sending bigger logos/ texts, some 4 bytes from the 126 will be used for the extra concat info.

So the bigger logos are just a tiny bit smaller as expected.

Btw, nice topic!

NokDoc

[slikmik]

Thank you NokDoc for clearing that up ;)

The new Nokia 7650 as everybody knows has MMS - Multimedia Message Sending - but how does it send it? Is it a case of several SMS Messages also or a long stream... ?

How much are Operators charging to send Pictures?

Im just curious as give it 2 or 3 years and we'll be sending pics to each other as standard in our everyday life! :)

Mike

[DavieB]

I wouldn't even say 2 - 3 years!
It took 2 - 3 years for phones to hit the mainstream but soon after we all used sms! Phones are already mainstream so its only a (small) matter of time!

MMS is sent thru (at least on SonyEricsson T68i) an mms server on the internet. Large MMS message files cannot be sent by a normal data/wap connection as timeouts are so low (as are speeds) that the message wouldn't go out quick enough - therefor it's aimed at GPRS (which is charged by the megabyte by the operator).
So it would depend on the content of the message (thats why MMS supporting phones let you review this before sending!)

Rgds

[slikmik]

Wow exciting isn't it how technology is coming on so fast :)

And we are here personalising it all and reversing it ;)

So how big are the MMS pictures then? (resolution)
You say charged by the Megabyte - any idea how much?

Are they instant like Texts?

SOrry for all the questions just interested and curious as soon as you say we may all be using MMS and text messages may be OLD news :p

Mike

[DavieB]

Hey dont worry!

I dont have the actual charges right here but they ARE quite expensive :/

Tho so were wap calls over gsm to start with so I expect it will go down (or no-one will really use it will they!)

The MMS messages have no fixed resolution. They dont quite work that way.
Their like mini "scripts" - you get a list of elements (ringtones, voice recordings, pictures, text, colors, etc) which you arrange on pages and setup timing for, so your message is played back exactly as intended!

Try getting hold of a SonyEricsson T68i and play with the mms menu (I'm on PAYG o2 so can't send them but the demos and even making my own are quite convincing!)!

The pictures themselves are of no fixed resolution afaik - the supporting phones have to be able to recieve any size (as long as its the correct format) and let you scroll around the screen (this can be seen by opening a large picture over wap on SeT68i - you use the joystick to scroll around the picture :D)

Of course the smaller the picture you send, the smaller the MMS and therefor the less you are charged (well, the plans I have seen work by a system where you purchase an allocation of "bandwidth" - a few MB - and use it up)

If there anything else - reply again (I'm subscribed to the thread and will respond asap)

Regards ;)

[slikmik]

Thanks again for clearing some things up Davie B

Your right when wap first became the rage it was rather pricey but as we are both on o2 im sure you know the FREE 915000 wap number which is handy ;)

So i take it the operator has to support the MMS messages then?
As you say you cannot send them on o2 (?!)

So for example any MMS enabled fones can "talk" to each other so to speak? As in can a noki a7650 send a picture to an Ericsson t68i ?

Cheers once again :P

Mike

[DavieB]

Yehp - MMS is a fully fledged standard supported by all major manufacturers (unlike the shortlived EMS which didn't recieve such wide support!)

Yeh, sending MMS doesn't require operator support AFAIK (you can choose you're own mms "server" on T68i!) but it seems to recieve your operator would in some way need to know how to handle these messages!

It's quite late atm so i've probs missed some questions.. If theres anything else reply again and I'll reply back abt 6/7pm tomorrow!

Regards ;)