Mobile message type specification - OTA bitmap SMS
(SMS message type, SMS message format)
Introduction
An OTA bitmap is used for various SMS formats: Operator logo,
CLI
icon, Picture Message, and Downloadable Profile. In most phones the maximum size
of the operator logo and the CLI icon is 72 x 14 pixels, while the maximum size
of the picture
message and the screen saver is 72 x 28 pixels. An OTA bitmap consists of a
bitmap header and bitmap data. The size of the bitmap is specified in the
header.
A typical OTA bitmap (72 x 14 pixels) header is: 00480E01
|
00 |
Infofield |
|
48 |
Width of the bitmap is 72 pixels |
|
0E |
Height of the bitmap is 14 pixels |
|
00 |
Number of colors or grey shades (only one color)
|
The image data is located after the header information and is
encoded as follows. Each semi-octet in the OTA bitmap presents 4 pixels in the
original bitmap. As one row takes 18 semi-octets, the whole 72 x 14
(operator logo and CLI icon) bitmap takes 18 x 14 = 252 semi-octets = 126
octets. Including the picture message and the screen saver, the entire 72 x 28
size bitmap
takes 18 x 28 = 504 semi-octets = 252 octets. For example, if the first four
pixels of the image are 1010 (1 - black, 0 - white), the first semi-octet of the
OTA bitmap data is hex A.
Example:
Here is an example of a simple OTA bitmap (72 x 14 pixels).
In the picture, there are two black lines and several black dots:
FFFFFFFFFFFFFFFFFF <- First line black
000000000000000000 <- Second line white
FFFFFFFFFFFFFFFFFF
000000000000000000
10F000000000000000 <- Fourth pixel of this line is black
and
9-12
000000000000000000 pixels are also black
000000000000000000
000000000000000000
000000000000000000
000000000000000000
000000000000000000
000000000000000000
000000000000000000
000000000000000001 <- Last pixel of this row/bitmap is black
Next page:
Operator logo I.
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