Appendix "A1" - Message types - OTA bitmap
Introduction
An OTA bitmap is used for various SMS formats: Operator logo, CLI icon, Picture Message, and Downloadable Profile. In most phone 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. Because 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. With picture message and 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 black000000000000000000 <- 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
More information
- A1 - OTA Bitmap
- A2 - Logo del operador I
- A3 - Logo del operador II
- A4 - Tono de llamada
- A5 - Wappush
- A6 - VCalendar
- Apéndice "A7" - Tipos de mensajes - VCard
- A8 - Código de barras
- B - Proveedores de servicios
- C - Números SMSC
- D - Operadores GSM
- Alfabeto E - SMS
- Apéndice "F" - Códigos de error GSM
- G - Cadenas de conexión
- H - Referencias
- I - Información MMSC
- Preguntas frecuentes
- K - Formato SMS