E.5 6-bit colour bitmap
23.0403GPPRelease 17Technical realization of the Short Message Service (SMS)TS
The user-defined 6-bit colour bitmap as integrated in the Extended Object IE is structured as follows:
Octet 8 Horizontal dimension of picture.
This octet shall contain the horizontal number of pixels
Octet 9 Vertical dimension of picture.
This octet shall contain the vertical number of pixels.
Octet 10..n.
Picture data, pixel by pixel from top left to bottom right. The picture data is encoded as a continuous sequence of bits. There shall be no fill bits at the end of each row of data, Fill bits may only be used in the last octet of the picture data. The fill bits in the last octet shall be ignored.
Each pixel colour is represented by 6-bits of data, giving a total of 64 colours. (2 bits of data define the levels of each red, green and blue). The overall pixel colour is a composite of the three RGB values.
The first pair of bits of picture data define the level of red of the topmost, leftmost pixel, the next pair of bits the level of green for this pixel, and the third pair the level of blue for the pixel. The first bit of a pair defining a colour level is the MSB. This is illustrated below.
|
Octet 1 |
|||||||
|
Bit 7 |
Bit 6 |
Bit 5 |
Bit 4 |
Bit 3 |
Bit 2 |
Bit 1 |
Bit 0 |
|
MSB Red Pixel 1 |
LSB Red |
MSB Green Pixel 1 |
LSB Green Pixel 1 |
MSB Blue |
LSB Blue |
MSB Red |
LSB Red Pixel 2 |
|
Octet 2 |
|||||||
|
Bit 7 |
Bit 6 |
Bit 5 |
Bit 4 |
Bit 3 |
Bit 2 |
Bit 1 |
Bit 0 |
|
MSB Green Pixel 2 |
LSB Green Pixel 2 |
MSB Blue |
LSB Blue |
MSB Red |
LSB Red Pixel 3 |
MSB Green Pixel 3 |
LSB Green Pixel 3 |