E.4 2-bit greyscale bitmap

23.0403GPPRelease 17Technical realization of the Short Message Service (SMS)TS

The user-defined 2-bit greyscale 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.The pair of bits at the MSB represents the leftmost pixel of the four defined in an octet.

The colour values are encoded as follows:

Bit Value Colour
00 Black
01 Dark Grey
10 Light Grey
11 White