2.11.7. V4L2_SDR_FMT_PCU18BE ('PC18')¶
Planar complex unsigned 18-bit big endian IQ sample
2.11.7.1. Description¶
This format contains a sequence of complex number samples. Each complex number consist of two parts called In-phase and Quadrature (IQ). Both I and Q are represented as a 18 bit unsigned big endian number stored in 32 bit space. The remaining unused bits within the 32 bit space will be padded with 0. I value starts first and Q value starts at an offset equalling half of the buffer size (i.e.) offset = buffersize/2. Out of the 18 bits, bit 17:2 (16 bit) is data and bit 1:0 (2 bit) can be any value.
Byte Order. Each cell is one byte.
Offset: | Byte B0 | Byte B1 | Byte B2 | Byte B3 |
---|---|---|---|---|
start + 0: | I'0[17:10] | I'0[9:2] | I'0[1:0]; B2[5:0]=pad | pad |
start + 4: | I'1[17:10] | I'1[9:2] | I'1[1:0]; B2[5:0]=pad | pad |
... | ||||
start + offset: | Q'0[17:10] | Q'0[9:2] | Q'0[1:0]; B2[5:0]=pad | pad |
start + offset + 4: | Q'1[17:10] | Q'1[9:2] | Q'1[1:0]; B2[5:0]=pad | pad |