2.11.8. V4L2_SDR_FMT_PCU20BE (‘PC20’)¶
Planar complex unsigned 20-bit big endian IQ sample
2.11.8.1. 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 20 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 20 bits, bit 19:2 (18 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[19:12]  | 
I’0[11:4]  | 
I’0[3:0]; B2[3:0]=pad  | 
pad  | 
start + 4:  | 
I’1[19:12]  | 
I’1[11:4]  | 
I’1[3:0]; B2[3:0]=pad  | 
pad  | 
...  | 
||||
start + offset:  | 
Q’0[19:12]  | 
Q’0[11:4]  | 
Q’0[3:0]; B2[3:0]=pad  | 
pad  | 
start + offset + 4:  | 
Q’1[19:12]  | 
Q’1[11:4]  | 
Q’1[3:0]; B2[3:0]=pad  | 
pad  |