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1.. -*- coding: utf-8; mode: rst -*-
2.. _V4L2-SDR-FMT-PCU20BE:
3
4******************************
5V4L2_SDR_FMT_PCU20BE ('PC20')
6******************************
7
8Planar complex unsigned 20-bit big endian IQ sample
9
10Description
11===========
12
13This format contains a sequence of complex number samples. Each complex
14number consist of two parts called In-phase and Quadrature (IQ). Both I
15and Q are represented as a 20 bit unsigned big endian number stored in
1632 bit space. The remaining unused bits within the 32 bit space will be
17padded with 0. I value starts first and Q value starts at an offset
18equalling half of the buffer size (i.e.) offset = buffersize/2. Out of
19the 20 bits, bit 19:2 (18 bit) is data and bit 1:0 (2 bit) can be any
20value.
21
22**Byte Order.**
23Each cell is one byte.
24
25.. flat-table::
26    :header-rows:  1
27    :stub-columns: 0
28
29    * -  Offset:
30      -  Byte B0
31      -  Byte B1
32      -  Byte B2
33      -  Byte B3
34    * -  start + 0:
35      -  I'\ :sub:`0[19:12]`
36      -  I'\ :sub:`0[11:4]`
37      -  I'\ :sub:`0[3:0]; B2[3:0]=pad`
38      -  pad
39    * -  start + 4:
40      -  I'\ :sub:`1[19:12]`
41      -  I'\ :sub:`1[11:4]`
42      -  I'\ :sub:`1[3:0]; B2[3:0]=pad`
43      -  pad
44    * -  ...
45    * - start + offset:
46      -  Q'\ :sub:`0[19:12]`
47      -  Q'\ :sub:`0[11:4]`
48      -  Q'\ :sub:`0[3:0]; B2[3:0]=pad`
49      -  pad
50    * - start + offset + 4:
51      -  Q'\ :sub:`1[19:12]`
52      -  Q'\ :sub:`1[11:4]`
53      -  Q'\ :sub:`1[3:0]; B2[3:0]=pad`
54      -  pad
55