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1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2
3.. _V4L2-SDR-FMT-PCU18BE:
4
5******************************
6V4L2_SDR_FMT_PCU18BE ('PC18')
7******************************
8
9Planar complex unsigned 18-bit big endian IQ sample
10
11Description
12===========
13
14This format contains a sequence of complex number samples. Each complex
15number consist of two parts called In-phase and Quadrature (IQ). Both I
16and Q are represented as a 18 bit unsigned big endian number stored in
1732 bit space. The remaining unused bits within the 32 bit space will be
18padded with 0. I value starts first and Q value starts at an offset
19equalling half of the buffer size (i.e.) offset = buffersize/2. Out of
20the 18 bits, bit 17:2 (16 bit) is data and bit 1:0 (2 bit) can be any
21value.
22
23**Byte Order.**
24Each cell is one byte.
25
26.. flat-table::
27 :header-rows: 1
28 :stub-columns: 0
29
30 * - Offset:
31 - Byte B0
32 - Byte B1
33 - Byte B2
34 - Byte B3
35 * - start + 0:
36 - I'\ :sub:`0[17:10]`
37 - I'\ :sub:`0[9:2]`
38 - I'\ :sub:`0[1:0]; B2[5:0]=pad`
39 - pad
40 * - start + 4:
41 - I'\ :sub:`1[17:10]`
42 - I'\ :sub:`1[9:2]`
43 - I'\ :sub:`1[1:0]; B2[5:0]=pad`
44 - pad
45 * - ...
46 * - start + offset:
47 - Q'\ :sub:`0[17:10]`
48 - Q'\ :sub:`0[9:2]`
49 - Q'\ :sub:`0[1:0]; B2[5:0]=pad`
50 - pad
51 * - start + offset + 4:
52 - Q'\ :sub:`1[17:10]`
53 - Q'\ :sub:`1[9:2]`
54 - Q'\ :sub:`1[1:0]; B2[5:0]=pad`
55 - pad