linux/linux-5.18.11/Documentation/userspace-api/media/v4l/pixfmt-sdr-pcu18be.rst

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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
.. _V4L2-SDR-FMT-PCU18BE:
******************************
V4L2_SDR_FMT_PCU18BE ('PC18')
******************************
Planar complex unsigned 18-bit big endian IQ sample
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.
.. flat-table::
:header-rows: 1
:stub-columns: 0
* - Offset:
- Byte B0
- Byte B1
- Byte B2
- Byte B3
* - start + 0:
- I'\ :sub:`0[17:10]`
- I'\ :sub:`0[9:2]`
- I'\ :sub:`0[1:0]; B2[5:0]=pad`
- pad
* - start + 4:
- I'\ :sub:`1[17:10]`
- I'\ :sub:`1[9:2]`
- I'\ :sub:`1[1:0]; B2[5:0]=pad`
- pad
* - ...
* - start + offset:
- Q'\ :sub:`0[17:10]`
- Q'\ :sub:`0[9:2]`
- Q'\ :sub:`0[1:0]; B2[5:0]=pad`
- pad
* - start + offset + 4:
- Q'\ :sub:`1[17:10]`
- Q'\ :sub:`1[9:2]`
- Q'\ :sub:`1[1:0]; B2[5:0]=pad`
- pad