.. _SD.CameraDevelopment.ArgusNvrawTool:

.. include:: /content/swdocs.rsts

.. spelling::
   lps
   decompanding
   Libargus
   Omnivision
   compandingLut
   companding
   decompanding
   headerless
   linearization
   linearize
   lps
   nvargus
   nvm
   nvraw
   pwlinfo
   pwl
   sensorinfo
   skipframes
   th
   ubuntu
   writeToFile
   yuv


Argus NvRaw Tool
!!!!!!!!!!!!!!!!

    **Applies to**: Jetson Xavier NX and Jetson AGX Xavier series

    .. todo:: Does it also support Jetson AGX Orin? If so, the "applies to" may be omitted.

Argus NvRaw (``nvargus_nvraw``) is a Bayer raw command line interface (CLI)
capture tool for the Jetson platform. It saves a captured image and its
metadata in a file using nvraw format, described below. It can also save
a captured image in JPEG, YUV, and headerless raw formats. It accepts
user-specified manual exposure control parameters.

You can use Argus NvRaw to initiate a capture after auto white balance
(AWB )and auto exposure (AE) convergence have been achieved by providing
a large number of frames to be skipped.

**nvraw format**, also called **Bayer raw format**, is an NVIDIA
proprietary file format for saving Bayer Raw image captures and
associated metadata. An nvraw file has a file extension of ``.nvraw``. If
the image contains multiple exposures, as from HDR image captures, an
nvraw file can save the individual exposures as well.

nvraw files are used mainly for tuning and improving image quality
during camera driver development. Hence, Argus NvRaw is targeted to
camera driver developers who have engaged a scaling partner to assist
with tuning a driver for optimum image quality. By capturing nvraw
images, you can provide data that your partner can use to tune the
camera driver.

Prerequisites for Use
@@@@@@@@@@@@@@@@@@@@@

You need the following hardware and operating system to perform camera
software development:

- An |NVIDIA(r)| |Jetson Xavier(tm) NX| or |Jetson AGX Xavier(tm)| series device.

  .. todo:: Orin?

- Jetson Linux installed on the Jetson device.

You need the following software packages on the Jetson device:

- NVIDIA Libargus Camera API (a part of the |NVIDIA JetPack(tm)| SDK
  For more information about JetPack SDK, see the page
  `Introduction to JetPack <https://docs.nvidia.com/jetson/jetpack/introduction/index.html>`__
  in
  `NVIDIA JetPack SDK <https://docs.nvidia.com/jetson/jetpack/index.html>`__.

-  A functional camera sensor driver.

Camera Sensor Modes
@@@@@@@@@@@@@@@@@@@

Camera sensors can have more than one mode. Each mode has a resolution,
frame rate, CSI and dynamic bit depths, and mode type. Each mode is
identified by an unsigned; integer. The first mode is mode 0, and the
last is mode *m*\ |minus|\ 1, where *m* is the number of modes.

Different camera sensors support modes the fall into either or both of
two **mode types**:

- **SDR** (Standard Dynamic Range), also known as **Bayer** mode type.
  This mode type is supported by almost every camera sensor. Image
  pixels are not compressed, and no conversion is needed for rendering
  the image on a viewer.

- **HDR** (High Dynamic Range), also known **WDR** (Wide Dynamic
  Range). This mode type is not as widely supported as SDR. In this
  mode type the camera captures more than one exposure per image. The
  resulting output image may be compressed, in which case a view needs
  information about the compression to recover the original pixel
  information.

  HDR mode has sub-modes, one of which is **WDR PWL** (Wide Dynamic Range
  Piecewise Linear). In this sub-mode, images are compressed based on a
  set of x and y coordinates, reducing the reduced number of bits needed
  to hold pixel data. The same set of coordinates are used to decompress
  the pixels and recover the original data.

When you run the ``nvargus_nvraw`` command, you select a mode with a command line option. (See
`nvargus_nvraw Usage <#nvargus-nvraw-usage>`__.)
If you select an HDR mode, you may have to enter additional mode-specific information on the command line.

nvargus_nvraw Command
@@@@@@@@@@@@@@@@@@@@@

This section describes the usage of the ``nvargus_nvraw`` command and shows
several examples of its use.

nvargus_nvraw Usage
###################

The usage of ``nvargus_nvraw`` is::

    $ nvargus_nvraw [<options>]

Where ``<options>`` is an optional set of one or more command line options.
The table below describes options for this command.

+----------------------+------------------------------------+----------------------+
| Option               | Description                        | Default value        |
+======================+====================================+======================+
| --c <sensor_id>      | Specifies the zero-based ID of the | 0                    |
|                      | sensor to be used.                 |                      |
+----------------------+------------------------------------+----------------------+
| --mode <number>      | Specifies the zero-based mode      | 0                    |
|                      | number of the sensor.              |                      |
+----------------------+------------------------------------+----------------------+
| --file <file>        | Specifies the complete pathname    | —                    |
|                      | for the NVRAW output file.         |                      |
+----------------------+------------------------------------+----------------------+
| --exp<n>             | Specifies an exposure set          | Current value in the |
| "<time>,<gain>"      | containing manual values for       | sensor driver or     |
|                      | exposure time and sensor gain. The | register. This value |
|                      | option’s value is described in the | is not predictable.  |
|                      | section                            |                      |
|                      | `Specify an exposure set set (the  |                      |
|                      | --exp<n> option) <#specify-an-     |                      |
|                      | exposure-set-the-exp-n-option>`__, |                      |
|                      | below.                             |                      |
+----------------------+------------------------------------+----------------------+
| --verbosity <level>  | Specifies the verbosity of printed | error                |
|                      | output. Possible values, from      |                      |
|                      | least to most verbose, are         |                      |
|                      | ``error``, ``warning``, ``info``,  |                      |
|                      | and ``debug``.                     |                      |
|                      |                                    |                      |
|                      | Verbosity levels are cumulative.   |                      |
|                      | For example, the printed output    |                      |
|                      | for ``info`` includes all of the   |                      |
|                      | printed output for ``error`` and   |                      |
|                      | ``warning``.                       |                      |
+----------------------+------------------------------------+----------------------+
| --pwlinfo <pwl_file> | Specifies the pathname a file that | —                    |
|                      | defines a set of PWL (piecewise    |                      |
|                      | linear) decompanding points to be  |                      |
|                      | stored in the NVRAW image metadata |                      |
|                      | after capture. Used with PWL       |                      |
|                      | captures if the sensor driver does |                      |
|                      | not provide PWL decompanding       |                      |
|                      | points to ``nvargus_nvraw``.       |                      |
|                      |                                    |                      |
|                      | Each point in the PWL file is      |                      |
|                      | defined in the form:               |                      |
|                      |                                    |                      |
|                      | linearization.compandingLut[n].x = |                      |
|                      | <x_value>;                         |                      |
|                      |                                    |                      |
|                      | linearization.compandingLut[n].y = |                      |
|                      | <y_value>;                         |                      |
|                      |                                    |                      |
|                      | Where *n* is the index of a        |                      |
|                      | decompanding point (0 to 8),       |                      |
|                      | ``<x_value>`` is the compressed    |                      |
|                      | value at that point, and           |                      |
|                      | ``<y_value>`` is the corresponding |                      |
|                      | decompressed value.                |                      |
+----------------------+------------------------------------+----------------------+
| --override           | Overrides certain errors. See      | Disabled             |
|                      | `Specify Error Override (the       |                      |
|                      | --override option) <#to-specify-   |                      |
|                      | error-override-the-override-       |                      |
|                      | Option>`__                         |                      |
|                      | , below.                           |                      |
+----------------------+------------------------------------+----------------------+
| --ts                 | Enables time stamp printing during | —                    |
|                      | logging.                           |                      |
+----------------------+------------------------------------+----------------------+
| --format <list>      | Specifies one or more file formats | nvraw                |
|                      | in which to save output. See       |                      |
|                      | `Specify Output Format (the        |                      |
|                      | --format Option) <#specify-output- |                      |
|                      | format-the-format-option>`__,      |                      |
|                      | below.                             |                      |
+----------------------+------------------------------------+----------------------+
| --skipframes <count> | Number of frames to be skipped     | 90                   |
|                      | before the final frame that is     |                      |
|                      | saved to storage.                  |                      |
|                      |                                    |                      |
|                      | Example::                          |                      |
|                      |                                    |                      |
|                      |     --skipframes 40                |                      |
+----------------------+------------------------------------+----------------------+
| --help               | Prints a runtime help menu         |                      |
|                      | containing all of the command line |                      |
|                      | options specified in this table.   |                      |
+----------------------+------------------------------------+----------------------+
| --lps                | Prints a list of available sensors |                      |
|                      | and their supported resolutions.   |                      |
+----------------------+------------------------------------+----------------------+
| --sensorinfo         | Prints information about the       | —                    |
|                      | selected sensor and mode.          |                      |
+----------------------+------------------------------------+----------------------+


Basic Examples
##############

This section presents several simple examples of the ``nvargus_nvraw``
command. Later sections present additional examples for various types of
use.


Specify an Exposure Set: the --exp<n> Option
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Use the ``--exp<n>`` option to specify an exposure set containing manual
values for exposure time and sensor gain.

A high dynamic range (HDR) sensor can capture several exposures for each
image, numbered from 0 to *N*\ |minus|\ 1, where *N* is the number of exposures
captured. Thus the ``--exp0`` option specifies the exposure set to be used
for exposure 0, ``--exp1`` specifies the exposure set for exposure 1, and so on. The section
`Display Further Information for a Specific Sensor <#display-further-information-for-a-specific-sensor>`__
explains how to determine the number of exposures a particular HDR sensor can capture.

The ``--exp<n>`` option has the format::

    --exp<n> "<time>,<gain>"

Where:

- ``<n>`` is the zero-based number of an HDR exposure.

  Although the ``--exp<n>`` option is designed to take multiple exposures, the value of ``<n>`` currently may not be greater than 0. Exposure time and sensor gain for exposure 1 and following are determined by the HDR ratio internally in ``nvargus_nvraw``.

- ``<time>`` is the exposure time of exposure *n*, in seconds.

- ``<gain>`` is the sensor gain for exposure *n*, e.g. 1.0 for no gain, 2.0
  for 2x gain, etc.

  Spaces between ``<time>`` and ``<gain>`` are allowed but not required.

  If any value is omitted, the tool uses the value in the sensor driver or register. This value is not predictable. If ``<gain>`` is omitted, the trailing comma may be omitted.


Specify Error Override: the --override Option
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The override option overrides certain errors. If an overridden error
occurs, Argus NvRaw continues to run as if there were no error.

Currently this option overrides one error:

- If the frame is compressed, the decompression information must be
  provided by the driver or by a user-supplied file specified by the ``--pwlinfo`` command line parameter. If decompression information is not provided by either source, that is an error.

The ``--override`` option is useful while you are bringing up the driver if
you must capture an image, then gather some data to define PWL
decompanding points to provide to the driver. This option ensures that
the capture can proceed even though PWL decompanding points are not yet
available.


Specify Output Format: the --format Option
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The ``--format`` option specifies a comma-separated list of one or more file
formats in which to save output. The file formats must be chosen from this table:

+-------------------------+-------------------------+----------------+
| File format             | Type of file            | File extension |
| (``--format`` option)   |                         |                |
+=========================+=========================+================+
| nvraw                   | nvraw_v3 format file    | ``.nvraw``     |
+-------------------------+-------------------------+----------------+
| yuv                     | YUV 8-bit 4:2:0 format  | ``.yuv``       |
|                         | file                    |                |
+-------------------------+-------------------------+----------------+
| jpg                     | JPEG format file        | ``.jpg``       |
+-------------------------+-------------------------+----------------+
| raw                     | Headerless raw format   | ``.raw`` and   |
|                         | file and its            | ``.txt``       |
|                         | corresponding metadata  |                |
|                         | file                    |                |
+-------------------------+-------------------------+----------------+

For example, this option specifies output files in nvraw_v3, JPG, and
YUV 8 bit 4:2:0 formats::

    $ --format "nvraw, jpg, yuv"

In the following example, this option specifies output files in nvraw_v3
and headerless Bayer raw formats::

    $ --format "nvraw, raw"

Each output file has the basename specified by the ``--file`` option. If the
``--format`` option is present and its value is ``jpg`` or ``yuv``, the output file
has the extension ``.jpg`` or ``.yuv``; if its value is ``nvraw``, the output file
has the extension ``.nvraw``.


Displaying Sensor Information
#############################

The first example lists the configurations available for a specified
sensor. The second one displays detailed information about a specified
configuration.

List Available Sensor Configurations: the --lps Option
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Enter this command to list the available sensor configurations::

    $ nvargus_nvraw --lps

For an OV5693 sensor, the command displays this output::

    nvargus_nvraw version 1.0.0
    Number of supported sensor entries 3
    Entry Source Mode Uniquename Resolution FR BitDepth SensorMode
    Index CSI Dyn
    0 0 0 2592x1944 30 10 10 Bayer
    1 0 1 2592x1458 30 10 10 Bayer
    2 0 2 1280x 720 120 10 10 Bayer

All of this sensor’s modes are the SDR (Bayer) mode type, each with a
different resolution and or frame rate.

For an IMX185 sensor, the command displays this::

    nvargus_nvraw version 1.0.0
    Number of supported sensor entries 5
    Entry Source Mode Uniquename Resolution FR BitDepth SensorMode
    Index CSI Dyn
    0 0 0 1920x1080 30 12 12 Bayer
    1 0 1 1920x1080 30 10 10 Bayer
    2 0 2 1920x1080 60 12 12 Bayer
    3 0 3 1920x1080 60 10 10 Bayer
    4 0 4 1920x1080 30 12 16 Bayer_WDR_PWL

Modes 0 through 3 are regular SDR (or Bayer) mode type; mode 4 is a WDR
PWL mode.

Display Further Information for a Specific Sensor
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Enter this command::

    $ nvargus_nvraw --c <sensor_id> --mode <mode_number> --sensorinfo

This is an example of an actual command for SDR mode::

    $ nvargus_nvraw --c 0 --mode 0 --sensorinfo

The command displays output like this::

    nvargus_nvraw version 1.0.0
    Number of sensors 1, Number of modes for selected sensor 5

    Selected sensor: imx185_bottom_liimx185 ID 0 Mode 0
    Number of exposures 1
    Index Exposure time Range Sensor Gain Range
    0 0.000030 - 0.660000 1.00 - 251.19

This is an example of an actual command, for WDR PWL mode::

    $ nvargus_nvraw --c 0 --mode 4 --sensorinfo

The command displays output like this::

    nvargus_nvraw version 1.0.0
    Number of sensors 1, Number of modes for selected sensor 5

    Selected sensor: imx185_bottom_liimx185 ID 0 Mode 4
    Number of exposures 1
    Index Exposure time Range Sensor Gain Range
    0 0.002433 - 0.660000 1.000000 - 3.981071
    1 0.000152 - 0.041250 1.000000 - 3.981071

    HDR Ratio: 16.00
    Note: The ratio between the Exposure Time in Exposure 0 and
          the Exposure Time in Exposure 1 will be equal to HDR Ratio

Capturing Images
################

The first following example captures an SDR image. The second captures a WDR PWL image.

Capture a Standard Dynamic Range (SDR) NVRAW Image
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An SDR image contains a single exposure. It is designated “exposure 0,”
so you refer to its properties with the option ``--exp0``. You can
optionally specify manual exposure parameters during the capture.

Enter this command::

    $ nvargus_nvraw --c <sensor_id> --mode <mode_number> --exp0 "<time>,<gain>" --file <filename>

Where:

- ``<sensor_id>`` is the zero-based ID of the sensor to be used
- ``<mode_number>`` is the zero-based mode number of the mode to be used
- ``--exp0`` specifies the number of the image to capture (always 0 for an SDR image)
- ``<time>`` is the capture’s exposure time in seconds
- ``<gain>`` is the gain to apply to the capture
- ``<filename>`` is the name the capture file is to have.

The command specifies a single ``--exp<n>`` option, which references one of
the exposures provided by the sensor. To display a list of exposures
available for a sensor, use the ``--sensorinfo`` option shown above.

If you do not specify ``--exp<n>``, the command uses the sensor driver’s
current values.

This is an example of an actual command::

    $ nvargus_nvraw --c 0 --mode 0 --file /home/ubuntu/sample.nvraw --exp0 "0.000034, 5"

The command displays output like this::

    argus_nvraw version 1.0.0
    +-------------- Exposure info results -------------+
    | Exposure     | Exposure Time     | Sensor Gain   |
    | 0            | 0.000034          | 5.00          |
    +--------------------------------------------------+
    writeToFile: file /home/ubuntu/sample.nvraw is successfully created

.. todo:: Something squashed the whitespace in the output. I reconstructed it by guess.


Capture a WDR PWL NVRAW image without Specifying Manual Exposure Information
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Enter a command like the following one, modifying it as appropriate to
suit your use case. Use the mode number that specifies WDR PWL
capability for your camera sensor::

    $ nvargus_nvraw --c 0 --mode 4 --file /home/ubuntu/sample.nvraw

The command displays output similar to that shown below. This example
shows that the camera is capturing two exposures per image, with
exposure time and sensor gain taken from the sensor driver’s current
values::

    argus_nvraw version 1.0.0
    +------ Exposure info results -----------+
    | Exposure | Exposure Time | Sensor Gain |
    |        0 |      0.033333 |     3.98107 |
    |        1 |      0.002083 |     3.98107 |
    +----------------------------------------+

    HDR Ratio: 16.00
    Note: The ratio between the Exposure Time in Exposure 0 and
          the Exposure Time in Exposure 1 is equal to HDR Ratio
    writeToFile: file /home/ubuntu/sample.nvraw is successfully created

.. todo::
   This example's table is narrower than the previous one. I'm skeptical that the program actually uses different formats, so I suspect data corruption at some point. Table width is determined by the upper and lower borders, which have no embedded runs of spaces, and so could not have been corrupted at the same time as the first table's column positions.


Capture a WDR PWL NVRAW image Specifying Manual Exposure Information
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

Even though HDR mode supports 2 exposures, the user can provide the
manual exposure information of only the first exposure (exp0). Manual
exposure information of the second exposure (exp1) is computed from the
first exposure using the HDR ratio.

This is an example of an actual command::

    $ nvargus_nvraw --c 0 --mode 4 --file /home/ubuntu/sample.nvraw --exp0 0.05671, 2.0"

The command displays output like this::

    argus_nvraw version 1.0.0
    +------ Exposure info results -----------+
    | Exposure | Exposure Time | Sensor Gain |
    |        0 |      0.056710 |     2.00000 |
    |        1 |      0.003544 |     2.00000 |
    +----------------------------------------+
    HDR Ratio: 16.00
    Note: The ratio between the Exposure Time in Exposure 0 and
          the Exposure Time in Exposure 1 is equal to HDR Ratio
    writeToFile: file /home/ubuntu/sample.nvraw is successfully created

The exposure time of the first exposure reflects a user-specified value, and that of the second exposure is 1/16th of the first exposure.


PWL Decompanding Points
$$$$$$$$$$$$$$$$$$$$$$$

The ``nvargus_nvraw`` utility needs a PWL (piecewise linear) decompanding
curve to re-linearize PWL RAW images captured with a PWL sensor.

The utility looks first for a user-provided PWL information file that
contains a set of PWL decompanding points that define the curve. If no
file is provided, it tries to get PWL decompanding points from the
sensor driver. If the sensor driver does not provide PWL decompanding
points either, the utility prints the error “Missing PWL Knee Points”
and terminates.

You can provide PWL decompanding points by storing them in a file, as
described in the following sections.


PWL information file
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You can define a PWL companding curve in a PWL information file. You
specify the file to nvm_nvraw with the pwlinfo option::

    $ nvargus_nvraw --c <sensor_id> --mode <mode_number> --file output_file> --pwlinfo <pwl_file>

The file can define up to nine PWL decompanding points. Each point is
defined by a pair of settings::

    linearization.compandingLut[n].x = <xn>;
    linearization.compandingLut[n].y = <yn>;

Where:

- ``<n>`` is the index of a decompanding point, in the range 0 to 8.
- ``<xn>`` is the compressed value of point ``<n>``.
- ``<yn>`` is the decompressed value of point ``<n>``.

For example, this PWL information file defines two decompanding points::

    linearization.compandingLut[0].x = 10.0;
    linearization.compandingLut[0].y = 23645.0;
    linearization.compandingLut[1].x = 400.0;
    linearization.compandingLut[1].y = 53845.0;

This ``nvargus_raw`` command uses a decompanding file named
``sensor_pwlinfo.txt``::

    $ nvargus_nvraw --c 0 --mode 4 --file /home/ubuntu/sample.nvraw --pwlinfo pwlinfo.txt

The command’s output looks like this::

    nvargus_nvraw version 1.0.0
    capture: Total captured frame count 90
    capture: Successfully read 4 PWL Knee points from user provided file
    /tmp/pwlinfo.txt
    +------ Exposure info results -----------+
    | Exposure | Exposure Time | Sensor Gain |
    |        0 |      0.033333 |     3.98107 |
    |        1 |      0.002083 |     3.98107 |
    +----------------------------------------+
    HDR Ratio: 16.00
    Note: The ratio between the Exposure Time in Exposure 0 and
        the Exposure Time in Exposure 1 is equal to HDR Ratio
    writeToFile: file /home/ubuntu/sample.nvraw is successfully created


Continue to Run after certain Terminal Errors: the --override Option
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Use the command line option ``--override`` to tell the ``nvargus_nvraw`` utility
to override certain ordinarily terminal errors and continue running.

Currently --override controls only one error, "Missing PWL decompanding
points," which means that PWL decompanding points were not available
from either a PWL information file or the camera sensor. For information
about how a PWL information file is created and used, see the section
`Displaying Sensor Information <#displaying-sensor-information>`__.


Capture a JPEG and YUV Image
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A JPEG or YUV file’s name comprises the basename from the ``--file`` option
and the extension ``.jpg`` (for a JPEG file) or ``.yuv`` (for a YUV file). In
case of a ``.yuv`` file, the resolution of the camera sensor is also
incorporated into the basename.

Enter this command::

    $ nvargus_nvraw --c <sensor_id> --mode <mode_number> --file <filename> --format "jpg, yuv"

This is an example of an actual command::

    $ nvargus_nvraw --c 0 --mode 0 --file /home/ubuntu/sample.jpg –-format "yuv, jpg"

It displays output like this::

    argus_nvraw version 1.0.0
    writeToFile_Jpeg: file /home/ubuntu/sample.jpg is successfully created
    writeToFile_Yuv: file /home/ubuntu/sample_2592x1944.yuv is successfully created


Capture a Headerless Bayer Raw Image
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A headerless Bayer raw image file contains only raw pixels. It is
accompanied by a text file that contains the metadata associated with
the image.

This is an example of an actual command for capturing a headerless Bayer
raw image::

    $ nvargus_nvraw --c 0 --mode 0 --file /home/ubuntu/sample -–format "raw"

It displays output like this::

    ``nvargus_nvraw`` version 1.0.0
    capture: Total captured frame count 90
    +------ Exposure info results -----------+
    | Exposure | Exposure Time | Sensor Gain |
    |        0 |      0.033333 |     3.98107 |
    +----------------------------------------+
    writeToFile_HeaderlessRaw: files /home/ubuntu/sample.raw and /home/ubuntu/sample.txt are successfully created


Other Operations
################

This section contains examples that do not belong in any other group.

Specify a Number of Frames to Skip
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You can specify a number of frames to skip before the frame to save to
the storage file by using the –skipframes option.

Enter a command like this::

    $ nvargus_nvraw --c <sensor_id> --mode <mode_number> --file <filename> --skipframes <count>

Where  ``<count>`` is the number of frames to skip.

This is an example of an actual command which skips the first 20 frames
and captures the image in the 21st::

    $ nvargus_nvraw --c 0 --mode 0 --file /home/ubuntu/sample.nvraw skipframes 20

It displays output like this::

    argus_nvraw version 1.0.0
    capture: Total captured frame count 21
    +-------------- Exposure info results -------------+
    | Exposure | Exposure Time | Sensor Gain           |
    | 0        |     0.000034  |    5.00               |
    +--------------------------------------------------+
    writeToFile: file /home/ubuntu/sample.nvraw is successfully created

Limitations
###########

Green JPG and YUV Images
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If you use the ``--format`` option to generate JPEG or YUV format files
using an Omnivision OV5693 sensor, the generated images have a green cast.