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Jetson Nano Wiki
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Getting Started
===============

**Hardware Required:**

.. image:: extra/hardware-requirements-1.jpg
      :align: center

.. image:: extra/hardware-requirement-2.jpg
      :align: center

Flashing the image
-------------------

You can flash the image using either: 

1) Commandline

2) GUI

Using commandline
~~~~~~~~~~~~~~~~~~

.. code-block:: shell

    unzip JetsonNano-shunya-xxxx-image-0.1.zip
    cd JetsonNano-shunya-xxxx-image-0.1

.. note:: Please replace xxxx with desktop or console dependending on the image you downloaded

**If you are using a built in Memory card reader then use the command below:**

.. code-block:: shell

    sudo dd if=shunya-xxxx-image-jetson-nano.img of=/dev/mmcblk0 status=progress

**OR**

If you are using a USB SD-Card adapter use the command below:

.. code-block:: shell

    sudo dd if=shunya-xxxx-image-jetson-nano.img of=/dev/sdx status=progress

.. note:: Please replace x in /dev/sdx with your device(eg /dev/sdb)

Using GUI
~~~~~~~~~~

- **Step 1:Right click on the zip file downloaded and select Extract here**
- **Step 2:Once the image is unzipped double click on the unzipped image folder in which you will find the image and release info**
- **Step 3:Right click on the image**
- **Step 4:Select Open with -> Disk image writer**
- **Step 5:Choose Destination as SD Card Reader**
- **Step 6:Enter your password**

Networking
===========

**Network Devices available:**

- Ethernet

Using a Camera on Jetson-Nano
==============================

Using GStreamer
---------------

**To record a video in the avi format use the following command**

.. code-block:: shell

    gst-launch-1.0 v4l2src ! avimux ! filesink location=filename.avi -e

**To record a video in the mkv format use the following command**

.. code-block:: shell

    gst-launch-1.0 -e v4l2src ! videoconvert ! matroskamux ! filesink location=filename.mkv 

.. note:: Device number might change so be careful.

Using FFMPEG
-------------

To install ffmpeg use the following command:

.. code-block:: shell

   sudo apt install ffmpeg

**To check the index of the USB use v4l-utils.You can install it and get the index using the commands below:**

.. code-block:: shell

   sudo apt install v4l-utils
   v4l2-ctl --list-devices

**To record a video using ffmpeg the following command can be used:**

.. code-block:: shell

   ffmpeg -i /dev/video0 filename.avi

**OR**

.. code-block:: shell

    ffmpeg -f v4l2 -video_size 640x480 -i /dev/video0 -c:v libx264 filename.mp4

Sound on Jetson-Nano
=====================

Sound recording and playback is tested using a USB Mic and a Speaker connected to USB Sound Adapter. 

.. note:: Device and card numbers might change so be careful.

Sound Recording
---------------

To list the recording devices you can use this command:

.. code-block:: shell

   arecord -l

To record a wav file you can use the following command:

.. code-block:: shell

   arecord -vv -Dplughw:2,0 -f dat filename.wav


Sound Playback
--------------

To list the playback devices use this command:

.. code-block:: shell

   aplay -l

To playback a wav file from the Speaker connect to USB Sound Adapter use the following command:

.. code-block:: shell

   aplay -vv --device=hw:2,0 filename.wav

OpenCV on Jetson-Nano
======================

Install **OpenCV-3.3**
----------------------

.. code-block:: shell

   sudo opkg install python3-opencv

Test **OpenCV-3.3**
-------------------

.. code-block:: shell
   :linenos:

    sudo opkg install git
    git clone https://github.com/shunyaos/object-recognition-dnn.git
    cd object-recognition-dnn
    python3 detect.py

Test Outcome 
-------------

.. image:: extra/jetson-nano-test-opencv.png
      :align: center

Resize Rootfs-Partition of Jetson-Nano
=======================================

**If you want to resize the image use the commands given below**

.. code-block:: shell
   :linenos:

    $ sudo parted /dev/mmcblk0
    (parted) resizepart 1                                                     
    Warning: Partition /dev/mmcblk0p1 is being used. Are you sure you want to continue?
    Yes/No? Yes                                                               
    End?  [2147MB]? -34s 
    (parted) quit

    $ sudo partprobe
    $ sudo resize2fs /dev/mmcblk0p1

Release info
============

**Shunya O/s Version: 0.1-Beta**

**Kernel Version: 4.9.140**

**Bootloader: U-BOOT**

**Bootloader Version:2016.07**

**Desktop Environment (if applicable): XFCE**