NVIDIA Tegra
NVIDIA Tegra Linux Driver Package

Development Guide
28.3 Release


 
Camera Software Development Solution
 
Camera Architecture Stack
Camera API Matrix
Approaches for Validating and Testing the V4L2 Driver
Applications Using libargus Low-level APIs
Applications Using GStreamer with the nvcamerasrc Plugin
Applications Using GStreamer with the nvarguscamerasrc Plugin
Applications Using GStreamer with V4L2 Source Plugin
Applications Using V4L2 IOCTL Directly
ISP Support
Symlinks Changed by Mesa Installation
Other References
This document describes the NVIDIA® Jetson TX1 and TX2 camera software solution and explains the NVIDIA supported and recommended camera software architecture for fast and optimal time to market. Development options are outlined and explained to customize the camera solution for USB, YUV, and Bayer camera support. Additionally, debugging approaches are explored to aid in the development process.
Camera Architecture Stack
The NVIDIA camera software architecture includes NVIDIA components that allow for ease of development and customization:
The camera architecture includes the following NVIDIA components:
libargus—Provides a low-level API based on the camera core stack.
nvcamerasrc—NVIDIA camera GStreamer plugin that provides many options to conrol ISP properties.
nvarguscamerasrc—NVIDIA camera GStreamer plugin that provides options to control ISP properties using the ARGUS API.
v4l2src—A standard Linux V4L2 application that uses direct kernel IOCTL calls to access V4L2 functionality.
NVIDIA provides OV5693 Bayer sensor as a sample. NVIDIA tunes this sensor for the Jetson platform. The drive code, based on the media controller framework, is available at:
./kernel/kernel4.4/drivers/media/i2c/ov5693.c
NVIDIA provides additional sensor support for BSP software releases. Developers must work with NVIDIA certified camera partners for any Bayer sensor and tuning support. The work involved includes:
Sensor driver development
Custom tools for sensor characterization
Image quality tuning
These tools and operating mechanisms are NOT part of the public Jetson Embedded Platform (JEP) Board Support Package release.
For more information on sensor driver development, see the NVIDIA Tegra X1 V4L2 Sensor Driver Programming Guide.
Camera API Matrix
The matrix of the camera APIs available at each camera configuration are as follows.
 
 
 
 
 
Uses Tegra ISP (CSI Interface)
Does not use Tegra ISP (CSI Interface)
USB (UVC) *
(USB Interface)
Camera API
libargus
GStreamer
(GST-nvarguscamerasrc/nvcamerasrc)
V4L2
V4L2
* Drivers are not provided by NVIDIA, you must write the drivers.
Customer can support peripheral bus device such as:
- Ethernet
- Non-UVC USB
Libargus is the perferred path to access the camera.
 
Note:
The default OV5693 camera does not contain an integrated ISP. Use of the V4L2 API with the reference camera records “raw” Bayer data.
Approaches for Validating and Testing the V4L2 Driver
Once your driver development is complete, use the provided tools or application to validate and test the V4L2 driver interface.
For general GStreamer and multimedia operations, see the Multimedia User Guide available from the NVIDIA Embedded Download Center at:
https://developer.nvidia.com/embedded/downloads
Applications Using libargus Low-level APIs
The NVIDIA Multimedia API provides samples that demonstrate how to use the libargus APIs to preview, capture, and record the sensor stream.
The Multimedia API must be installed with NVIDIA JetPack. It cannot be installed as a standalone package. JetPack is available for download from the NVIDIA Embedded Download Center at:
https://developer.nvidia.com/embedded/downloads
To view the Multimedia API Reference, click the API tab at the top of this page.
Applications Using GStreamer with the nvcamerasrc Plugin
Use the nvcamerasrc GStreamer plugin to:
Enable ISP post-processing for Bayer sensors
Perform format conversion
Generate output directly for YUV sensor and USB camera
For example, for a Bayer sensor with the format 1080p/30/BGGR:
Save the preview into the file as follows:
gst-launch-1.0 nvcamerasrc num-buffers=200 sensor-id=0 ! 'video/x-raw(memory:NVMM),width=1920, height=1080, framerate=30/1, format=NV12' ! omxh264enc ! qtmux ! filesink location=test.mp4 -e
Render the preview to an HDMI™ screen as follows:
gst-launch-1.0 nvcamerasrc sensor-id=0 ! 'video/x-raw(memory:NVMM),width=1920, height=1080, framerate=30/1, format=NV12' ! nvoverlaysink -e
Applications Using GStreamer with the nvarguscamerasrc Plugin
Use the nvarguscamerasrc GStreamer plugin supported camera features with ARGUS API to:
Enable ISP post-processing for Bayer sensors
Perform format conversion
Generate output directly for YUV sensor and USB camera
For example, for a Bayer sensor with the format 1080p/30/BGGR:
Save the preview into the file as follows:
gst-launch-1.0 nvarguscamerasrc num-buffers=200 ! 'video/x-raw(memory:NVMM),width=1920, height=1080, framerate=30/1, format=NV12' ! omxh264enc ! qtmux ! filesink location=test.mp4 -e
Render the preview to an HDMI screen as follows:
gst-launch-1.0 nvarguscamerasrc ! ‘video/x-raw(memory:NVMM), width=1920, height=1080, format=(string)NV12, framerate=(fraction)30/1' ! nvoverlaysink -e
Applications Using GStreamer with V4L2 Source Plugin
Using the YUV sensor, or USB camera, to output YUV images without ISP post-processing does not use the NVIDIA camera software stack.
For example, a USB camera with the format 480p/30/YUY2:
Save the preview into a file as follows (based on software converter):
gst-launch-1.0 v4l2src num-buffers=200 device=/dev/video0 ! 'video/x-raw, format=YUY2, width=640, height=480, framerate=30/1' ! videoconvert ! omxh264enc ! qtmux ! filesink location=test.mp4 -ev
Render the preview to a screen as follows:
//export DISPLAY=:0 if you are operating from remote console
gst-launch-1.0 v4l2src device=/dev/video0 ! 'video/x-raw, format=YUY2, width=640, height=480, framerate=30/1' ! xvimagesink -ev
For a YUV sensor with the format 480p/30/UYVY:
Save the preview into a file as follows (based on hardware accelerated converter):
gst-launch-1.0 -v v4l2src device=/dev/video0 ! 'video/x-raw, format=(string)UYVY, width=(int)640, height=(int)480, framerate=(fraction)30/1' ! nvvidconv ! 'video/x-raw(memory:NVMM), format=(string)NV12' ! omxh264enc ! qtmux ! filesink location=test.mp4 -ev
Render the preview to a screen as follows:
//export DISPLAY=:0 if you are operating from remote console
gst-launch-1.0 v4l2src device=/dev/video0 ! 'video/x-raw, format=(string)UYVY, width=(int)640, height=(int)480, framerate=(fraction)30/1' ! xvimagesink -ev
Applications Using V4L2 IOCTL Directly
Use V4L2 IOCTL to verify basic functionality during sensor bringup.
For example, capture from a Bayer sensor with the format 1080p/30/RG10:
v4l2-ctl --set-fmt-video=width=1920,height=1080,pixelformat=RG10 --stream-mmap --stream-count=1 -d /dev/video0 --stream-to=ov5693.raw
ISP Support
To enable ISP support
Built-in to the Camera Core where the release package includes initial ISP configuration files for reference sensors.
Note:
CSI cameras, with integrated ISP and USB camera, can work in ISP bypass mode. Provided ISP support is available for Jetson Developer Kit (OV5693) RAW camera module.
Additional ISP support for other camera modules are supported using third party partners.
Symlinks Changed by Mesa Installation
Installation of Mesa EGL may create a /usr/lib/<ABI_directory>/libEGL.so symlink, overwriting the symlink to the implementation library that must be used instead, /usr/lib/<ABI_directory>/tegra-egl/libEGL.so. This disrupts any client of EGL, including libraries in the release that use it for EGLStreams.
In this release, the symlink is replaced when the system is rebooted, fixing this issue on reboot. Similar workarounds have been applied in previous releases for other libraries such as libGL and libglx.
Other References
For details on integrating with other Jetson Multimedia components using V4L2 or GStreamer, see the Jetson Multimedia API reference for JetPack.
For details on Argus, see the LibArgus JetPack documentation.
For details on building a custom camera solution, see our Preferred Partners Community at:
https://developer.nvidia.com/embedded/community/partners