V4l2-ctl Cannot Capture Raw Data on Nvidia Jetson Orin Nano Dev Board

Issue Overview

Users of the Nvidia Jetson Orin Nano Dev board are experiencing difficulties capturing raw data using v4l2-ctl, despite successful video display through Gstreamer. The issue occurs with an IMX678 800W sensor on the Orin Nano 8GB running r35.4.1. When attempting to capture raw data, the process fails, and error messages are logged indicating discarded frames.

Possible Causes

1. Driver Compatibility: The current camera driver may not fully support raw data capture for the IMX678 sensor on the Jetson Orin Nano platform.

2. Configuration Mismatch: There could be a mismatch between the v4l2-ctl command parameters and the sensor’s supported modes.

3. Firmware Issues: The camera or system firmware may have bugs or limitations affecting raw data capture.

4. Hardware Limitations: There might be hardware constraints on the Jetson Orin Nano that interfere with raw data capture from the IMX678 sensor.

5. Software Conflicts: Other running processes or software components could be interfering with the v4l2-ctl capture process.

Troubleshooting Steps, Solutions & Fixes

1. Verify Sensor Support:

   • Check the IMX678 sensor documentation to confirm support for raw data capture in the desired format.
   • Ensure the sensor driver is up-to-date and compatible with the Jetson Orin Nano.

2. Adjust v4l2-ctl Parameters:

   • Modify the v4l2-ctl command to match the exact capabilities of the sensor:

     v4l2-ctl -d /dev/video0 --set-fmt-video=width=3856,height=2176,pixelformat=RG12 --set-ctrl bypass_mode=0 --stream-mmap
     

   • Remove the gain and exposure settings initially to isolate the issue.

3. Check Supported Formats:

   • Run v4l2-ctl -d /dev/video0 --list-formats-ext to verify supported formats and resolutions.
   • Ensure the chosen format (RG12) is listed and supported at the desired resolution.

4. Analyze Error Messages:

   • Review the error messages, particularly the "corr_err: discarding frame" errors.
   • These may indicate timing or synchronization issues between the sensor and the capture system.

5. Investigate Gstreamer Success:

   • Analyze the working Gstreamer command:

     gst-launch-1.0 nvarguscamerasrc sensor-id=0 ! 'video/x-raw(memory:NVMM), width=3856, height=2176, format=(string)NV12, framerate=(fraction)30/1' ! nvvidconv ! 'video/x-raw,width=768, height=432' ! fpsdisplaysink text-overlay=1 video-sink=xvimagesink sync=0 -v
     

   • Note that it uses NV12 format, which differs from the RG12 format attempted with v4l2-ctl.

6. Try Alternative Formats:

   • Attempt capture with different pixel formats supported by the sensor, such as NV12 or UYVY.

7. Enable Debug Messages:

   • Follow the steps to enable more debug messages as suggested in the Jetson documentation:
     https://elinux.org/Jetson/l4t/Camera_BringUp#Steps_to_enable_more_debug_messages

8. Check for Firmware Updates:

   • Look for any available firmware updates for the Jetson Orin Nano that might address camera capture issues.

9. Investigate Sensor Driver:

   • If possible, modify the sensor driver to report a slightly different resolution (e.g., 3856×2177) to see if it resolves the issue.
   • This may help identify if there’s a off-by-one error in the driver or capture system.

10. Consult Nvidia Developer Forums:

    • Post detailed information about the issue, including command outputs and error logs, on the Nvidia Developer Forums for expert assistance.

11. Consider Alternative Capture Methods:

    • If v4l2-ctl continues to fail, explore using NVIDIA’s libargus API or other camera capture libraries that might offer better compatibility with the Jetson platform.

Remember to document all changes and their effects during troubleshooting. If the issue persists after trying these steps, it may require escalation to Nvidia support or further investigation into the specific interaction between the IMX678 sensor and the Jetson Orin Nano platform.