How to debug 390 sensor without ISP

Hi teams

Recently we debugged imx390 on Xavier.
We have used our own application to get the raw like as below:

We want to use NVIDIA’s own ISP to process raw data.
How should we use the ISP ? Mark the red part in the picture, Like below:


hello JCap,

please note that, there’re two approaches for access the camera stream. (1) VI-mode and (2) VI-bypass mode.

(1) VI-mode.
by having v4l2 standard control to access the camera stream (i.e. v4l2-ctl). this direct v4l2 control use V4L2 API, it’s VI kernel driver to handle the sensor programming. we usually use this approach to validate sensor drivers.

(2) VI-bypass mode.
please use libargus to access the camera stream. (i.e. gstreamer, argus_camera). it’s [Camera Core] to provide all controls and perform all the process between application and sensor drivers.

please check developer guide for reference, Approaches for Validating and Testing the V4L2 Driver.

Hi JerryChang

When I use v4l2-ctl to get the camera shows Data output is normal。lie below:

1) But when I use gst to get data,it shows below error.

2) If I want to display camera data in real time, how can I use ISP to convert raw data, such as uyvy

hello JCap,

you’re not able to enable v4l2src to access bayer sensor types.
please enable GStreamer with the nvarguscamerasrc plugin,
for example,
gst-launch-1.0 nvarguscamerasrc ! ‘video/x-raw(memory:NVMM), width=1920, height=1080, format=(string)NV12, framerate=(fraction)30/1' ! nvoverlaysink -e

Hi JerryChang

When I use command of “gst-launch-1.0 nvarguscamerasrc ! ‘video/x-raw(memory:NVMM), width=1920, height=1080, format=(string)NV12, framerate=(fraction)30/1’ ! nvoverlaysink -e”, it shows error and did not display as below:

When I use our application to get one frame,it can output raw data.

What’s wrong with that ?

hello JCap,

I don’t know what’s the getOneFrame application done,
however, it should be same as v4l2-ctl since it also capture raw files.

there’s no cameras available error with your nvarguscamerasrc pipeline.
you should dig into the property settings, please check Sensor Pixel Clock especially.
please also refer to Debugging Tips session to examine your sensor drivers.

Hi JerryChang

I got it and I will try to find the reason why there’s no cameras available error with nvarguscamerasrc pipeline
What’s more,Applications like Cheese can directly display images in the original data format or not ?

hello JCap,

Cheese application usually works with webcam, it takes the code flow as VI mode.

please note that, camera sensor driver is the same for both VI mode and VI-bypass mode.
according to my previous comments, post #3, it’s VI-bypass mode to went through [Camera Core] block to use ISP.
you may enable the stream with nvarguscamerasrc plugin or argus_camera application for verification.