Gstreamer jpeg timestamp or metadata Continue

Hi, it continuation of this topic:


Tell me please:

  1. For gst pipeline with 2(N) cameras argus uses single NvBuffer?
gst-launch-1.0 -v \
 nvarguscamerasrc sensor-id=0 ! 'video/x-raw(memory:NVMM),format=NV12,width=4032,height=3040,framerate=8/1' ! nvjpegenc ! queue ! multifilesink location=cam0_%03d.jpg \
 nvarguscamerasrc sensor-id=1  ! 'video/x-raw(memory:NVMM),format=NV12,width=4032,height=3040,framerate=8/1' ! nvjpegenc ! queue ! multifilesink location=cam1_%03d.jpg
  1. For c++ SDK code with Producers, Consumers and Multisession argus uses single NvBuffer too?
    Mutissesion assumes N buffers?

Can you point to code where i can add more buffers? In SDK or/and gstreamer cases?
One sensor - one NvBuffer.

Please share which Jetpack release you are using. The source code of nvarguscamerasrc is public and you can check the source code to get more information.

JetPack 4.6.0

Jetpack 4.6 is r32.6.1 and please download source code package from the page:

L4T Driver Package (BSP) Sources

You wrote:

It is multithreading in low-level code for capturing frame data. In nvarguscamerasrc plugin, it allocates single NvBuffer. For further enhancement, you can create multiple NvBuffer for buffering frame data and acquireFrame() can be called immediately.

So where i can set more than one buffer in argus multisession or syncsensor example?

Not gst src.

And i asked you how many buffers uses gst pipeline for 2 sensors.
It is sync or async frame acqusition?
Please answer me.

In gstreamer, the two cameras are launched individually. The two cameras are not synchronized. Each camera is one nvarguscamerasrc so one NvBuffer is allocated/used.

The sample demonstrates software sync:


If your use-case is dual camera synchronization, you may base on the sample to develop your use-case. Hardware synchronization is not supported.

My cameras setup is HW synchronized.

We are speaking about frame acquire synchronisation argus code. Not frame timestamp/shot sync.

But why multisession used one nvbuffer? It is not async code.

It is sync code. I am waiting every sensor frameAcquire.

Here is problem description:

This code have acquire sensor by sensor. Not in parallel.
Why if capture sessions are separated?

size_t cameraId{};
#pragma omp parallel for schedule(static) num_threads(6) 
            for( cameraId = 0; cameraId < m_camerasNum; ++ cameraId )
                const auto result{ cameraId )->capture( cameraId ).get() ) };
                if( result == 0 )
                    REPORT_ERROR( "Capture failed!" );

                Argus::UniqueObj< EGLStream::Frame > frame{ cameraId )->acquireFrame() };
                EGLStream::IFrame * iFrame{ Argus::interface_cast< EGLStream::IFrame >( frame ) };
                if( not iFrame )
                    std::cout << "Failed to acquire frame! " << cameraId << std::endl;
                } else
                    //                std::cout << cameraId << " " << iFrame->getNumber() << " " << iFrame->getTime() << std::endl;
                    // record
                        EGLStream::IImageJPEG * iJPEG{ Argus::interface_cast< EGLStream::IImageJPEG >( iFrame->getImage() ) };
                        if( iJPEG )
                            const auto file{ m_recordPath + "/" + std::to_string( cameraId ) + "/" + std::to_string( m_framesCounter ) + ".jpg" };
                            if( iJPEG->writeJPEG( file.c_str() ) != Argus::STATUS_OK )
                                std::cout << "Failed to write JPEG: " << file << std::endl;

                        m_doCapture = false;

            } // pragma

This is sync code:


This is async code:

#pragma omp parallel for 
    for( i = 0; i < 3; ++ i )

Where hidden mister NvBuffer?
In capture session? In producer? In consumer? In eglstream? In provider?

Or may be i should run 6 instances of nvargus-daemon?

One NvBuffer for all or each sensor has own buffer?

In the code you shared, NvBuffer is not created. For creating NvBuffer, please call createNvBuffer(). You can create multiple NvBuffer and then call copyToNvBuffer() to re-use the buffers. Your use-case is advancing and default sample may not be enough. Additional customization shall be required.

If i will copy buffer from image it becomes multithreading?

All sessions will be process frames parallel?

auto *iNativeBuffer = Argus::interface_cast<EGLStream::NV::IImageNativeBuffer>(iFrame->getImage());


You may create individual capture thread for each camera, so that the cameras are run in multithreading.

What customization i need? Argus has closed sources, acquireFrame locks thread. Where i should fix acquireFrame code?

Ok, i will try.

But gst pipeline with 2 sensors runs in 2 parallel threadExecute? Isn’t it?

And it pocess frames not parallel.

If you run this command:

Sensor-id 0 is one thread and sensor-id 1 is the other thread. The two threads capture frames parallelly and individually.


And we goes to the beginning of this story.

I got only 8 fps for 6 sensors.

For gst case and for my cpp case.


Here is beginning: Write jpeg faster from 6 cameras