Image Manager/Cvb++/CppMultiStream

This example program is located in your CVB installation under %CVB%Tutorial/Image Manager/Cvb++/CppMultiStream.

main.cpp:

// Demonstrates an image acquisition application that uses multiple streams to acquire from. Requires:
// A connected and configured GenICam device, or a mock device that is provided by CVMockTL. If you
// prefer to execute this tutorial with the mock device, please pass the "--mock" switch to the
// executable.
// ----------------------------------------------------------------------------
// ----------------------------------------------------------------------------
 
#include <iostream>
#include <chrono>
 
#include <cvb/device_factory.hpp>
#include <cvb/image.hpp>
#include <cvb/global.hpp>
 
// Constants:
static const constexpr auto TIMEOUT = std::chrono::milliseconds(3000);
static const constexpr int NUM_ELEMENTS_TO_ACQUIRE = 10;
 
static std::map<Cvb::WaitStatus, const char*> WAIT_ERROR_STATES{ {Cvb::WaitStatus::Timeout, "Timeout"},
                                                                 {Cvb::WaitStatus::Abort, "Abort"} };
 
int main(int argc, char* argv[])
{
  try
  {
    // Check if it is requested to run with a mock GenTL Producer.
    bool demonstrateWithMock =
      ((argc > 1) && (std::string(argv[1]).find("--mock") != std::string::npos)) ? true : false;
 
    // Configure the discovery flags.
    auto discoverFlags = Cvb::DiscoverFlags::IgnoreVins;  // Ignores all of the CVB VINs.
 
    // If it is requested to run with a mock, then additionally set an appropriate flag.
    if (demonstrateWithMock)
      discoverFlags |= Cvb::DiscoverFlags::IncludeMockTL;  // Include CVMockTL.
 
    // Retrieve a device.
    auto infoList = Cvb::DeviceFactory::Discover(discoverFlags);
 
    // Can't continue the demo if there's no device:
    if (infoList.empty())
      throw std::runtime_error("No devices found.");
 
    // Determine the target device.
    Cvb::String accessToken;
 
    if (demonstrateWithMock)
    {
      for (auto n = 0; (n < infoList.size()) && accessToken.empty(); ++n)
        if (infoList.at(n).AccessToken().find("MockTL") != std::string::npos)
          accessToken = infoList.at(n).AccessToken();
 
      // Make sure if CVMockTL is on the candidate list.
      if (accessToken.empty())
        throw std::runtime_error("Could not find CVMockTL.");
    }
    else
      accessToken = infoList.front().AccessToken();
 
    // Open the selected device.
    auto device =
      Cvb::DeviceFactory::Open<Cvb::GenICamDevice>(infoList.front().AccessToken(), Cvb::AcquisitionStack::GenTL);
 
    // Get all streams that belong to the device.
    std::vector<Cvb::ImageStreamPtr> streams;
    std::generate_n(std::back_inserter(streams), device->StreamCount(),
      [&device, i = 0]() mutable { return device->Stream<Cvb::ImageStream>(i++); });
    std::cout << "Stream count: " << streams.size() << "\n";
 
    // Let all streams start data streaming.
    for (const auto stream : streams)
      stream->Start();
 
    // Acquire data.
    // Note: Getting the data is sequential here for simplicity;
    //       concurrent wait on different streams is the more likely use case.
    for (auto imageIndex = 0; imageIndex < NUM_ELEMENTS_TO_ACQUIRE; ++imageIndex)
    {
      for (auto streamIndex = 0u; streamIndex < streams.size(); ++streamIndex)
      {
        const auto stream = streams[streamIndex];
        auto [image, waitStatus, nodeMaps] = stream->WaitFor(TIMEOUT);
 
        switch (waitStatus)
        {
        default:
          std::cout << "Unknown wait status.\n";
        case Cvb::WaitStatus::Abort:
        case Cvb::WaitStatus::Timeout:
        {
          std::cout << "Wait status not OK: " << WAIT_ERROR_STATES[waitStatus] << "\n";
          continue;
        }
        case Cvb::WaitStatus::Ok:
          break;
        }
 
        std::cout << "Stream #" << streamIndex << ", Image #" << imageIndex;
        std::cout << std::hex << ", Width: " << image->Width() <<
          ", Height: " << image->Height() << "\n";
      }
    }
 
    // Terminate the streaming.
    for (const auto stream : streams)
      stream->TryAbort();
  }
  catch (const std::exception& error)
  {
    std::cout << error.what() << std::endl;
  }
  return 0;
}