ContinuousCaptureOnlyProcessLatest.legacy.cpp

The ContinuousCaptureOnlyProcessLatest.legacy program is a legacy version of the ContinuousCaptureOnlyProcessLatest.cpp example.

Note

This is a legacy version of ContinuousCaptureOnlyProcessLatest.cpp only needed when working on a system with a non C++11 capable compiler (e.g. Visual Studio smaller than version 2013 or gcc smaller than version 4.8. However please note that Impact Acquire these days is built using gcc 5.5.0 thus using an older compiler for building applications will most likely not result in working binaries!). For a detailed description please have a look on the modern version of this example. Even though the used C++ code is slightly different the general idea of the example is the same!

Source code

//
// @description: Example applications for Impact Acquire
// @copyright: Copyright (C) 2005 - 2023 Balluff GmbH
// @authors: APIs and drivers development team at Balluff GmbH
// @initial date: 2005-03-15
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice (including the next paragraph) shall be included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,i
// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
 
#ifdef _MSC_VER // is Microsoft compiler?
#   if _MSC_VER < 1300  // is 'old' VC 6 compiler?
#       pragma warning( disable : 4786 ) // 'identifier was truncated to '255' characters in the debug information'
#   endif // #if _MSC_VER < 1300
#endif // #ifdef _MSC_VER
#include <windows.h>
#include <process.h>
#include <iostream>
#include <limits>
#include <apps/Common/exampleHelper.h>
#include <mvIMPACT_CPP/mvIMPACT_acquire.h>
#include <mvIMPACT_CPP/mvIMPACT_acquire_GenICam.h>
#include <mvDisplay/Include/mvIMPACT_acquire_display.h>
 
#undef min // otherwise we can't work with the 'numeric_limits' template here as Windows defines a macro 'min'
#undef max // otherwise we can't work with the 'numeric_limits' template here as Windows defines a macro 'max'
 
// comment this line to see the effect of queue underruns
#define DROP_OUTDATED_IMAGES
// uncomment this line to get more output into the console window
//#define VERBOSE_OUTPUT
 
using namespace mvIMPACT::acquire;
using namespace mvIMPACT::acquire::display;
using namespace std;
 
static bool s_boTerminated = false;
 
//-----------------------------------------------------------------------------
struct ThreadParameter
//-----------------------------------------------------------------------------
{
    Device*             pDev;
    ImageDisplayWindow  displayWindow;
    ThreadParameter( Device* p, const string& windowTitle ) : pDev( p ), displayWindow( windowTitle ) {}
};
 
//-----------------------------------------------------------------------------
class TimeStampProvider
//-----------------------------------------------------------------------------
{
private:
    unsigned long long timestampTickFrequency_;
    mutable PropertyI64* pTimestamp_;
    Method* pTimestampLatch_;
public:
    explicit TimeStampProvider( Device* pDev ) : timestampTickFrequency_( 1000000000 ), pTimestamp_( 0 ), pTimestampLatch_( 0 )
    {
        GenICam::DeviceControl dc( pDev );
        GenICam::TransportLayerControl tlc( pDev );
        if( dc.timestamp.isValid() )
        {
            pTimestamp_ = new PropertyI64( dc.timestamp.hObj() );
        }
        else if( dc.timestampLatchValue.isValid() )
        {
            pTimestamp_ = new PropertyI64( dc.timestampLatchValue.hObj() );
        }
        else if( tlc.gevTimestampValue.isValid() )
        {
            pTimestamp_ = new PropertyI64( tlc.gevTimestampValue.hObj() );
            if( tlc.gevTimestampTickFrequency.isValid() )
            {
                timestampTickFrequency_ = tlc.gevTimestampTickFrequency.read();
            }
        }
 
        if( dc.timestampLatch.isValid() )
        {
            pTimestampLatch_ = new Method( dc.timestampLatch.hObj() );
        }
        else if( tlc.gevTimestampControlLatch.isValid() )
        {
            pTimestampLatch_ = new Method( tlc.gevTimestampControlLatch.hObj() );
        }
 
        if( dc.timestampReset.isValid() )
        {
            dc.timestampReset.call();
        }
        else if( tlc.gevTimestampControlReset.isValid() )
        {
            tlc.gevTimestampControlReset.call();
        }
    }
    ~TimeStampProvider()
    {
        delete pTimestamp_;
        delete pTimestampLatch_;
    }
    unsigned long long getTimestamp_us( void ) const
    {
        if( pTimestamp_ && pTimestampLatch_ && ( static_cast<TDMR_ERROR>( pTimestampLatch_->call() ) == DMR_NO_ERROR ) )
        {
            const double t = static_cast<double>( pTimestamp_->read() ) / static_cast<double>( timestampTickFrequency_ );
            return static_cast<unsigned long long>( t * 1000000 );
        }
        return numeric_limits<unsigned long long>::max();
    }
};
 
//-----------------------------------------------------------------------------
unsigned int __stdcall liveThread( void* pData )
//-----------------------------------------------------------------------------
{
    ThreadParameter* pThreadParameter = reinterpret_cast<ThreadParameter*>( pData );
    cout << "Initialising the device. This might take some time..." << endl;
    try
    {
        pThreadParameter->pDev->open();
    }
    catch( const ImpactAcquireException& e )
    {
        // this e.g. might happen if the same device is already opened in another process...
        cout << "An error occurred while opening the device " << pThreadParameter->pDev->serial.read()
             << "(error code: " << e.getErrorCodeAsString() << ")." << endl
             << "Press [ENTER] to end the application..." << endl;
        cin.get();
        return 0;
    }
 
    ImageDisplay& display = pThreadParameter->displayWindow.GetImageDisplay();
    // establish access to the statistic properties
    Statistics statistics( pThreadParameter->pDev );
    // create an interface to the device found
    FunctionInterface fi( pThreadParameter->pDev );
 
    TimeStampProvider* pTimestampProvider = 0;
    if( pThreadParameter->pDev->interfaceLayout.read() == dilGenICam )
    {
        pTimestampProvider = new TimeStampProvider( pThreadParameter->pDev );
    }
 
    // Send all requests to the capture queue. There can be more than 1 queue for some devices, but for this sample
    // we will work with the default capture queue. If a device supports more than one capture or result
    // queue, this will be stated in the manual. If nothing is said about it, the device supports one
    // queue only. This loop will send all requests currently available to the driver. To modify the number of requests
    // use the property mvIMPACT::acquire::SystemSettings::requestCount at runtime (note that some devices will
    // only allow to modify this parameter while NOT streaming data!) like so
    //     SystemSettings ss( pThreadParameter->pDev );
    //     ss.requestCount.write( 10 );
    // or the property mvIMPACT::acquire::Device::defaultRequestCount BEFORE opening the device.
    // Please note that reducing the 'requestCount' at runtime is only possible when the driver is current not holding
    // ANY request and EVERY request returned to the application has already been unlocked again.
    TDMR_ERROR result = DMR_NO_ERROR;
    unsigned long long previousTimestamp = 0;
    while( ( result = static_cast<TDMR_ERROR>( fi.imageRequestSingle() ) ) == DMR_NO_ERROR ) {};
    if( pTimestampProvider )
    {
        previousTimestamp = pTimestampProvider->getTimestamp_us();
    }
    if( result != DEV_NO_FREE_REQUEST_AVAILABLE )
    {
        cout << "'FunctionInterface.imageRequestSingle' returned with an unexpected result: " << result
             << "(" << ImpactAcquireException::getErrorCodeAsString( result ) << ")" << endl;
    }
 
    manuallyStartAcquisitionIfNeeded( pThreadParameter->pDev, fi );
    // run thread loop
    int requestNr = INVALID_ID;
    Request* pRequest = 0;
    // we always have to keep at least 2 images as the displayWindow module might want to repaint the image, thus we
    // can not free request buffer unless we have assigned the displayWindow to a new buffer.
    Request* pPreviousRequest = 0;
    const unsigned int timeout_ms = 500;
    unsigned int cnt = 0;
    while( !s_boTerminated )
    {
        // Queue underruns can be simulated by switching of this section and maybe fine-tune the value of
        // the sleep time in the call to 'Sleep' below.
#ifdef DROP_OUTDATED_IMAGES
        // if results are queued because the image processing was to slow for the current framerate
        // get the newest valid image and throw away all others
        do
        {
            // get a queued result from the default capture queue without waiting(just check if there are pending results)
            requestNr = fi.imageRequestWaitFor( 0 );
            if( fi.isRequestNrValid( requestNr ) )
            {
                pRequest = fi.getRequest( requestNr );
                if( pRequest )
                {
#   ifdef VERBOSE_OUTPUT
                    cout << "Unlocking outdated request:            request_number=" << pRequest->getNumber() << "." << endl;
#   endif // #ifdef VERBOSE_OUTPUT
                    // discard an outdated buffer
                    pRequest->unlock();
                    // get timestamp to always have latest timestamp after dumping
                    if( pTimestampProvider )
                    {
                        previousTimestamp = pTimestampProvider->getTimestamp_us();
                    }
                    else
                    {
                        previousTimestamp = pPreviousRequest->infoTimeStamp_us.read();
                    }
                    // and send it to the driver again to request new data into it
                    fi.imageRequestSingle();
                }
                pRequest = 0;
            }
        }
        while( fi.isRequestNrValid( requestNr ) );
#endif // #ifdef DROP_OUTDATED_IMAGES
 
        if( !pRequest )
        {
            // there was no image in the queue we have to wait for results from the default capture queue
#ifdef VERBOSE_OUTPUT
            cout << "Waiting for a request to become ready:";
#endif // #ifdef VERBOSE_OUTPUT
            requestNr = fi.imageRequestWaitFor( timeout_ms );
            pRequest = fi.isRequestNrValid( requestNr ) ? fi.getRequest( requestNr ) : 0;
        }
#ifdef VERBOSE_OUTPUT
        else
        {
            cout << "Processing already received request:  ";
        }
        cout << " request_number=" << pRequest->getNumber() << " and timestamp=" << pRequest->infoTimeStamp_us.read() << " and last_timestamp=" << previousTimestamp << " and difference=" << ( signed int )( pRequest->infoTimeStamp_us.read() - previousTimestamp ) << "usec." << endl;
#endif // #ifdef VERBOSE_OUTPUT
 
        if( pRequest )
        {
            if( pRequest->isOK() )
            {
                ++cnt;
                // here we can display some statistical information every 100th image
                if( cnt % 100 == 0 )
                {
                    cout << "Info from " << pThreadParameter->pDev->serial.read()
                         << ": " << statistics.framesPerSecond.name() << ": " << statistics.framesPerSecond.readS()
                         << ", " << statistics.errorCount.name() << ": " << statistics.errorCount.readS()
                         << ", " << statistics.captureTime_s.name() << ": " << statistics.captureTime_s.readS() << endl;
                }
                display.SetImage( pRequest );
                display.Update();
 
                // simulates lengthy image processing time. Note that for devices or applications using a frame rate lower
                // than 5 fps this will have no effect. To simulate the desired behaviour of this example, this sleep time
                // needs to be longer than 1/frames per second!
                // Queue underruns will occur when e.g. the image processing time of your application (in this sample simulated
                // with \c sleep()) is longer than 1/frames per second as then new images will become ready faster than new
                // capture buffers will be sent to the driver. Applications might want to process the latest frame only then.
                // However it is crucial to understand that this still can only work, if the driver has enough requests
                // to stay busy during the image processing time. Then when picking up the latest frame and
                // re-queuing all the other buffer during that pickup operation the application will show the desired
                // behaviour. If not, queue underruns will continue to happen!
                // Note that mvBlueFOX3-* cameras might return outdated images under certain conditions even after image
                // dropping, as images are currently streamed out of the device only on user request, i.e. only if USB
                // buffers are provided from the host. This example can show this behaviour, if the sleep time is longer
                // than 1/frames per second, as this leads to the accumulation of "old" images in the framebuffer of the
                // mvBlueFOX3.
                Sleep( 200 );
            }
            else
            {
                cout << "Error: " << pRequest->requestResult.readS() << endl;
            }
            if( pPreviousRequest )
            {
                // this image has been displayed thus the buffer is no longer needed...
                pPreviousRequest->unlock();
            }
            pPreviousRequest = pRequest;
            // this line is crucial for this application only. Without it buffers
            // will not be picked up in the correct way!
            pRequest = 0;
            // get timestamp at request time
            if( pTimestampProvider )
            {
                previousTimestamp = pTimestampProvider->getTimestamp_us();
            }
            else
            {
                previousTimestamp = pPreviousRequest->infoTimeStamp_us.read();
            }
            // send a new image request into the capture queue
            fi.imageRequestSingle();
        }
        else
        {
            // If the error code is -2119(DEV_WAIT_FOR_REQUEST_FAILED), the documentation will provide
            // additional information under TDMR_ERROR in the interface reference
            cout << "imageRequestWaitFor failed (" << requestNr << ", " << ImpactAcquireException::getErrorCodeAsString( requestNr ) << ")"
                 << ", timeout value too small?" << endl;
        }
    }
    manuallyStopAcquisitionIfNeeded( pThreadParameter->pDev, fi );
 
    // stop the displayWindow from showing freed memory
    display.RemoveImage();
    // In this sample all the next lines are redundant as the device driver will be
    // closed now, but in a real world application a thread like this might be started
    // several times an then it becomes crucial to clean up correctly.
 
    // free the last potentially locked request
    if( pPreviousRequest )
    {
        pPreviousRequest->unlock();
    }
    // clear all queues
    fi.imageRequestReset( 0, 0 );
    delete pTimestampProvider;
    return 0;
}
 
//-----------------------------------------------------------------------------
int main( void )
//-----------------------------------------------------------------------------
{
    DeviceManager devMgr;
    Device* pDev = getDeviceFromUserInput( devMgr );
    if( !pDev )
    {
        cout << "Unable to continue! Press [ENTER] to end the application" << endl;
        cin.get();
        return 1;
    }
 
    // start the execution of the 'live' thread.
    cout << "Press [ENTER] to end the application" << endl;
    unsigned int dwThreadID;
    string windowTitle( "mvIMPACT_acquire sample, Device " + pDev->serial.read() );
    // initialise displayWindow window
    // IMPORTANT: It's NOT safe to create multiple displayWindow windows in multiple threads!!!
    ThreadParameter threadParam( pDev, windowTitle );
    HANDLE hThread = ( HANDLE )_beginthreadex( 0, 0, liveThread, ( LPVOID )( &threadParam ), 0, &dwThreadID );
    cin.get();
    s_boTerminated = true;
    WaitForSingleObject( hThread, INFINITE );
    CloseHandle( hThread );
    return 0;
}