ImageEvents¶
ImageEvents.cpp shows how to acquire images using the image event handler. It relies on information provided in the Enumeration, Acquisition, and NodeMapInfo examples.
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/**
* @example ImageEvents.cpp
*
* @brief ImageEvents.cpp shows how to acquire images using the image event
* handler. It relies on information provided in the Enumeration, Acquisition,
* and NodeMapInfo examples.
*
* It can also be helpful to familiarize yourself with the NodeMapCallback
* example, as nodemap callbacks follow the same general procedure as
* events, but with a few less steps.
*
* This example creates a user-defined class, ImageEventHandlerImpl, that inherits
* from the Spinnaker class, ImageEventHandler. ImageEventHandlerImpl allows the user to
* define any properties, parameters, and the event itself while ImageEventHandler
* allows the child class to appropriately interface with Spinnaker.
*
* Please leave us feedback at: https://www.surveymonkey.com/r/TDYMVAPI
* More source code examples at: https://github.com/Teledyne-MV/Spinnaker-Examples
* Need help? Check out our forum at: https://teledynevisionsolutions.zendesk.com/hc/en-us/community/topics
*/
#include "Spinnaker.h"
#include "SpinGenApi/SpinnakerGenApi.h"
#include <iostream>
#include <sstream>
using namespace Spinnaker;
using namespace Spinnaker::GenApi;
using namespace Spinnaker::GenICam;
using namespace std;
// This helper function allows the example to sleep in both Windows and Linux
// systems. Note that Windows sleep takes milliseconds as a parameter while
// Linux systems take microseconds as a parameter.
void SleepyWrapper(int milliseconds)
{
#if defined WIN32 || defined _WIN32 || defined WIN64 || defined _WIN64
Sleep(milliseconds);
#else
usleep(1000 * milliseconds);
#endif
}
// This class defines the properties, parameters, and the event handler itself. Take a
// moment to notice what parts of the class are mandatory, and what have been
// added for demonstration purposes. First, any class used to define image event handlers
// must inherit from ImageEventHandler. Second, the method signature of OnImageEvent()
// must also be consistent. Everything else - including the constructor,
// deconstructor, properties, body of OnImageEvent(), and other functions -
// is particular to the example.
class ImageEventHandlerImpl : public ImageEventHandler
{
public:
// The constructor retrieves the serial number and initializes the image
// counter to 0.
ImageEventHandlerImpl(CameraPtr pCam)
{
// Retrieve device serial number
INodeMap& nodeMap = pCam->GetTLDeviceNodeMap();
m_deviceSerialNumber = "";
CStringPtr ptrDeviceSerialNumber = nodeMap.GetNode("DeviceSerialNumber");
if (IsReadable(ptrDeviceSerialNumber))
{
m_deviceSerialNumber = ptrDeviceSerialNumber->GetValue();
}
// Initialize image counter to 0
m_imageCnt = 0;
// Release reference to camera
pCam = nullptr;
//
// Set default image processor color processing method
//
// *** NOTES ***
// By default, if no specific color processing algorithm is set, the image
// processor will default to NEAREST_NEIGHBOR method.
//
m_processor.SetColorProcessing(SPINNAKER_COLOR_PROCESSING_ALGORITHM_HQ_LINEAR);
}
~ImageEventHandlerImpl()
{
}
// This method defines an image event. In it, the image that triggered the
// event is converted and saved before incrementing the count. Please see
// Acquisition_CSharp example for more in-depth comments on the acquisition
// of images.
void OnImageEvent(ImagePtr image)
{
// Save a maximum of 10 images
if (m_imageCnt < mk_numImages)
{
cout << "Image event occurred..." << endl;
// Check image retrieval status
if (image->IsIncomplete())
{
cout << "Image incomplete with image status " << image->GetImageStatus() << "..." << endl << endl;
}
else
{
// Print image information
cout << "Grabbed image " << m_imageCnt << ", width = " << image->GetWidth()
<< ", height = " << image->GetHeight() << endl;
// Convert image to mono 8
ImagePtr convertedImage = m_processor.Convert(image, PixelFormat_Mono8);
// Create a unique filename and save image
ostringstream filename;
filename << "ImageEvents-";
if (m_deviceSerialNumber != "")
{
filename << m_deviceSerialNumber.c_str() << "-";
}
filename << m_imageCnt << ".jpg";
convertedImage->Save(filename.str().c_str());
cout << "Image saved at " << filename.str() << endl << endl;
// Increment image counter
m_imageCnt++;
}
}
}
// Getter for image counter
int getImageCount()
{
return m_imageCnt;
}
// Getter for maximum images
int getMaxImages()
{
return mk_numImages;
}
private:
static const unsigned int mk_numImages = 10;
unsigned int m_imageCnt;
string m_deviceSerialNumber;
ImageProcessor m_processor;
};
// This function configures the example to execute image events by preparing and
// registering an image event.
int ConfigureImageEvents(CameraPtr pCam, ImageEventHandlerImpl*& imageEventHandler)
{
int result = 0;
try
{
//
// Create image event handler
//
// *** NOTES ***
// The class has been constructed to accept a camera pointer in order
// to allow the saving of images with the device serial number.
//
imageEventHandler = new ImageEventHandlerImpl(pCam);
//
// Register image event handler
//
// *** NOTES ***
// Image event handlers are registered to cameras. If there are multiple
// cameras, each camera must have the image event handlers registered to it
// separately. Also, multiple image event handlers may be registered to a
// single camera.
//
// *** LATER ***
// Image event handlers must be unregistered manually. This must be done prior
// to releasing the system and while the image event handlers are still in
// scope.
//
pCam->RegisterEventHandler(*imageEventHandler);
}
catch (Spinnaker::Exception& e)
{
cout << "Error: " << e.what() << endl;
result = -1;
}
return result;
}
// This function waits for the appropriate amount of images. Notice that
// whereas most examples actively retrieve images, the acquisition of images is
// handled passively in this example.
int WaitForImages(ImageEventHandlerImpl*& imageEventHandler)
{
int result = 0;
try
{
//
// Wait for images
//
// *** NOTES ***
// In order to passively capture images using image events and
// automatic polling, the main thread sleeps in increments of 200 ms
// until 10 images have been acquired and saved.
//
const int sleepDuration = 200; // in milliseconds
while (imageEventHandler->getImageCount() < imageEventHandler->getMaxImages())
{
cout << "\t//" << endl;
cout << "\t// Sleeping for " << sleepDuration << " ms. Grabbing images..." << endl;
cout << "\t//" << endl;
SleepyWrapper(sleepDuration);
}
}
catch (Spinnaker::Exception& e)
{
cout << "Error: " << e.what() << endl;
result = -1;
}
return result;
}
// This functions resets the example by unregistering the image event handler.
int ResetImageEvents(CameraPtr pCam, ImageEventHandlerImpl*& imageEventHandler)
{
int result = 0;
try
{
//
// Unregister image event handler
//
// *** NOTES ***
// It is important to unregister all image event handlers from all cameras
// they are registered to.
//
pCam->UnregisterEventHandler(*imageEventHandler);
// Delete image event handler (because it is a pointer)
delete imageEventHandler;
cout << "Image events unregistered..." << endl << endl;
}
catch (Spinnaker::Exception& e)
{
cout << "Error: " << e.what() << endl;
result = -1;
}
return result;
}
// This function prints the device information of the camera from the transport
// layer; please see NodeMapInfo example for more in-depth comments on printing
// device information from the nodemap.
int PrintDeviceInfo(INodeMap& nodeMap)
{
int result = 0;
cout << endl << "*** DEVICE INFORMATION ***" << endl << endl;
try
{
FeatureList_t features;
CCategoryPtr category = nodeMap.GetNode("DeviceInformation");
if (IsReadable(category))
{
category->GetFeatures(features);
FeatureList_t::const_iterator it;
for (it = features.begin(); it != features.end(); ++it)
{
try
{
CNodePtr pfeatureNode = *it;
cout << pfeatureNode->GetName() << " : ";
CValuePtr pValue = (CValuePtr)pfeatureNode;
cout << (IsReadable(pValue) ? pValue->ToString() : gcstring("Node not readable"));
cout << endl;
}
catch (Spinnaker::Exception)
{
cout << "Node not readable" << endl;
}
}
}
else
{
cout << "Device control information not readable." << endl;
}
}
catch (Spinnaker::Exception& e)
{
cout << "Error: " << e.what() << endl;
result = -1;
}
return result;
}
// This function passively waits for images by calling WaitForImages(). Notice that
// this function is much shorter than the AcquireImages() function of other examples.
// This is because most of the code has been moved to the image event's OnImageEvent()
// method.
int AcquireImages(
CameraPtr pCam,
INodeMap& nodeMap,
INodeMap& nodeMapTLDevice,
ImageEventHandlerImpl*& imageEventHandler)
{
int result = 0;
cout << endl << endl << "*** IMAGE ACQUISITION ***" << endl << endl;
try
{
// Set acquisition mode to continuous
CEnumerationPtr ptrAcquisitionMode = nodeMap.GetNode("AcquisitionMode");
if (!IsReadable(ptrAcquisitionMode) || !IsWritable(ptrAcquisitionMode))
{
cout << "Unable to get or set acquisition mode to continuous (node retrieval). Aborting..." << endl << endl;
return -1;
}
CEnumEntryPtr ptrAcquisitionModeContinuous = ptrAcquisitionMode->GetEntryByName("Continuous");
if (!IsReadable(ptrAcquisitionModeContinuous))
{
cout << "Unable to get acquisition mode to continuous (enum entry retrieval). Aborting..." << endl << endl;
return -1;
}
int64_t acquisitionModeContinuous = ptrAcquisitionModeContinuous->GetValue();
ptrAcquisitionMode->SetIntValue(acquisitionModeContinuous);
cout << "Acquisition mode set to continuous..." << endl;
// Begin acquiring images
pCam->BeginAcquisition();
cout << "Acquiring images..." << endl;
// Retrieve images using image event handler
WaitForImages(imageEventHandler);
// End acquisition
pCam->EndAcquisition();
}
catch (Spinnaker::Exception& e)
{
cout << "Error: " << e.what() << endl;
result = -1;
}
return result;
}
// This function acts as the body of the example; please see NodeMapInfo example
// for more in-depth comments on setting up cameras.
int RunSingleCamera(CameraPtr pCam)
{
int result = 0;
int err = 0;
try
{
// Retrieve TL device nodemap and print device information
INodeMap& nodeMapTLDevice = pCam->GetTLDeviceNodeMap();
result = PrintDeviceInfo(nodeMapTLDevice);
// Initialize camera
pCam->Init();
// Retrieve GenICam nodemap
INodeMap& nodeMap = pCam->GetNodeMap();
// Configure image events
ImageEventHandlerImpl* imageEventHandler;
err = ConfigureImageEvents(pCam, imageEventHandler);
if (err < 0)
{
return err;
}
// Acquire images using the image event handler
result = result | AcquireImages(pCam, nodeMap, nodeMapTLDevice, imageEventHandler);
// Reset image events
result = result | ResetImageEvents(pCam, imageEventHandler);
// Deinitialize camera
pCam->DeInit();
}
catch (Spinnaker::Exception& e)
{
cout << "Error: " << e.what() << endl;
result = -1;
}
return result;
}
// Example entry point; please see Enumeration example for additional
// comments on the steps in this function.
int main(int /*argc*/, char** /*argv*/)
{
// Since this application saves images in the current folder
// we must ensure that we have permission to write to this folder.
// If we do not have permission, fail right away.
FILE* tempFile = fopen("test.txt", "w+");
if (tempFile == nullptr)
{
cout << "Failed to create file in current folder. Please check "
"permissions."
<< endl;
cout << "Press Enter to exit..." << endl;
getchar();
return -1;
}
fclose(tempFile);
remove("test.txt");
int result = 0;
// Print application build information
cout << "Application build date: " << __DATE__ << " " << __TIME__ << endl << endl;
// Retrieve singleton reference to system object
SystemPtr system = System::GetInstance();
// Print out current library version
const LibraryVersion spinnakerLibraryVersion = system->GetLibraryVersion();
cout << "Spinnaker library version: " << spinnakerLibraryVersion.major << "." << spinnakerLibraryVersion.minor
<< "." << spinnakerLibraryVersion.type << "." << spinnakerLibraryVersion.build << endl
<< endl;
// Retrieve list of cameras from the system
CameraList camList = system->GetCameras();
unsigned int numCameras = camList.GetSize();
cout << "Number of cameras detected: " << numCameras << endl << endl;
// Finish if there are no cameras
if (numCameras == 0)
{
// Clear camera list before releasing system
camList.Clear();
// Release system
system->ReleaseInstance();
cout << "Not enough cameras!" << endl;
cout << "Done! Press Enter to exit..." << endl;
getchar();
return -1;
}
// Run example on each camera
for (unsigned int i = 0; i < numCameras; i++)
{
cout << endl << "Running example for camera " << i << "..." << endl;
result = result | RunSingleCamera(camList.GetByIndex(i));
cout << "Camera " << i << " example complete..." << endl << endl;
}
// Clear camera list before releasing system
camList.Clear();
// Release system
system->ReleaseInstance();
cout << endl << "Done! Press Enter to exit..." << endl;
getchar();
return result;
}